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					    ORAL
PRESENTATION
 ABSTRACTS
PALYNOLOGICAL IDENTIFICATION OF SYSTEMS TRACTS IN
JURASSIC PARALIC DEPOSITS IN THE NORTH SEA BASIN

O.A. ABBINK
TNO-NITG, P.O. Box 80015, 3508 TA Utrecht, NL

Paralic depositional sequences in the Jurassic of the North Sea form an important economic
objective. In these sequences, palynomorphs are the most abundant (micro) fossil group and
palynology is increasingly challenged to identify systems tracts and parasequences.
         Based on the general ecologies of aquatic palynomorphs and on a recently developed
Sporomorph EcoGroup model it can be demonstrated that (1) the interplay of the distribution
patterns of brackish-marine, freshwater and terrestrial palynomorphs, and (2) distribution
patterns of even solely terrestrial palynomorphs (grouped in six Sporomorph EcoGroups
(SEGs), viz. Upland, Lowland, River, Pioneer, Coastal, and Tidally-influenced SEG), can be
used for the recognition of sea-level fluctuations in paralic settings.
         The sea-level changes recognized based on the SEG model allow the identification of
discrete palynological sea-level induced units (Sea-level Induced Palynomorph Succession;
SIPS). Within the SIPS (see Figure, four phases can be distinguished: (1) a ―wet‖ Lowland
SEG phase, (2) a phase with maximum abundance of Upland, Coastal and/or Tidally-
influenced SEGs and a high marine/terrestrial ratio, (3) a Coastal SEG phase, and (4) a ―dry‖
Lowland SEG phase. Based on the correlation of water-balance and drainage conditions with
sea-level, the four phases are considered to correlate to the (1) late LST and TST, (2) MFS,
(3) early HST, and (4) late HST, respectively. The boundary of between SIPSs reflects the
abrupt shift from a regressional to a transgressional regime and is considered to
approximately correlate to the SB in a paralic setting.



                                                                                       SB

                                                                lHST
                                                                                    lHST

                                                                eHST    eHST

                                                                             MFS
                                                                 MFS




                                                                 TST
                                                                                    TST


                                                              TST/LST
                                                                                           TS
                                                                         SIPS
                                                                         boundary

                                                                 LST                       LST
                                                                              SB

                                                                lHST          lHST
                                                                                                 T
CORRELATION OF MARINE CRETACEOUS
BIOSTRATIGRAPHIC EVENTS ON AN AUSTRALIAN MARGIN

J. BACKHOUSE, R.J. CAMPBELL, M. DIXON, D.W. HAIG
School of Earth and Geographical Sciences, University of Western Australia, Crawley WA
6009, Australia
R.W. HOWE
Energy and Geoscience Institute, The University of Utah, 423 Wakara Way, Suite 300, Salt
Lake City UT 84112, USA
A.J. MORAY
Geological Survey of Western Australia, 100 Plain St, East Perth, WA 6004, Australia
B.A. TAYLOR
School of Earth and Geographical Sciences, University of Western Australia, Crawley WA
6009, Australia

Initial findings of a major project on the Australian Cretaceous are presented. The project
integrates palynostratigraphy, foraminiferal and nannofossil biostratigraphy, petrophysical logs
and sedimentology to document and correlate events that can be recognized on the Southern
Carnarvon Platform of Western Australia. This region is the classic area for study of the
Australian Cretaceous, and part of every stage from the Barremian to Maastrichtian is
represented. It is a tectonically stable area lying south of the North West Shelf, and during the
Cretaceous was a stable, low-gradient continental shelf that formed during mid-Valanginian
continental breakup.
A programme of continuous coring and sampling, at one metre or less intervals, has provided
material from all parts of the subsurface succession. All available surface sections have been
sampled. Shallow burial has resulted in excellent microfossil preservation, in contrast to that in
the Cretaceous of the North West Shelf (more deeply buried) and the Papuan Basin
(tectonically deformed).
The Cretaceous on the platform represents a succession of late transgressive and early
highstand depositional phases. Initial results show four progressively deepening siliciclastic
depositional cycles, Barremian to early Aptian (with inner neritic maximum flooding), late
Aptian (mid neritic), Albian (mid to outer neritic) and early to mid Cenomanian (shallow outer
neritic). Similar Aptian to Albian sequences are recognized in the vast interior basins of
Australia. The Turonian to Maastrichtian interval is a carbonate succession with five main
depositional cycles representing the early to mid Turonian, late Coniacian to Santonian, late
Campanian and late Maastrichtian, with maximum outermost neritic water depths during the
Turonian and the Santonian to early Campanian. Hiatuses separate the major sequences but
many minor hiatuses are present. The identification of tightly controlled species datum levels
within this succession will enable a standard Cretaceous chronostratigraphy and chronometry
for northern and western Australia. Despite several intervals of non-deposition, long
continuous sections provide accurate range data for critical index species, and enable
comparison of ranges between many cosmopolitan dinocysts, planktonic and benthic
foraminifera, and calcareous nannofossils.
THE BIOSTRATIGRAPHY OF THE EARLY EOCENE EL GARIA
FORMATION, HASDRUBAL FIELD, OFFSHORE TUNISIA

H.W. BAILEY, L.T. GALLAGHER, M.J. HAMPTON
Network Stratigraphic Consulting Ltd, Unit 60 The Enterprise Centre, Cranborne Road, Potters
Bar, Hertfordshire EN6 3DQ, UK
A. RACEY
BG Group, 100 Thames Valley Park Drive, Reading, Berkshire RG6 1PT, UK

The Hasdrubal Field is located in the Gulf of Gabes, offshore Tunisia, on a NNW -SSE
trending, fault bounded horst. The main reservoir facies comprises shallow marine, nummulitic
limestones of the El Garia Formation pinching-out into the age equivalent Bou Dabbous
Formation limestone to the north. The limestone reservoir unit is unconformably overlain by
Middle Eocene claystones and limestone of the Cherahil Formation which provide the seal to
this carbonate hydrocarbon trap.
         Detailed thin section examination of the microfaunal contents, excluding the dominant
Nummulites, from cored sections of four wells has yielded significant umbers of planktic and
smaller benthic foraminiferids, concentrated along well defined stratigraphic horizons. Detailed
stratigraphic and palaeoenvironmental information has also been obtained from ostracods and
molluscan debris also logged in thin section. The planktic foraminiferids rich levels are
recognised as maximum flooding events which can be correlated across the field allowing the
definition of discrete reservoir units or compartments. They can also be tentatively calibrated
with second and third order sequence cycles.
         A parallel study of the calcareous nannoplankton has been carried out on selected
samples from the El Garia reservoir section and from the Chouabine and Cherahil formations,
which immediately under- and overlie the reservoir carbonates. Detailed microfaunal and
nannoplankton analyses of the age equivalent Bou Dabbous Formation limestone from the
Malkadir-1 well have also been completed in order to provide a section from a more ‗offshore‘
plankton-rich, location against which the shallow marine El Garia reservoir carbonates and
sporadic flooding events can be calibrated.
ERIC O. CALLEN AND THE EARLY YEARS OF COPROLITE
ANALYSIS (1900-1970)

V.M. BRYANT, Jr
Department of Anthropology (TAMU-4252), Texas A&M University, College Station, Texas
77843-4352, USA
G.W. DEAN
Office of Cultural Affairs (Rm 320), 228 E. Palace Ave., Santa Fe, NM 87501, USA

The detailed analysis of human coprolites, as a recognized field of science, is barely 40 years
old. Dr. Eric O. Callen, the founder and developer of the discipline, has been dead for more
than 30 years yet the techniques and ideas he developed and perfected continue to guide the
discipline today; a discipline that has refined analyses in areas than he would ever have
dreamed possible. Callen ushered in the modern age of human coprolite analysis during the
late 1950s and early 1960s. He worked alone and with missionary zeal to convince
archaeologists, botanists, zooarchaeologists, and anyone else who would listen of the
importance of prehistoric human fecal research. From the beginning many fellow scientists
considered his research to be unimportant and frivolous yet Callen never wavered from his
commitment until his untimely death in Peru in 1970.
          Eric Callen was an unlikely person to become the "father" of coprolite analysis. He
had no anthropology or archaeology background. After receiving a doctorate in botany from
the University of Edinburgh in Scotland he spent his entire career as a professor of plant
pathology at McGill University in Canada. His first exposure to the study of coprolites came by
accident when an archaeologist gave him some prehistoric human feces that had been found
during the excavation of an early agricultural site in the coastal region of Peru. Callen‘s initial
interest in the fecal remains consisted only of a search for fungal spores of potential plant
pathogens that might have infected prehistoric Peruvian maize, and in turn been harvested
and eaten with maize by humans. That initial study led Callen into a new dimension of
research, which was to become the basis for all future coprolite studies. Callen‘s initial diet
reconstructions were based on a wide variety of plant and animal macro evidence that he
discovered during his first analysis. Although not a palynologists, he was quick to realize the
potential value of pollen studies and worked with others to examine the pollen from his fecal
studies. His new coprolite research interest was far removed from the academic courses he
taught, the plant pathology research he conducted, and it earned him little praise or respect
from his colleagues most of whom believed he was wasting valuable research time.
          During the short period of his remaining life he developed the standards now used for
coprolite processing, identification, and analyses. However, for years no other scientist
followed in Callen‘s path. Callen never taught a course on the subject, never received an
award or praise for his pioneering efforts, and had only one graduate student who was ever
interested in fecal research. During his brief decade of coprolite research Callen‘s only
research space was a tiny 6 x 8 foot room and he was frequently the victim of jokes and
reticule by his colleagues.
          Today, Callen would be gladdened to learn that after his death others built upon his
initial research efforts and extended fecal studies to include the analysis of plant macrofossils,
pollen, phytoliths, amino acids, trace elements, pollen concentration values, gas
chromatographic data, faunal and insect studies, and most recently the extraction and
identification of DNA from human feces using PCR techniques.
THE RAVENSCAR GROUP: A GEOLOGICAL ANALOGUE FOR
THE MIDDLE JURASSIC RESERVOIRS OF THE NORTH SEA
AND MID NORWAY

N. BUTLER
Robertson Research Int. Ltd., Llanrhos, Llandudno Ll30 1SA, UK
M.A. CHARNOCK
Norsk Hydro AS, Research Centre, N-5020, Bergen
K.O. HAGER
Norsk Hydro AS, Luanda, Angola
C.A. WATKINS
Robertson Research Int. Ltd., Llanrhos, Llandudno Ll30 1SA, UK

Despite their maturity, Middle Jurassic sandstones of the North Sea and Mid Norway still
represent some of the most prolific hydrocarbon reservoirs in Northwest Europe. Of these,
the Brent and Fangst Groups are particularly important and despite the vast number of
penetrative wells, the published chronostratigraphic schemes are poorly calibrated with well-
dated, onshore sections.
          The current scheme features improvements in stratigraphic resolution, which are
largely the result of an integrated biostratigraphic and sedimentological study of the Middle
Jurassic Ravenscar Group, Cleveland Basin, England. A field excursion involving Robertson
and Norsk Hydro geologists was undertaken to investigate relevant sections on the Yorkshire
coast. A detailed composite log was produced for the Dogger, Saltwick, Eller Beck, Cloughton
and Scarborough Formations where sedimentary facies are comparable to those seen in
Brent and Fangst Group cores. Additionally, lateral facies relationships and typical facies
sequences were documented. These localities were simultaneously sampled for high-
resolution biostratigraphy and in excess 100 samples were analysed for palynology and
micropalaeontology. The resultant dataset has been integrated with the sedimentological
facies to place the quantitative biostratigraphic data within a detailed depositional framework.
As a result of this integration the following observations have been made:
         1. The shelfal marine, condensed Dogger Formation is of ‗earliest‘ Aalenian age and
correlative with Broom and Ile Formations.
         2. The Aalenian Saltwick Formation (non-marine/brackish coastal plain/deltaic
sediments) and Eller Beck Formation (marine incursion) correlate with Rannoch-Etive-Ness
and the Not-‗lower‘ Garn genetic packages.
         3. The variably non-marine to shelfal sediments of the Cloughton Formation is either
unrepresented or may be only partly represented in the Brent Province and Mid Norway due to
a regional unconformity which truncates early Bajocian sediments.
          4. The Scarborough Formation is a retrogradational package, which was deposited in
a shelfal environment and is of ‗latest‘ early to ‗earliest‘ late Bajocian age. The formation is
correlative with the older part of the Tarbert-Heather and the ‗upper‘ Garn-Melke genetic
packages.
          Studying robustly dated outcrop analogues which lack major stratigraphic breaks like
the Ravenscar Group can provide data which may be used to improve reservoir modelling on
both regional and field-wide scales and consequently contribute to hydrocarbon exploration
and production strategies.
PALEOGENE PALYNOSTRATIGRAPHY OF THE PALEOLAKE
(TEPEXI COATZINGO) AT THE PUEBLA STATE, MEXICO

C. CARRANZA-SIERRA, E. MARTÍNEZ-HERNÁNDEZ
Instituto de Geología, Dpto. Paleontología. Lab. Palinología, Ciudad Universitaria, Coyoacán,
04510 D. F., México

The Balsas group was proposed by Fries in 1960, formed by variety of lithological units such
as conglomerates, siltstones, tuffs, gysums and lacustrine limestones. The Balsas group filled
the hydrological basin Mezcala-Balsas River in southern Mexico.
         Previously there are reports of the easterly part of this paleolake. In accordingly with
the results obtained by Martinez & Ramirez 1999, it was propose to launched a large survey
toward the west of the basin was a large lake extending several kilometers to the west. The
new localities studied proof the hypothesis that the Tepexi- Coatzingo was a large lake
extending several kilometers to the west.
         The new localities studies are listed as:
         ―Loc. Pie de Vaca‖ Tepexi de Rodriguez. That is a lithological sequence of 53 meters,
formed by siltstones and lacustrine limestones. Its age was erroneously established as
Pliocene Pleistocene base on footprints and a flamingo cast. In this locality a new closely
spaced sampling was undertaking near the flamingo. In these limestones several fungospores
are presence as Pluricellaesporites van der Hammen 1954, cf. P. beaufortensis Parson &
Norris 1999 reported for Paleocene of Texas USA; Hypoxilonites Elsik 1990a; cf.
Brachyporisporites atratus Kalgutkar 1993. The pollen grains are few. This assemblage
confirms the Paleogene age of this locality.
         Loc. ―El Tronco‖ Near Cuayuca
         The assemblage yields pollen Liliacidites, aff. Loeselia mexicana, Alnuspollenites,
Momipites, fresh water algae; Cymatiosphaera, Leiospheridia, Ovoidites grandis,
Zygnemataceae, Mycrocystis. Fungi spores: Diplodites, Papulusporonites.
         Loc ―Techcalli Blanco‖ Mimiapan
         This section of 50 meters constituted by siltstones and sandstones is characterized of
Pinuspollenites, Alnuspollenites, aff. Convolvulaceae, aff. Operculina codonatha,
Chenopodipollis, Quercoidites, aff. Gunnera, Myrtaceae, Potamogetonaceae, fresh water
algae; Cymatiosphaera. Fungi spores: Diplodites, Pluricellaesporites, Papulusporonites,
Fusiformisporites,      Hypoxylonites,       Dicellaesporites,    Dictiosporites,   Multicellites,
inapertisporites.
         Palaeoenvironmentally, these localities represent an ancient lake where abundant
fresh water sapropel with fragments of fresh water algae, fungal spores, were deposited.
These facies can be correlated with other units previously studied in the Coatzingo-Tepexi
basin. These finding confirm the existence of the great Coatzingo-Tepexi paleolake, probably,
situated near the sea level.
BIOSTRATIGRAPHICAL POTENTIAL OF THE CENOMANIAN
PORCELLANEOUS LARGER FORAMINIFERA

E. CAUS
Dpt. Geologia. Universitat Autònoma de Barcelona. 08193-Bellaterra, Spain
A. CALONGE
Dpt. Geología. Universidad de Alcalá de Henares, Spain
M. AGUILAR
Instituto Mexicano del Petróleo. Eje Central Lázaro Cárdenas, 150. México D.F., México

In Cenomanian shallow-water platform sediments, where planktic organisms are absent,
larger foraminifera, and particularly the porcellaneous ones, can be extremely useful for high-
resolution biostratigraphy. Other groups of larger foraminifera, such as orbitolinids or some
lamellar-perforate genera, have biostratigraphic value but they are restricted to some intervals
of time or some particular environments.
          However, the detailed stratigraphical distribution of porcellaneous larger foraminifera
in Cenomanian rocks is poorly known. This is mainly due to: 1) many Cenomanian shallow
water sedimentary rocks are hard limestones where larger foraminifera have to be identified in
thin section by means of a structural analysis in three dimensions, and the lack of such
analysis is responsible in the literature of many erroneous identifications; 2) many genera
and/or species were described many years ago, and the age of the type-localities is not given
or it is imprecise; 3) it doesn‘t exist a direct correlation between the occurrence of
porcellaneous larger foraminifera and the zones of plantkic organisms; 4) assemblages of
porcellaneous larger foraminifera differ significantly from one geographic area to another. For
instance, the diversified assemblage of alveolinids in the old world has never been recognised
in the Caribbean area, or within the Eurasian continent the genus Multispira is endemic to the
Near East.
          The aim of this work is to show the potential of porcellaneous larger foraminifera in
Cenomanian biostratigraphy. The study is centred in the Iberian Range and the Pyrenees
(north-eastern Spain), where previous regional studies and the good quality of the outcrops
facilitate detailed correlations between basinal and platform facies, and therefore to evaluate
the superposed assemblages of larger foraminifera including praealveolinids and its
associated fauna from the base of the Cenomanian to the extinction of the praealveolinids at
the end of this stage.
STRATIGRAPHIC CALIBRATION OF LATE CRETACEOUS
SEQUENCES, OFFSHORE MID NORWAY AREA.

M. A. CHARNOCK
Norsk Hydro Research Centre, N-5020 Bergen, Norway
S. CRITTENDEN
SC Independent Geological Consultant, Chagford Devon, United Kingdom

         The deeper water areas of the Vøring Basin, offshore Mid- Norway area, represent
one of the last major frontier areas for hydrocarbon exploration in the Norwegian Sector. To
date, single wells have been drilled on some of the larger structures e.g. Helland-Hansen
Arch, Gjallar Ridge and Vema Dome targeting thick sequences of Upper Cretaceous, deep
marine clastics. With the exceptions of the giant Ormen Lange gas field on the Møre margin
and the Nyk High (gas discovery), hydrocarbon success rate has been low and disappointing
but this is considered to be mainly related to understanding the hydrocarbon source and
migration history rather than the lack of significant reservoirs. The challenge has been to
integrate the biostratigraphy, well logs and seismic information to produce a regionally
applicable, sequence stratigraphic framework to link these structures and improve our
understanding of the geological evolution of the area.
         This study presents the sequence stratigraphy and biostratigraphic characterisation of
the Upper Cretaceous interval and the interpretation is based on an extensive biostratigraphic
review of wells from Quadrants 6305 to 6707. The surfaces have been defined, in practical
terms, by a series of 'key' microfossil events based on a combination of palynology (marine
microplankton) and micropalaeontology (planktonic and benthonic foraminifera, radiolaria and
diatoms) to correlate surfaces designated as representing either sequence boundaries (SB),
transgressive surfaces (TS) or surfaces of maximum marine transgression (MTS) for
integration with wireline logs and seismic stratigraphy. A series of type sections are
designated using or relating these, wherever possible to the wells designated by Dalland et al.
(1988) in their development of a lithostratigraphic scheme for the better understood Halten
Terrace area of the eastern basin margin and the biostratigraphic zonation is calibrated to the
standard chronostratigraphic framework established for European Basins by Hardenbol et al.
(1998). It is possible to relate most of the microfossils events to stratigraphies established
elsewhere, particularly the Shetland facies developed in the Viking Graben of the North Sea
basin, suggesting a provincial similarity that is useful for large scale correlation.
         The main periods of deep - water sandstone development are within sequences K50
(early - late Turonian): 'Upper Lange Sandstones', K60 (late Turonian - Santonian): Lysing
Formation ('latest Turonian'- Coniacian) and 'Kvitnos Sandstones' (Santonian); K70 ('latest'
Santonian- middle Campanian): 'Nise Sandstones' and K90 (late Campanian - late
Maastrichtian): 'Springar Sandstones'. Long distance stratigraphic correlations, depositional
environments and sediment sourcing are presented and discussed.
         Intra - Late Cretaceous stratigraphic breaks are relatively rare, and difficult to identify
from the wireline log responses of the predominantly claystone intervals in this deeper water
area with the exception of the Cretaceous/Tertiary rifting event which shows variable but
sometimes significant truncation of the underlying Shetland Group.
         Biostratigraphy has therefore had an important role in the recognition, interpretation
and correct regional correlation of Late Cretaceous sequences in the offshore Mid - Norway
area.
BIOSTRATIGRAPHIC IMPACT ON THE RESERVOIR
ARCHITECTURE AND BASIN MODELLING OF THE GIANT
ORMEN LANGE GAS FIELD SPANNING THE CRETACEOUS /
TERTIARY BOUNDARY, OFFSHORE MID-NORWAY

M.A. CHARNOCK
Norsk Hydro, Research Centre, N-5020 Bergen, Norway
N.K. MÖLLER
Norsk Hydro Exploration and Production, N-0246 Oslo, Norway
L.I. COSTA, R.J. DAVEY, M. WELDON
Robertson Research International Ltd, Llandudno, North Wales, LL30 1SA, U.K.

The Ormen Lange Field in the Møre Basin, offshore Mid-Norway was discovered in 1997 with
the drilling of the 6305/5-1 well and is the first commercial deep-water discovery in the Mid -
Norway area and the second largest gas discovery in the Norwegian Sector. The reservoir
system comprises Maastrichtian to Danian deep marine, sand-rich turbidites spanning the K/T
boundary (figure 1). The reservoir has been cored in four wells, and significantly, both from an
industrial as well as academic perspective, three have a continuously cored K/T boundary
record and represent the most complete boundary sections in present day high latitudes.
          High-resolution   biostratigraphy using      both     quantitative   palynology and
micropalaeontology has had a significant impact on our understanding of the reservoir system.
This has been primarily focused on detailed intra-reservoir correlations and establishing a
stratigraphic framework, often below seismic resolution, of the five reservoir units. The
correlations show there is considerable variation in the depositional style and geometry of
these different units. In general, the oldest, i.e. Maastrichtian Jorsalfare Sandstone Unit is a
more uniformly correlatable sequence than the highly variable, amalgamated channel-fill
sequences of the younger, Lower Paleocene main reservoir Egga Sandstone Unit where a
series of dinoflagellate cyst events suggests the system attempted to compensate and adjust
to variations in topography through time. In the middle of the sequence are the Våle Tight and
Våle Heterolithic Units. The latter spans the K/T boundary (defined by the extinctions of P.
grallator and Heterohelix/Globigerinelloides spp.) which coincides with the onset of black
mudstones. The Våle Heterolithic Unit is a complex unit with deformed sandstones partly
interpreted as injection features and the overlying Våle Tight Unit is a thin unit of black
mudstones and is important to define biostratigraphically since it may act as a permeability
barrier during production. Dating of the whole reservoir sequence by calibrating selective bio. -
events to the Hardenbol et al. (1998) timescale indicates the system was deposited in <8Ma.
The Early / Late Paleocene boundary lies within overlying hemipelagic mudstones of the Våle
Formation, with planktonic foraminifera, and coincides with a transgressive event which
terminated sand deposition in the area. Study of the overlying Cenozoic sediments and the
recognition of a mid-Miocene stratigraphic break has provided information for basin modelling.
          Biostratigraphy has secondarily attempted to solve problems associated with reservoir
characterisation. Analysis of the reworking has revealed palynomorphs with a range of ages
(Permo-Trias. to Maastrichtian) and has provided useful information on sediment sources and
the uplift history. The reworking is generally in an 'inverted stratigraphy' and suggests the
progressive erosion of the source area with sediment derivation from a single point source.
Micropalaeontology has attempted to identify turbiditic and hemipelagic mudstones.
Widespread and continuous intra-reservoir mudstones act as permeability barriers. The
frequency of planktonic foraminifera and radiolaria characterise hemipelagic intervals and to a
lesser extent, diverse agglutinated foraminifera suites (sensu Winkler, 1985). The majority of
the mudstones, however, within the main Egga Unit have none of these indicators and may
represent discontinuous turbiditic mudstones and erosional remnants between channels.
MIOCENE MICROFOSSILS AS EVIDENCE OF
CONTAMINATION IN A MINERAL WATER DRILL SITE:
EXAMPLE FROM THE VIENNA BASIN

S. CORIC
Institute of Paleontology, Geo-Zentrum, Althanstrasse 14, 1090 Vienna, Austria
F. RÖGL
Museum of Natural History, Burgring 7, 1014 Vienna, Austria

The mineral water company „Vöslauer― drilled in the town Vöslau in the western part of Vienna
basin (Central Paratethys) for mineral water. The drill site is positioned at the down-faulted
western border of the basin. It penetrated Middle Miocene sandy gray marls the „Badener
Tegel― with interbedded gravel layers, with brown marls at 240 m, followed by transgressive
basal conglomerate. The borehole ended in Mesozoic limestones yielding mineral water.
Brown and grey marls contaminated the mineral water extracted in a preliminary pumping. It
was an essential requirement for the mineral water company to locate with precision the depth
and origin of the contamination.
         To investigate the origin of these sediments samples were taken for microfossil
analyses. The earliest sedimentation is documented by calcareous nannoplankton only. At the
top of the basal conglomerate at 240 m, light brown marls contain a rich nannoflora (Zone
NN4) with frequent Helicosphaera ampliaperta, which is absent in other samples.
Samples from 240 m up to 50 m belong to nannoplankton Zone NN5. By means of
foraminifera the section was correlated with the regional biozones. In particular, the lower part
(240 m to 190 m) corresponds to the upper part of Lower Lagenidae Zone. Praeorbulina
glomerosa glomerosa, characteristic of the lower part of the Lower Lagenidae Zone, has been
found only in brown marls of sample 240 m. In the upper part of the section (160 m to 75 m),
attributed to the Upper Lagenidae Zone Orbulina suturalis only was observed. The top of the
section (50 m to 30 m) belongs to the Agglutinated Foraminifera („Spiroplectammina―)
Assemblage Zone, corresponding to nannoplankton Zone NN6.
         In conclusion, based on the content of nannoplankton and foraminifera it was possible
exactly to locate the source of the contamination in the mineral water at 240 m and between
30 and 50 m. The origin of the brown marls was determined by nannoplankton as Zone NN4,
which occurred only at the basal level at 240 m; the grey marls have been dated as
Agglutinated Foraminifera Zone (NN6), which occurred only in the uppermost part of the drill
site.
DINOCYSTS FROM THE FINLAY LIMESTONE (ALBIAN),
CERRO DE CRISTO REY, NEW MEXICO, USA

W.C. CORNELL
Dept. of Geol. Sci., University of Texas at El Paso, El Paso, Tx 79968, USA

Outcrop samples of the Finlay Limestone, exposed on the west bank of the Rio Grande, in
southernmost Doña Ana County, New Mexico, have yielded numerous dinoflagellate cysts,
large numbers of bisaccate pollen, and rare trilete spores. Marls, nodular limestone, and
massive limestone beds (to 4 m thick) are present in the 40 meter-thick section.
         Cysts assigned to four, possibly five, genera in the Family Deflandreaceae are the
most abundant, contributing 25 – 75% of the cysts in the samples. Spiniferites species occur
throughout the section, averaging approximately 10% of the cysts in each sample.
Odontochitina species also occur in all samples but total fewer than 10 % of the cysts in each
one. Overall abundance and taxonomic diversity is influenced by facies – the massive
limestones yield low-diversity, Deflandreacean-dominated assemblages. Marly sequences, on
the other hand, yield both the largest numbers of cysts and assemblages of greatest diversity.
Nodular sequences fall in between in both diversity and cyst abundance.
         Although the outcrops lie less than 600 m (map) from an Eocene andesite pluton, the
cysts and pollen show no signs of thermal alteration, having TAI values (Pearson scale) of 1
or less.
THROUGH THE MICROSCOPE: A LOOK AT EARLY AND LATE
CHRISTIAN DIET IN NUBIA

L.S. CUMMINGS
Paleo Research Institute, 2675 Youngfield St., Golden, Colorado, 80401 USA

Coprolites associated with individuals excavated from two cemeteries at Kulubnarti in
Sudanese Nubia provided a rich record of pollen, phytoliths, macrofloral remains, and bones,
reflecting diet. These cemeteries represent ancient agricultural cummunities of the early
Christian period (AD 550-750) and the later Christian period, which terminated in the mid-15th
century. Study of these coprolites is unique in that each coprolite is associated with a body,
providing age and sex information. Further population comparisons may be made between
observations of nutritional completeness, based on the coprolite evidence, and evidence of
nutritional deficiencies noted by separate hair and skeletal analyses. In addition, diachronic
comparisons of diet are possible.
STATISTICAL MODELLING OF ECOLOGICAL SIGNALS: A
NEW METHOD FOR DEVELOPING ORE ROBUST
APPLICATIONS OF PALAEOENVIRONMENTAL
INTERPRETATIONS ON AN INDUSTRIAL DATASET

B. DALE
Geology Dept., University of Oslo, PB 1047 Blindern, N-0316 Oslo, Norway
A.L. DALE
GeoResearch Consulting, 2100 Skarnes, Norway
I. PRINCE
Statoil, Furusbeen 50, N-4035 Stavanger, Norway

Previous work by B. Dale and co-workers has developed methods for statistical modelling of
ecological signals (SMES) from present-day dinocysts. Here we report the first test of their
application to industrial biostratigraphy – on a palynology dataset provided by Statoil. The
dataset was from 4 wells along an onshore-transect from the Norwegian North Sea. The data
available was semi-quantitative (c. 100 specimens per sample counted and the remainder of
the slide scanned) and all counted by the same contractor (taken from a multiwell study) for
consistency. The wells were part of a larger study on palaeoenvironments completed by
Statoil on approximately 48 wells. Some of the traditional multivariate statistical methods had
been tried but without success. The abundances of individual species (usually the marker
species for regional flooding surfaces as these were present in varying numbers as opposed
to being only rare) were plotted for each well along an offshore/onshore transect for each time
slice, and similarities between the profiles were noted and mapped. Using a proposed model,
these similarities were then compared with the seismic facies and environmental maps
presented. The palaeoenvironment was thus partly understood from the larger previous
study, allowing the SMES method to be tested against a control method.
           The SMES application was tested ―blind‖ (i.e. with no prior knowledge of the age of
the sediments, location of the wells, or results from the larger Statoil project). Correspondence
analysis was run on the dinocyst data from each well. The resulting plots showed clear, and
consistent spreads of species along the first two axes, allowing the identification of the
statistically most important species, and their relative positions along the two statistically most
important suggested ecological trends. Tracking these species down-hole revealed a
consistent pattern of changing relative values between these two ecological trends, allowing
the identification of major shifts between the two at various horizons. Two major shifts were
identified in each well that could be correlated between all four wells. Comparing the patterns
of distribution of species along the main axis suggested this to probably represent the nearer-
shore/oceanic signal of Dale (1996). This interpretation allowed us to: 1) Suggest the
orientation of the well sites relative to a paleo-shoreline, and 2) To identify the major ecological
shifts down-hole as expressions of transgressions/regressions. The final comparison between
these interpretations and Statoil results was very encouraging – the suggested orientation of
the wells agreed with their positions interpreted from the larger regional study, and the major
ecological shifts from the SMES application corresponded exactly to the Statoil flooding
surfaces. This first test strongly suggests these methods to offer a much quicker, and more
robust application for palaeoenvironmental interpretations from the dinocysts in
biostratigraphic datasets.
FUNGAL SPORES FROM COPROLITES: A MEANS OF
DETECTING HERBIVORE DENSITY

O.K. DAVIS
Arizona-Nevada Academy of Science, & Department of Geosciences, University of Arizona,
Tucson, AZ 85721-0077 USA

During the historic period, spores of the dung fungus Sporormiella are abundant in lake and
cave sediment where livestock are plentiful in the western United States. Sporormiella spores
often exceed 50% of the upland pollen sum in samples from corral ponds and bed-grounds,
and routinely reach 2-3% in lake and marsh samples in pastoral areas.
           Sporormiella spores are comparatively rare during the Holocene, but they reach
values of 2-4% in Pleistocene samples from lake sediments. Sporormiella spores are directly
linked to extinct megaherbivores by their presence in mammoth dung from Bechan Cave,
Utah. A precipitous decline of Sporormiella percentages after 10,800 yr B.P. apparently marks
a decline of herbivore density in lake cores from Idaho, Colorado, and other sites in the
western United States.
THE SCIENCE OF COPROLITE ANALYSIS: THE VIEW FROM
HINDS CAVE

G.W. DEAN
Historic Preservation Division, Office of Cultural Affairs (Rm 320), 228 E. Palace Ave., Santa
Fe, NM 87501 USA

Nearly a century of human coprolite analysis includes specimens from all over the world and
from the dawn of human existence onward. Analytical techniques have evolved with
successive generations of researchers willing to explore the ecology of the fecal deposit.
Archaeological analyses in the New World, particularly Peru and the North American
Southwest, are especially noteworthy due to excellent preservation of sometimes enormous
numbers of specimens from single archaeological sites.
         My 1978 analysis of 100 specimens from perhaps the first identified prehistoric latrine
in North America is a case in point. These specimens represent about 10% of an
archaeological deposit with bracketed dates of 5710 +/- 80 and 5590 +/- 80 radiocarbon years
before present (uncorrected) from the top and bottom of the deposit, respectively.
         The analysis of these 100 specimens provided detailed data on the contents: pollen
spectra, plant remains, insect remains, animal bone and fur, and attempts were made to find
evidence of intestinal parasites, occult blood residues, viruses, and most recently, sex
hormones. An experiment, conducted with volunteers as part of the archaeological analysis,
produced 82 modern specimens yielding data on the rate of elimination of specific pollen
grains from the human system.
         Subsequent coprolite analyses in the American Southwest have focused on fewer
specimens from any given time period. Some ideas, such as using pollen concentrations as
an indication of recent ingestion, are largely untested for validity. Unwarranted assumptions
have also crept into this most anthropological of sciences.
         This paper provides new perspectives resulting from my re-examination of my 1978
pollen data. Of particular interest are the results of pollen concentration calculations for both
the prehistoric and the modern specimens, and the results of a test to determine the minimum
number of coprolites that must be examined to reach a degree of redundancy of data.
         The 1978 study remains the most comprehensive analysis of such a large sample of
coprolites from a single archaeological site and time period. Yet, this paper shows that there is
ever more to learned from these and other coprolite specimens. The application of specialized
techniques at the microscope, such as Intensive Systematic Microscopy, to locate and
quantify rare pollen types needs to be explored. Parasitological studies of human coprolites
will benefit from experimental data to determine the fate of the constituents of human feces
ingested by dogs. Easy and valid ways to express the abundance of macroremains in a
coprolite are also needed.
PALYNOLOGICAL CALIBRATION AND CONFIRMATION OF A
SEQUENCE STRATIGRAPHIC/SEDIMENTOLOGIC MODEL
FOR THE OFICINA FORMATION (EARLY MIOCENE) AT
PETROZUATA, VENEZUELA
T.D. DEMCHUK
Conoco Inc., Integrated Interpretation Center, Houston, TX 77252-2197, USA
E. GONZALEZ-GUZMAN
Consultores Geostrat C.A., Los Altos de Santa Fe, Via Principal, Sector el Saco, Villa El Eden,
Edo Sucre, Venezuela
J.R. SUTER
Conoco Inc., Integrated Interpretation Center, Houston, TX 77252-2197, USA

Palynological assemblages are most valuable data for the recognition and calibration of
sequence stratigraphic systems tracts, and for the confirmation of depositional
paleoenvironments as interpreted from sedimentological observations, seismic facies
analyses and wireline log stacking patterns. Reservoir strata of the Oficina Formation from
Petrozuata, are a highly complex amalgamation of deltaic, estuarine, and fluvial
paleoenvironments. Sandstone bodies are vertically and laterally variable, and the recognition
of this variability in the subsurface based on integrated stratigraphic models is critical to a
successful drilling program and hydrocarbon exploitation. Palynological analyses of the shales
within reservoir intervals, and the resulting assemblages helps formulate palynological
―fingerprints‖ which can then lend confirmation to sedimentological observations. This
palynological fingerprint is an interpretation of the paleoecology based on the pollen, spore,
and dinoflagellate content of the assemblage. Subsequently, these varied palynological
fingerprints can aid in the development and confirmation of a sequence stratigraphic model
through the recognition of highstand and associated maximum flooding surfaces and the
identification of systems tracts.
         Reservoir strata of the Oficina Formation at Petrozuata are early Miocene in age,
Verrutricolporites rotundiporus Zone, Psiladoporites minimus Subzone. Generally, palynofloral
assemblages contain abundant freshwater pollen and varied spores (Verrucatosporites
usmensis) with sometimes dominant palm pollen (Mauritiidites sp.). Variations in the relative
abundances of terrestrial pollen, versus mangrove pollen and dinoflagellates are characteristic
of the varied paleoenvironments of this prograding paralic succession. At least four major
flooding surfaces are recognized palynologically within the main reservoir interval, and these
can be calibrated to third-order cycles on the worldwide sea-level chart. These flooding
surfaces are characterized by high abundances of mangrove pollen (predominantly
Zonocostites ramonae) as well as varied dinoflagellate taxa including Cribroperidium
tenuitabulation, Lingulodinium machaerophorum, Spiniferites sp., and Hemicystodinium
zoharyi. Dinoflagellates are ubiquitous in the majority of palynological assemblages, with the
exception of those from the lowermost sequences of the reservoir interval. The quantity and
low diversity in the majority of these assemblages indicate a nearshore, inner neritic setting.
However, a maximum flooding surface dated at 18.0MaYrs is of great regional extent
suggesting that during this time the entire Petrozuata area was completely inundated by
marine waters. Lateral variations in these high abundance, high diversity dinoflagellate
assemblages characterizing this maximum flooding surface indicates paleowater depths of
middle neritic in the northeastern portion of the Petrozuata property.
DATA INTEGRATION AS THE KEY TO ROBUST RESERVOIR
MODELS

C.N. DENISON, R.C. PREECE
EPTC, ChevronTexaco, San Ramon, CA, USA

Creation of a viable reservoir model should bring together a multiplicity of differing sub-surface
disciplines. Data assimilation, integration, and iteration are the keys to effective reservoir
modeling. Examples are presented to illustrate some of these aspects.
         Industry experience is that history matching varies significantly: reservoir models of
producing oil fields may not flow. Reservoir engineers have to resort to data manipulation,
typically gross changes to permeability, porosity and faults, to force a history match, but this
results in progressive divergence from reality into the future.
         Understanding the flow-unit geometry within the reservoir relies upon a robust
stratigraphic framework that is based on 1D well picks and core-based depofacies, then
expanded to 2D well log correlation panels, using sequence stratigraphic concepts. Failure to
accurately capture the subsurface architecture at this initial stage renders all subsequent work
moot. Detailed core description and correct depofacies identification is operator-dependent,
but in common with other basic geological disciplines, there is a shrinking expertise base.
         Sequential Gaussian Simulation is one method for populating the 3D inter-well space,
but typically generates a salt-and-pepper property distribution that is geologically unsatisfying.
Object-based modeling, the creation and distribution of 3D objects, produces a more realistic
and geologically satisfying model of internal reservoir complexity. Constraints on the
dimensions and properties of the objects ultimately depends on our knowledge of modern
processes and outcrop analogs.
         Essential to generate and test a reservoir model are Dynamic Engineering Data, the
large number of continuous measurements taken during oil-field development and production.
Datasets such as original pressures and temperatures, pressure declines, individual well
production history, and water-cuts have to be logically reconciled with the stratigraphic model.
         Modern 3D seismic surveys can produce remarkable stratigraphic resolution, but at
the reservoir scale there is often something lacking, due to a variety of factors such as
acquisition and processing problems, depth to reservoir, or simply the inherently low vertical
seismic resolution. Despite these limitations, 3D seismic is the only volume-based dataset,
and has to be integrated into a robust reservoir model.
         Biostratigraphy plays a small but important role. Standard biozonation scales restrict
their application to exploration activities: few reservoirs span sufficient time for standard
biozones to be useful. At the reservoir scale, various methods have been developed, mainly
based on the ecozone concept for field-wide correlations. Predictable properties from this
approach are leveraged into the reservoir model. The future of applied biostratigraphy
depends on electronic database interface, the ideal platform for deployment of interpreted
biostratigraphic data into the reservoir characterization domain.
UPPER MIOCENE – PLIOCENE SUBSURFACE
PALYNOLOGICAL REFERENCE SECTION FOR THE CRUSE,
FOREST AND MORNE L’ENFER FORMATIONS, FOREST
RESERVE FIELD, TRINIDAD, WEST INDIES

L. DE VERTEUIL
Latinum Ltd., P.O. Box 575, Port of Spain, Trinidad, WI
N. JOHNSON
Geological Services Laboratory, Petrotrin Ltd, Pointe-à-Pierre, Trinidad, WI

The Cruse, Forest and Morne L'Enfer formations represent the upper Miocene – Pliocene
proto-Orinoco deltaic succession in the onshore southwest Southern Basin of Trinidad. Prior
to offshore discoveries this was the main oil producing area of Trinidad and remains both
geographically and stratigraphically central in studies of the upper Neogene regional geology.
The giant Forest Reserve Field produces from Cruse and Forest reservoirs, with cumulative
production of over 275 mbbl of oil.
         One hundred and twenty-nine conventional core samples, from an overlapping,
continuously cored interval from wells FR670 and FR691, provide the basis for the present
study. The FR670/691 composite contains a co-type Cruse section, the type section of the
Forest Formation and a representative lower Morne L'Enfer section. A further 115 core and
cuttings samples from four additional Forest Reserve wells compliment and provide lateral
control on data from the FR670/691 section, including an upper Morne L'Enfer interval.
Hopping's earlier analysis of the FR670/691 section was integral to the pioneering pantropical
palynological studies by Shell. The present fully composited section from Forest Reserve
spans the Grimsdalea magnaclavata, Pachydermites diederixi, and Echitricolporites mcneillyi
Caribbean intracontinental zones of Germeraad, Hopping and Muller (1968).
         Quantitative palynomorph and palynofacies analyses, integrated with e-log facies and
core descriptions, permit re-evaluation and refinement of existing regional zonations within a
sequence stratigraphic framework. At the field scale, the delineation of acme events and
taphonomic/paleoenvironmental interpretation of the assemblages contributed to overall
reservoir characterization.
         The transition from calcareous basinal Lengua Formation shaley marls to essentially
non-calcareous Lower Cruse Clay, representing the distal edge of the advancing deltaic
system, is transitional over ca. 45 m (150 ft). This transition is characterized by decreasing
dinocyst abundance, particularly of the offshelf genera Impagidinium and Nematosphaeropsis,
within a palynofacies still dominated by marine amorphous SOM. Above this marine clay, the
Lower Cruse – Middle Cruse unconformity represents the most significant basinward shift in
palynofacies and depositional environments observed in the study, heralding the arrival of the
Orinoco system in the Forest Reserve area. Above this level, five major sequences (S-0 – S-
4) are delineated, generally corresponding to the Middle Cruse, Upper Cruse, Forest, Lower
Morne L'Enfer and Upper Morne L'Enfer.
ANALYSING THE INTESTINAL CONTENTS OF ANCIENT
ICEMEN (ÖTZI AND LONG AGO PERSON FOUND):
REVEALING ITINERARIES AND DOMICILES

J.H. DICKSON
University of Glasgow
P.J. MUDIE
Geological Survey of Canada, Dartmouth, Nova Scotia
R. HEBDA
Royal British Columbia Museum, Victoria, British Columbia

The study of the microscopic and macroscopic plant contents of the alimentary canals of
frozen mummies can reveal not just the composition of the last meals but potentially help to
elucidate the last itineraries and domiciles of the deceased. This is discussed with relevance
to two icemen: Ötzi, the 5,300 year old man from the Alps, and Long Ago Person Found, the
550 year old man from northernmost British Columbia. In the case of Ötzi was his domicile to
the north or south and which valley did he travel through? In the case of Long Ago Person
Found, did he come from the coast or from the interior? Chenopodiaceae pollen, particularly
new SEM studies of saltmarsh and salt desert Salicornia species are crucial in making this
decision.
VARIATIONS IN UPPER OLIGOCENE – LOWER MIOCENE
DINOFLAGELLATE CYST ASSEMBLAGES AND THEIR
RELATIONSHIP TO GLACIO-EUSTATIC SEA-LEVEL
CHANGES, ONSHORE JYLLAND, DENMARK

K. DYBKJÆR
Geological Survey of Denmark and Greenland (GEUS), Thoravej 8, DK-2400 Copenhagen NV,
Denmark

A sequence stratigraphic subdivision of the Upper Oligocene – Lower Miocene siliciclastic
succession in the central parts of Jylland, Denmark, has been recently published. The variation
in the dinocyst assemblages in the lower three sequences, A-C, is presented here, and the
response to eustatic sea-level changes is discussed.
         Sequence A (latest Chattian) shows a rich and diverse dinocyst assemblage in the
lower, fully marine part (the TST). In the upper, gradually shallowing part (the HST), the
dinocyst abundance and diversity decreases while the relative abundances of freshwater algae
and non-saccate pollen increases. Deflandrea phosphoritica shows a distinct increase in
abundance towards the upper sequence boundary, possibly as a result of increased nutrient
supply. Furthermore, in the most proximal parts of the study area, Homotryblium plectilum
appears in the uppermost part of the sequence.
         Sequence B (latest Chattian? – early Aquitanian) was deposited in a restricted marine,
low salinity environment. The dinocyst assemblage is dominated by Homotryblium spp.,
Dapsilidinium pseudocolligerum and Spiniferites spp. Within the genus Homotryblium, a lateral
variation in the distribution was found, with H. plectilum being most abundant in the proximal
parts of the study area (possibly reflecting a high freshwater influx) while H. tenuispinosum
dominated the more distal parts of the study area (thought to be less influenced by freshwater).
         A major unconformity is present between Sequences B and C. Sequence C (early to
mid-Burdigalian) was deposited in a more open marine, probably shelfal environment. The
dinocyst assemblage is generally characterized by a dominance of Spiniferites spp.,
Operculodinium centrocarpum, Impletosphaeridium insolitum and Systematophora
placacantha. Furthermore, the more open marine conditions are clearly reflected in a higher
abundance and diversity of dinocysts. Several new species appear, while Homotryblium spp.
only occurs sporadically except for in the most proximal areas where this genus is common.
         The datings of the studied sequences have been compared with earlier published
curves of eustatic sea level variations based on variations in oxygen isotopes, and with inferred
glacial maxima. The close correlation between these data strongly indicate that eustatic sea-
level changes were the main controlling factor on the observed changes in the depositional
environment and in the dinocyst assemblages. Local structural elements, however, also
influenced the depositional environment both by acting as discrete topographic barriers and
also by controlling the location of spit development.
DINOFLAGELLATE CYSTS FROM THE CHESAPEAKE
BAY IMPACT STRUCTURE – IT WAS A BLAST!

L.E. EDWARDS
U.S. Geological Survey, 926A National Center, Reston, VA 20192 U.S.A.

The Chesapeake Bay impact structure was formed by a comet or meteorite that struck the
continental shelf of the eastern United States (southeastern Virginia) about 35.5 million years
ago. As in other sites with a marine sedimentary target, the resultant impact-generated
breccia consists of rocks and sediment that were present at the time of impact, which were
then redeposited under conditions that include various combinations of shock, heat, collapse,
tsunamis, and airfall. Impact-generated deposits within the crater contain dinoflagellate cysts
that are fused, curled, folded, bubbled, broken, pitted, and (or) partially melted.
         Samples from the impact-matrix deposits contain Cretaceous to late Eocene
dinocysts. Late Eocene dinocysts such as Cordosphaeridium funiculatum and Batiacasphaera
baculata are coeval with the impact. Older specimens, most abundantly Pentadinium
goniferum, Pentadinium membranaceum, and Dracodinium varielongitudum, were derived
from older units in the Virginia Coastal Plain and redeposited into these younger, impact-
related deposits.
         The preservation of the dinocysts and other palynomorphs in the impact-matrix
material is striking. Most notably, the overall preservation would be categorized as poor. In
some instances, one can recognize material of dinoflagellate origin, but cannot identify it to
species or even genus or family. Fragments are much more common than whole or nearly
whole specimens and organic debris tends to occur in fused clumps. But the adjective "poor"
does not adequately reflect the wide variety of impact-related damage imparted on the
specimens. I will illustrate the most prominent preservation types.
         The alterations of dinocysts in impact-matrix deposits constitute a relatively unstudied
aspect of taphonomy. In this case, Cretaceous, Paleocene, and Eocene dinocysts have
experienced two episodes of deposition. During the latter episode, in late Eocene time, the
events that preceded final burial included heat, shock, abrasion, and in some cases, airfall.
Altered dinocysts are also found in post-impact deposits as young as late Miocene (27 million
years after the impact). These specimens were exhumed and deposited yet again, perhaps
reflecting movement along compaction-related faults.
         Fused, folded, partially melted, or bubbled microfossils, together with broken cysts,
may offer new insights into cratering mechanics, and the specific kinds of damage (heat vs.
shock-induced breakage) may provide important constraints to the understanding and
interpretation of the crater history. Furthermore, since these altered microfossils come from a
known impact structure, they may serve as guides for recognizing impact-related deposits
elsewhere.
DINOFLAGELLATE AND PALAEOMAGNETIC STRATIGRAPHY
OF EOCENE TO OLIGOCENE SEDIMENTS FROM THE
NORWEGIAN-GREENLAND SEA

J. ELDRETT, I.C. HARDING
School of Ocean and Earth Sciences, Southampton Oceanography Centre, Southampton
University, European Way, Southampton, SO14 3ZH, UK
J.V. FIRTH
Ocean Drilling Program, College Station, TX, USA.

         The presence of abundant age-diagnostic dinocysts at Site 913B (ODP Leg 151), Site
338 (DSDP Leg 38) and Site 643A (ODP Leg 104) has enabled the development of a new
high-resolution biostratigraphy for the Eocene-Oligocene interval in the Norwegian-Greenland
Sea.     This is particularly important as the calcareous microfossils usually used for
biostratigraphy are generally absent in these high latitude Eocene-Oligocene sediments due to
dissolution. In addition, the development of a new magnetic reversal stratigraphy for the
Norwegian-Greenland Sea has enabled independent age control and allowed the dinocyst
biostratigraphy to be firmly tied into the global geomagnetic timescale for this period.
         The high-resolution study employed for this project has identified dinocyst
assemblages that show affinities with those from the North Sea and North Atlantic, allowing
regional correlation.
FORGING A PATH FOR BIOSTRATIGRAPHY

M.B. FARLEY
Geology, BA 206, University of North Carolina at Pembroke, Pembroke, NC 28372, USA

Biostratigraphy‘s future depends on recognizing what we have accomplished in academia and
industry, building on that base, and effectively marketing our technologies and knowledge to
the broader scientific and industrial community.
         In micropaleontology, 40 or more years of concentrated effort has led to valuable
technology as well as important spin-offs outside biostratigraphy and even outside
paleontology. We have a general global stratigraphic framework from continents to deep
oceans in the Phanerozoic. In some basins, we have biostratigraphies with average resolution
at 100 ky or better. In addition, our work has been vital to development of information on
phylogenetic pattern and mode, paleoenvironment, and basin thermal history.
         Academic micropaleontology has been notably successful at providing a biological
context, creation of new techniques such as stable isotope and multivariate analysis, and
analysis of high quality sections. Industrial micropaleontology has provided geological context,
integration with new techniques (seismic stratigraphy, well logs), and analysis of dense
sections with high potential resolution.
         Technical progress depends on improved communication between academic and
industrial paleontologists, a standard stratigraphic framework, analysis of all fossil groups
together, and improved integration of paleontology with other data. Technical progress is not
sufficient, however.
         We need to market biostratigraphy more effectively to the larger geologic and biologic
communities. One important approach is infiltration. By participating outside paleontology, we
can stimulate outside interest in what we can contribute. A micropaleontologic session is
useful within the specialty, but getting our message across to the wider population by
appearing in the sessions they attend is equally valuable. Informal infiltration is probably even
more important. We also need to be more aggressive in ensuring that biostratigraphy is more
effectively incorporated in undergraduate and graduate education.
         I don‘t have all of the answers to successful marketing of the value of our discipline.
This is an area where any paleontologist can make a substantial contribution, and I hope to
stimulate thinking about this.
MODELING BIOSTRATIGRAPHIC DATA USING FUZZY
INFERENCE SYSTEMS

A.C. GARY, D.W. JOHNSON
Technical Alliance for Computational Stratigraphy, Energy and Geosciences Institute,
University of Utah, 423 Wakara Way, Suite 300, Salt Lake City, UT, USA

Communicating biostratigraphic results in a sequence stratigraphic context is an increasingly
important objective in the application of biostratigraphy. Biostratigraphers need to find
effective ways of relating quantitative paleontological data to descriptive models, such as
sequence stratigraphic models. Using a fuzzy logic inference system we are able to solve two
of the basic problems in meeting this objective. One is how to relate quantitative microfossil
data to descriptive concepts (e.g., lowstand systems tract, etc.) in a consistent manner.
Presently, this is done by a multi-step ad hoc procedure of the biostratigrapher creating
descriptive interpretations from the quantitative biostratigraphic data and then qualitatively
assessing its sequence stratigraphic meaning. Using a fuzzy logic the biostratigrapher can
create conceptual models that will directly accept quantitative microfossil data and produce a
quantitative assessment of their sequence stratigraphic relevance.
A second problem is that even though many of the microfossil disciplines provide
complementary paleoenvironmental information, the existing models relating microfossil data
to sequence stratigraphic models tend to be specific to a discipline, such as foraminifera or
palynomorphs. Often the result is that the biostratigrapher must somehow reconcile the
sequence stratigraphic implications of multiple biostratigraphic interpretations.         This
fragmentation of models is due in part to the tremendous amount of information that is
collectively encompassed by the microfossil sub-disciplines (e.g., foraminifera, palynology,
calcareous nannoplankton, etc.) necessitating biostratigraphers to specialize in one or two of
them. Using simple Boolean logic statements the fuzzy inference system allow multiple
disciplines to be unified in a single conceptual model.
QUANTITATIVE METHODS FOR APPLIED MICROFOSSIL
BIOSTRATIGRAPHY
F.M. GRADSTEIN
Geology Museum, P.O. Box 1172 Blindern, N-0318 Oslo, Norway
F.P. AGTERBERG
Geomathica, 490 Hillcrest Ave, Ottawa, Ont., Canada
Q. CHENG
Dept. of Geology, Univ. of York, York, Ont.,

Fancy graphical results, easier data input and easier data operation are making quantitative
stratigraphic methods more attractive to the complex datasets of exploration biostratigraphy.
Two methods, Graphic correlation and Ranking & Scaling are most prominent, with a third
CONOP holding promise.
         Graphic correlation, represented by program GRAPHCOR is a deterministic method
employing interpolation of successive well data in a semi-objective bivariate plot mode. The
method uses order and thickness spacing of events and operates best with datasets having
both first and last occurrences of taxa. The final answer is a composite well with maximum
taxa ranges. It is best suited for small data sets and requires selection of an initial reference
well that is stratigraphically updated by the other ones in succession.
         Constrained optimisation, embodied by program CONOP is an improvement on
graphic correlation. It operates inverse in that it picks an initial solution that is updated in a
'kind of multidimensional graphic correlation' manner, using simulated annealing and penalty
scores. It uses event order, event crossover, and thickness spacing; datasets best have both
first and last occurrences of taxa and can be small to medium size. It attempts to find
maximum or most common stratigraphic ranges of taxa and treats all wells simultaneously. A
good example of its potential is a recent application to wells in the Taranaki Basin.
         Ranking and scaling is a probabilistic method, embodied by programs RASC & CASC.
It uses event order to construct a most likely or average sequence of events, that is scaled
using crossover frequency of all event pairs; it extensively uses stratigraphic error analysis
and has several correlation options. RASC & CASC operates on all wells simultaneously, is
very fast, handles large and complex data sets and is relative insensitive to noise. A
demonstration version and manual can be downloaded from http://q-strat.org.
         The latest editions of the program (versions 17 and 18) have extensive colour
graphics output and an interactive database manager. Attempts are underway to semi-
automate data input from standard range charts. Examples of modern exploration zonations
are offshore Norway and in the Mississippi delta complex.
THE STRATABANKTM CONCEPT – WWW-BASED
STRATIGRAPHY WITH LARGE FOSSIL DATABASES

F.M. GRADSTEIN, Ø. HAMMER, N. STÖTZER
Geology Museum, University of Oslo, N-0318 Oslo, Norway
C. CERVATO
Dept. of Geol. & Atm. Sci., Iowa State U., Ames IA 50011, USA
M. SMELROR
Geological Survey of Norway, Trondheim, Norway
R. WILLIAMS, S. FINNESTAD
Norwegian Petroleum Directorate, 4001 Stavanger, Norway

A joint initiative of the Geology Museum of the University of Oslo, leading petroleum
companies, and the Norwegian Petroleum Directorate is leading to the creation of the
             TM
Stratabank system. This new concept is applied to a relational database of all fossil records
in all exploration wells from offshore Norway and baptized NORGES – Network of Offshore
Records of Geology and Stratigraphy. This economically powerful and scientifically valuable
project is the result of over 40 years of highly successful drilling in the Mesozoic and Cenozoic
sedimentary wedges in the North Sea, offshore Norway and the Barents Sea. It involves more
than 1000 wells spanning over 20 degrees of latitude in the boreal realm. A master dictionary
of foraminiferal, dinoflagellate, radiolarian, nannoplankton, diatom, spore and miscellaneous
taxa is adding up to over 11000 taxonomic entities, including their junior and/or senior
synonyms, and involves over 1000 stratigraphic events. The dictionary may be linked to a
digital atlas.
                The main advantages of storing such exploration record in a relational database
system using Oracle or MYSQL is that it can be probed in an intelligent manner. It must be
remembered that different operators and a variety of European consultants generated the
fossil distribution charts and events. The resulting record is non-standardized and can be
idiosyncratic and noisy. Its digitization is a slow and tedious manual job, executed as soon as
the well records are released to the public after two years. In-house binary consultant
taxonomy must be standardized with the help of exploration stratigraphy manuals, and
suspected caving records must be tagged.
                With the help of modern tools like age vs. depth diagrams, burial graphs that
also cumulate paleo-water depth, regional chronograms tied to the standard time scale, and
correlation charts with events of higher stratigraphic fidelity, the relational record is made
useful to both exploration stratigraphy and to scientific studies of basin dynamics. Intelligent
database access and expertise to translate the fossil record stratigraphically and
paleobathymetrically is one of the key issues with such WWW-based records that the
             TM
Stratabank       concept is capable of offering exploration biostratigraphers in this new
millennium.
DID SHEEP/GOAT EAT UP THE NEOLITHIC FOREST? –
PALYNOLOGY OF SHEEP/GOAT FAECES FROM
PREHISTORIC PILE-DWELLINGS OF SWITZERLAND

J.N. HAAS
Department of Botany, University of Innsbruck, Sternwartestraße 15, A-6020 Innsbruck,
Austria

A review of the pollen and macrofossil content found in prehistoric sheep/goat dung pellets
from pile-dwelling sites in Switzerland reveals interesting foddering trends towards
understanding prehistoric agricultural techniques during the Neolithic Period (4300-2200 BC):
         1. Most faeces analysed palynologically represent fodder consumption in winter or
early spring near or within the former settlements.
         2. Leaves and twigs of wintergreen plants such as Rubus fruticosus s.l. and Abies
alba were an important fodder resource.
         3. Additional foddering with early flowering twigs from shrubs such as Corylus
avellana and Alnus spec. was done in early spring in times of shortage.
         4. Foddering of goat/sheep with food garbage (e.g. cereal grains or cereal waste
products) seems to have been the exception during prehistoric times.
         5. Winter-Foddering of prehistoric goat/sheep with dry tree leaves and twigs gained by
pollarding or shredding in the previous summer (e.g. Tilia spec. or Ulmus spec.) was obviously
less common than known from historical times.
         All in all, the foddering techniques used for goat/sheep during the Neolithic and
Bronze Age Period point to the direct use of all available plant resources in winter and early
spring. The results do not support the idea and historically known tradition that large quantities
of plant fodder were stored in late summer and autumn for such animals in order to have
enough fodder in winter. However, such an agricultural technique might have existed
prehistorically for larger livestock, such as cows.
THE ORIGIN OF LOWER DEVONIAN SPORE-RICH
COPROLITES

K. HABGOOD
Dept. Earth Sciences, Cardiff University, P.O. Box 914, CF10 4YE

Small (less than 5mm long), spore-rich coprolites are common in certain Upper Silurian and
Lower Devonian horizons within the lower Old Red Sandstone group. Two L. Devonian
assemblages of terrestrial fossils, one preserved in fluvial sedimentary rocks in the Welsh
Borderland and the other in the siliceous Rhynie Chert from Aberdeenshire, include unusually
abundant and diverse coprolites.
         The two assemblages, although similar in age and both preserved amongst plant
fossils and organic debris, differ significantly in preservation and taphonomy. Coprolites from
the Welsh Borderland are coalified and relatively compressed, and preserved in transported
sediments. Conversely fossils silicified within the Rhynie Chert were preserved more rapidly
and much closer to their source if not in situ. Coprolites from both sites are diverse in
morphology and content, and comparison of the two assemblages reveals interesting
differences, but in each case spore-rich coprolites comprise a significant proportion of the total
faecal assemblage, and spores contained within the coprolites are apparently well-preserved
and relatively rarely damaged.
         Spore populations present within faeces from these assemblages provide clues to the
nature of the coprolite-producing fauna and their diet. This and further evidence, ranging from
the nature of the primary productivity available to Lower Devonian terrestrial fauna, to the
results of experimentation using modern analogues, suggest that spores may not have
provided a good source of nutrient for early terrestrial animals, and point to other origins for
these spore-rich coprolites.
EXPRESSIONS OF SEQUENCE PALYNOSTRATIGRAPHY
FROM THE GREENHORN MARINE CYCLE (CENOMANIAN-
TURONIAN) OF THE WESTERN INTERIOR BASIN, USA
A.J. HARRIS
School of Applied Sciences, University of Glamorgan, Pontypridd, Mid-Glamorgan, CF37 1DL,
UK

The wealth of geological data on the Cenomanian-Turonian sequences from the Western
Interior Basin allow a highly-integrated analysis of the palynostratigraphic expressions of
eustatic and associated environmental fluctuations. As these sequences were deposited in an
actively subsiding foreland basin, their study offers a number of advantages over other
sequences of equivalent age. Numerous dated bentonites allow high-resolution (bed-by-bed)
correlation between sections some hundreds of kilometres apart, and provide a detailed
chronostratigraphic framework. Limestone-shale couplets (of Milankovitch origin) from the
eastern pelagic carbonate ramp and central hemipelagic trough are correlatable with
marginal-marine and proximal parasequences deposited at the rapidly subsiding western
basin margin. High-resolution chronostratigraphic comparisons of dinoflagellate cyst species
from these very different marine environments across the seaway have allowed them to be
associated with water temperature, salinity, shoreline-proximity and bathymetry.
         The Greenhorn cyclothem (Lower Cenomanian-Middle Turonian) was deposited
within the Western Interior Basin over a second-order eustatic cycle, at a time of global first-
order highstand. The environments studied from the Amoco Rebecca Bounds Core from
Kansas, range from marginal marine through proximal to distal shelf environments within the
transgressive systems tract, and return to a proximal shelf environment in the highstand
systems tract. Dinoflagellate cyst assemblages are indicative of these environments and
support models for circulation in the epicontinental seaway that linked the boreal ocean to the
north with the subtropical Tethys to the south. Superimposed third-order eustatic fluctuations
are responsible for lithological (member-scale) variations in the sequences and although at
the limits of sampling resolution, can be identified using changing dinoflagellate cyst
assemblages.
         The Cenomanian-Turonian boundary occurs shortly before a combined first-, second-
and third-order maximum flooding interval. A high-resolution study of boundary sections
across the basin allows the synchronicity of sequence biostratigraphic events to be assessed
in finer-scale sequences and parasequences. Fourth-order eustatic fluctuations forced
changes in water-mass characteristics and affected macrofaunal distribution. Their flooding
surfaces and progradational highstands can be correlated between proximal and distal shelf
environments using the dinoflagellate cyst assemblages. The parasequences/bedding
couplets do not show consistent responses in dinoflagellate cyst assemblages but do show
characteristic palynofacies fluctuations that suggest variations in terrestrial input to the basin.
Dinoflagellate cyst assemblages also aid in the sequence stratigraphic reinterpretation of the
lithostratigraphy from marginal/shallow-marine environments.
CARIBBEAN TERTIARY DINOFLAGELLATE ASSEMBLAGES

J. HELENES
Departamento de Geología, CICESE, km 107 Carr. Tijuana-Ensenada, Ensenada, Baja
California 22860, México
I. PAREDES, D. CABRERA
Sección Geología, INTEVEP, S.A., Apartado 76343, Caracas 1070-A, Venezuela
A. DEL VALLE-REYES
Instituto Mexicano del Petróleo, Gerencia en Geociencias, Eje Central Lázaro Cárdenas 152,
D.F. 07730, México


Tertiary strata from around the Caribbean basin contain four dinoflagellate assemblages
assigned to Middle Eocene, Late Oligocene, Early Miocene and Pliocene ages respectively.
         Middle Eocene dinoflagellates have been observed in northwestern Venezuela and
include several species of the chorate genera Cordosphaeridium, Glaphyrocysta,
Homotryblium, and the proximate taxa Batiacasphaera compta, Cribroperidinium
tenuitabulatum, and Lejeunecysta spp. This assemblage is concurrent with the Middle Eocene
nannofossils Reticulofenestra reticulata and Chiasmolithus solitus, as well as the terrestrial
taxa Bombacidites bellus, Echiperiporites estelae and Spinozonocolpites echinatus.
         Late Oligocene to Pliocene dinoflagellates have been observed in strata from eastern
Venezuela and the southern part of the Gulf of Mexico. The Oligocene to Miocene taxa
include several species of Homotryblium, Polysphaeridium, together with Cribroperidinium
tenuitabulatum and Tuberculodinium vancampoe. The Miocene taxa include Diphyes
latisuculum, Spiniferites mirabilis and Hytrichokolpoma truncata, while Pliocene taxa include
several species of Spiniferites, together with Multispinula quanta, Votadinium calvum and
Hystrichosphaeropsis obscura.
         Neogene strata also include calcareous nannofossils, planktonic foraminifera and the
terrestrial palynomorphs Foveotriletes ornatus, Crassoretitriletes vanraadshoveni,
Kuylipsorites waterbolki, Magnastriatites grandiosus and Polypodiidites usmensis.
         These Middle Eocene to Pliocene fossil dinoflagellates from around the Caribbean
basin help to reconstruct the geologic development of the area, particularly tracing the
eastward movement of the Caribbean plate, separating the North and South American plates.
HIGH RESOLUTION PALYNOLOGY OF THE TARBERT
FORMATION (BRENT GROUP, MIDDLE JURASSIC) OF THE
NORTH VIKING GRABEN, UKCS

N. HOGG
Shell UK Exploration & Production, 1 Altens Farm Road, Nigg, Aberdeen AB12 3FY, UK
P. SIXSMITH
Imperial College of Science, Technology & Medicine, Prince Consort Road, London SW7 2BP,
UK
D.A. BAILEY, H. BAKRI
BioStrat Ltd, Chapelstone Cottages, Fishthwaite Lane, Backbarrow, Ulverston, Cumbria LA12
8PY, UK

The Tarbert Formation, a shallow-marine sandstone that forms the uppermost unit of the
Brent Group in the North Viking Graben, UKCS, has regionally extensive and mappable basal
and upper surfaces but displays extremely variable thickness variations. Detailed
sedimentological mapping has revealed a wide range of depositional facies with complex
interrelationships. A complimentary, high resolution palynology sampling program has
revealed a detailed, previously unattained biostratigraphy, elucidating both chronostratigraphic
and depositional facies controls and allowing the existing biozonal scheme to be updated and
applied in a predictive manner to subsequent analyses of the Formation.
PALYNOFACIES AND STRATIGRAPHY OF THE CYCLIC
DEPOSITS OF THE UPPER RHAETIAN KOESSEN BEDS
(NORTHERN CALCAREOUS ALPS, AUSTRIA)
B. HOLSTEIN
Geological & Palaeontological Institute, Johann-Wolfgang-Goethe University,
Senckenberganlage 32-34, D-60054 Frankfurt am Main, Germany
S. FEIST-BURKHARDT
Department of Palaeontology, The Natural History Museum, Cromwell Road, London, SW7
5BD, England, UK
H. HüßER
Geological & Palaeontological Institute, Johann-Wolfgang-Goethe University,
Senckenberganlage 32-34, D-60054 Frankfurt am Main, Germany
V. WILDE
Forschungsinstitut Senckenberg, Palaeobotany Division, Senckenberganlage 25, D-60325
Frankfurt am Main, Germany
A.E. GÖTZ
Institute of Applied Geosciences, Darmstadt University of Technology, Schnittspahnstrasse 9,
D-64287 Darmstadt, Germany

The Koessen Beds consist of an alternation of more or less calcareous marls and limestones,
which show well-developed transgressive-regressive cycles. These cycles show significant
changes of the palynofacies composition. Most samples yielded rich palynological residues
including diverse and well-preserved palynomorph assemblages of pollen, spores,
dinoflagellate cysts and acritarchs. These assemblages show a typical Rhaetian microflora,
including some stratigraphical important pollen, spores and dinoflagellate cysts (Rhaetipollis
germanicus, Corollina torosus, Granuloperculatipollis rudis, Riccisporites tuberculatus,
Cunaetosporites      rhaeticus,   Concavisporites    sp.,    Comparodinium       koessenium,
Rhaetogonyaulax rhaetica).
         The pollen/spores assemblages change in their quantitative and qualitative
composition and allow a correlation with the palynological zones suggested by other authors
(Morbey 1975, Achilles 1981).
         The uppermost part of the Eiberg section shows a gradual disappearance of all
significant Rhaetian taxa, which may allow to allocate the position of the Rhaeto-Liassic
boundary.
BIOECOSTRATIGRAPHY OF THE APTIAN SHU’AIBA
FORMATION OF SAUDI ARABIA

G.W. HUGHES
Saudi Aramco, R-3052, Geological technical Services Division, Dhahran 31311, Saudi Arabia

The Aptian Shu'aiba Formation is a major carbonate reservoir in the Shaybah Field of Saudi
Arabia, but lack of exposures within Saudi Arabia has forced the subsurface data to be fully
exploited for use in determining the depositional environment of the reservoir rocks and
associated lithofacies. Semi-quantitative macropalaeontological and micropalaeontological
analysis has revealed significant lateral and vertical variations that provide valuable indicators
for events possibly related to distribution of hydrocarbon reservoir facies and subsequent
reservoir architecture.
         Biofacies characteristics enable the formation to be conveniently divided into three
general layers, of which the middle layer displays the most intensive lateral and vertical
differentiation. This polycyclic layer consists of a cyclic succession of deep marine, planktonic
foraminiferal-bearing (Hedbergella delrioensis) beds that shoal upwards into calcareous algal
(Lithocodium aggregatum) and platy coral beds. This biofacies also includes the benthonic
foraminiferal species Palorbitolina lenticularis (low morphotype), Debarina hahounerensis,
Lenticulina spp., Nodosaria spp., Praechrysalidina infracretacea and Choffatella decipiens.
The `middle layer` is characterised by considerable variations in the biofacies of which rudists
are well represented. Colonisation of local submarine highs by rudists resulted in
differentiation of the basal middle layer into lagoon, rudist bank and slope environments, each
of which is characterised by a unique biofacies. The rudist assemblages are spatially clustered
to form a network of banks, and display an orderly species distribution.
         The upper layer is dominated by deep lagoonal conditions in which foraminiferal
diversity is typically high. Species include Praechrysalidina infracretacea, Debarina
hahounerensis, Vercorsella arenata, textularids and miliolids. Within the lagoon, the dasyclad
alga Hensonella / Salpingoporella dinarica is well represented. On the outer flanks of the
banks, this species is replaced by Coptocampylodon lineolatus. The upper layer contains
localised layers or pods of grey, non-calcareous, pyritic clay that may be related to karst-fill
that took place during the phase of emergence at the top of the Shu'aiba Formation.
THE STRATIGRAPHIC SIGNIFICANCE OF MICROBIOFACIES
TO SELECTED SAUDI ARABIAN RESERVOIRS

G.W. HUGHES
Saudi Aramco, R-3052, Geological technical Services Division, Dhahran 31311, Saudi Arabia

Conventional micropalaeontological biostratigraphy, using established age-indicator species,
cannot be applied to the current need for carbonate intra-reservoir correlative events. The
need for a tool to detect cryptic cyclic events for verification of the cycle hierarchy provided by
sedimentological observations can only be achieved by fully understanding the
palaeoenvironmental significance of benthonic foraminifera and associated microfossils.
         With the exception of the Miocene Wadi Waqb reservoir, where the
palaeoenvironmental preferences of species can readily be related to extant forms, such
preferences of warm, generally shallow marine Permian to Cretaceous benthonic foraminifera
are poorly investigated and generally undocumented.
         During routine, semi-quantitative micropalaeontological analysis of thin sections from
closely spaced core plug samples, trends have emerged within displays of species stacking
patterns. Such trends typically display a concentration of certain species at the base of an
event that are gradually replaced by different species towards the end of the event. Such
repetitive events are directly linked to environmental variations, the most obvious of which is
water depth, and the various associated environmental factors (hydraulic energy, light
penetration, food availability, turbidity, and salinity etc. etc.).
         When such events are calibrated with core-based sedimentological observations,
increase confidence is gained in the recognition of certain species that prefer deeper marine
conditions to those associated with the gradational steps of shallowing. The outcome of this
integration is the application of such bioevents to suggest difference in intensity of the various
sea level fluctuations, leading to a hierarchy of major, minor and subsidiary depositional
cycles. By heeding the presence of reworked shallow marine events, it is a simple step to
assign such biofacies to the lowstand, transgressive and highstand components of sea-level
cycles of all orders.
         The sediments associated with such cycles may then be better explained within
hierarchical packages that offer themselves for sequence stratigraphic interpretation and
reservoir characterization.
         The six examples here displayed offer a pioneering contribution to the
palaeoenvironmental interpretation of Permian to Miocene species for which no previous
interpretation was available. The bioevents assist in identifying depositional ―pulses‖ of the
carbonate rock record that can be calibrated with sedimentology or by revealing cryptic cycles
in carbonates where such cycles are less obvious.
QUANTITATIVE BIOSTRATIGRAPHY FOR THE PALEOGENE
OF THE LLANOS FOOTHILLS, COLOMBIA: IMPROVING
PALYNOLOGICAL RESOLUTION IN OIL EXPLORATION

C.A. JARAMILLO, F. MUNOZ, M. COGOLLO, FELIPE DE LA PARRA
Biostratigraphy team, Instituto Colombiano del Petroleo-Ecopetrol, AA 4185, Bucaramanga,
Colombia

Oil exploration in Colombia traditionally has taken place in areas with relatively few structural
complexities. But in the last decade, exploration has moved to regions characterized by high
structural deformation, poor seismic resolution, and many stratigraphic problems, such as the
eastern foothills of the Eastern Cordillera. In this region, the major reservoirs are placed in
Paleogene sequences, mostly continental rocks, where palynomorphs usually are the only
fossil group used. Thus, palynology has become a relevant tool in controlling the stratigraphic
position of a well during drilling, in testing diverse seismic and structural interpretations, and in
correlating to understand reservoir continuity. However, palynological zonations currently
used for the area do not offer the resolution needed and asked for by explorationists.
          Here, we have developed a high-resolution biostratigraphy for the Paleogene making
use of quantitative and semi-quantitative techniques such as RASC and Graphic Correlation.
We have used more than 20 sections with palynological information from outcrops, well cores,
and well ditch cuttings. Based on the biostratigraphic model produced by the quantitative
analysis, we reinterpret a recently drilled well in the Llanos foothills upon which several
previous interpretations have been made. The results offer a better understanding of the
stratigraphy of the well and allow us to make better predictions of the potential reservoir in the
area.
FOSSIL INSECT PALYNIVORY AND POLLINATION: ROLE OF
PLANT DAMAGE, COPROLITES AND GUT CONTENTS

C.C. LABANDEIRA
Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC
20560, USA; Entomology, University of Maryland, College Park, MD 20742, USA

The fossil record of vascular plant and insect associations contain five types of data that
indicate insect consumption of spores, prepollen, and pollen (palynivory) and also address the
origin of pollination mutualisms. These types of evidence are, starting from the plant end and
containing to the insect end: (1) entomophilous plant reproductive features, (2) insect damage
of plant reproductive tissues, (3) matrix dispersed coprolites, (4) insect gut contents, and (5)
insect mouthpart and ovipositor structure. Of these, the middle three represent direct effects
by insects of plant tissue consumption and provide a significant fossil record documenting the
associations between palynivorous insects and vascular plants from the earliest land
ecosystems to the recent. Accordingly, four distinctive assemblages of vascular
plant/palynivore associations characterize the terrestrial fossil record.
         The first assemblage occurs from latest Silurian to Middle Devonian and represents
basal vascular plant hosts whose animal associates are unknown, but probably were insects
or possibly other terrestrial arthropods. The second assemblage is documented from the
Middle Pennsylvanian to the Late Permian and represents pteridiphytes and basal seed plants
associated with palaeodictyopteroid, hemipteroid, and basal neopteran insects. Plants whose
miospores were consumed include marattialean ferns, cordaites, and medullosan and
glossopterid pteridosperms, and early gnetophytes, and includes damage to pteridosperm
prepollen organs. Interacting insect representatives were members of the
palaeodictyopterans, hypoperlids, psocopterans, grylloblattodeans, and possibly orthopterans,
and probably were attracted to sugary fluid rewards such as pollination drops, nectaries on
vegetative tissues, and honeydew. The third assemblage originated during the Middle Triassic
to mid-Cretaceous, but has persisted to the present. Interacting plants include bennettitaleans;
cycads; voltzialean, pinacean, and cheirolepidaceous conifers; and advanced gnetaleans.
Associated palynivorous or seed-predating insects are prophalangopsid grasshoppers, and
more basal lineages of holometabolous insects, such as nemestrinid flies, xyelid sawflies, and
nemonychid weevils. Fluid sugar rewards were provided by the pollination drop mechanism
and extrastrobilar nectaries. The fourth assemblage is found from the Early Cretaceous to the
present, and consists of angiosperms whose associates are predominantly thrips and more
derived lineages of holometabolous insects, of which the predominant sugar fluid reward is
floral nectaries.
         Hypotheses regarding the origin of pollination have overwhelmingly focused on the
phylogenies of extant plant and insect groups, without consideration of an illuminating and
relevant fossil record. Importantly, the fossil record documents four assemblages of
plant/palynivore associations, of which the first two are extinct, most of the third is gone, and
the fourth overwhelmingly dominates the extant biota. Consideration of plant damage,
coprolites, and gut contents in the preangiospermous fossil record can provide a crucial
perspective for understanding the formative processes and events characterizing the history of
pollinivory and the origin of pollination.
PALYNOLOGICAL ANALYSIS OF A 2,000 YEAR-OLD BAT-
GUANO DEPOSIT IN WALES (UK)

S.A.G. LEROY
Department of Geography and Earth Sciences, Brunel University, Uxbridge UB8 3PH, UK
M.J. SIMMS
Department of Geology, Ulster Museum, Botanic Gardens, Belfast BT9 5AB, N. Ireland, UK

The karst system is very well developed in Wales (UK) and its extension has only been
recently explored and mapped. Ogof Draenen, near Blaenavon in southeast Wales, is the
most recent major cave discovery (1994) with already > 70 km of passages across a vertical
range of 148 m.
         With the exception of a small chamber, Siambre Ddu, which lies directly above the
main Ogof Draenen system and which is an important roost for lesser Horseshoe
(Rhinolophus hipposideros) and a few Greater Horseshoe (Rhinolophus ferruequinum) bats,
very few bats have been seen in the main system. Hence, the guano accumulations found in
parts of the Ogof Draenen system are unexpectedly large. The heaps, several sqm and > 0.5
m thick, represent volumes unmatched by any other cave system in the British Isles.
         A guano sample from Ogof Draenen was radiocarbon dated at 2000 yr ago, placing
the sample in the Romano-British period.
         Pollen analysis was applied to it as well as nine other samples distributed over the
cave at various distances from the presumed entrance and also through the heaps
themselves. Comparisons were done to a moss pollster and a mud sample from the area and
to two modern guanos from Agen Allwedd cave (5 km to the north-west) which currently is one
of the largest active roosts for Lesser Horseshoe bats in Britain and lies close to their present
northern limit in Europe.
         The main results are:
         That most of the Ogof Draenen guano is probably of the same age.
         That the modern samples are clearly characterised by the presence of planted trees,
invasive plants, and grassland and heathland (vs the fossil samples which reflect a closed
forest).
         That insect-pollinated plants such as Ilex, Acer, Hedera and Impatiens glandulifera
are over–represented in the guano samples.
         That various ways of incorporation of the pollen grains to the guano act jointly. Insect
eating and grooming by the bat as well as direct air transport by draughts created by
temperature difference between the cave and outside take place.
GONYAULAX vs. SPINIFERITES

J.M. LEWIS
Phytosciences Research Group, School of Biosciences, University of Westminster, London,
W1W 6UW, UK
M. ELLEGAARD
Department of Phycology, Botanical institute, University of Copenhagen, Øster Farimsgade
2D, DK-1353 Copenhagen K Denmark
A. ROCHON
Geological Survey of Canada (Atlantic), PO Box 1006, Dartmouth, Nova Scotia, B2Y 4A2,
Canada
I.C. HARDING
School of Earth and Ocean Sciences, Southampton Oceanography Centre, University of
Southampton, European Way, Southampton, SO14 3ZH, UK
N. DAUBJERG
Department of Phycology, Botanical institute, University of Copenhagen, Øster Farimsgade
2D, DK-1353 Copenhagen K Denmark
R.A. FENSOME
Geological Survey of Canada (Atlantic), PO Box 1006, Dartmouth, Nova Scotia, B2Y 4A2,
Canada
F.J.R. TAYLOR
Department of Oceanography, University of British Columbia, Vancouver, B.C., V6T 1Z4,
Canada

The pioneering incubation work of Wall and Dale, some thirty years ago, linked the planktonic
Gonyaulax spinifera group to a number of fossil cyst-based genera (Spiniferites,
Impagidinium, Bitectatodinium, Nematosphaeropsis, Ataxiodinium, Pentadinium, and
Tectatodinium). Thus began the Spiniferites enigma whereby apparently one motile species
could produce cysts referable to several genera. The question has remained whether cyst-
based taxa were overclassified or whether taxonomic distinction of motile taxa was
insufficient. Over 2000 individual isolations of cysts from Spiniferites and related cyst genera
have led to the establishment of cultures grown from single cysts of the following cyst-based
species: Bitectatodinium tepikiense; Spiniferites elongatus; S. membranaceus; S. ramosus,
and a previously undescribed Spiniferites species. According to the ICBN, genera based on
extant forms have priority over genera based on fossil forms; therefore, these cyst-based
species are referable to Gonyaulax digitalis, G. elongata, G. membranacea, G. spinifera and
G. baltica respectively. (However, the ICBN also allows for retention of the cyst names as
morphotaxa.) Cysts produced in culture showed a wide range of intraspecific morphological
variation. This indicates that cyst-based taxa may be overclassified, but variation is largely
along a recognisable continuum; for example, from cysts with no spines to cysts with long
spines. Superficially, morphology of motile cells from different cyst species is similar,
however, detailed examination (by SEM) reveals each to be distinct, leading to the conclusion
that motile stages were previously underclassified. Confirmation of this interpretation is
supplied by molecular data. Approximately 1500 base pairs of nuclear-encoded large sub-unit
rDNA were determined for G. baltica, G. digitalis, G. elongata, G. membranacea and G.
spinifera and the level of sequence variation compared with other Gonyaulacales. This work
showed that the level of genetic variation within cysts recognised as distinct Spiniferites
species is high and merits species separation.
DINOFLAGELLATE CYST BIOSTRATIGRAPHY IN THE
MIOCENE OF NW GERMANY IN CONTINUOUS CORED WELLS
J.J. LUND
RWE-DEA Laboratory, D-29323 Wietze, Germany

          The boreholes Nieder Ochtenhausen and Wursterheide, located 46km from each
other in NW Germany, yield the thickest Middle to Upper Miocene sections ever cored in or
near the North Sea. They were drilled by the Geological Survey of Lower Saxony for a
multidiscipline investigation. A major advantage of such sections, compared to the small
isolate outcrops available in NW Germany, is that the succession of microflora is clear.
          Dinoflagellates were analysed from 84 samples of Nieder Ochtenhausen representing
99m of Miocene section and the occurrences of 86 taxa presented on a semi-quantitative
chart recently published (Strauss et al., 2001). Based on these data and dinoflagellate cyst
ranges in the Danish Gram borehole with Lower Miocene a new zonation scheme was
proposed. It is an extension of J. Powell‘s 1992 scheme which had to be adjusted to
incorporate new index taxa (Coustadinium aubryae ssp. gonoperforata, Palaeocystodinium
miocenicum, Cannosphaeropsis passio) and to take into consideration new information on the
first stratigraphic appearance of Amiculosphaera umbracula. Cannosphaeropsis passio is an
important marker in the higher Middle Miocene dated by other means in the Groß Pampau
well. Contrary to earlier opinions, the genus Palaeocystodinium ranges into the deeper Upper
Miocene, but differentiation of species helps to distinguish Upper, Middle and Lower Miocene.
The occurrences of Hystrichosphaeropsis obscura and Selenopemphix armageddonensis
overlap in the higher Upper Miocene indicating a stratigraphically more complete sedimentary
succession than from eastern North America.
          55 samples from Wursterheide well, representing 185m higher Lower Miocene to
Upper Miocene were analysed by C. Heilmann-Clausen, and a correlation with Nieder
Ochtenhausen was published (Lund & Heilmann-Clausen, 2001). The correlation is
straightforward and unproblematic in the higher Lower to Middle Miocene but complicated in
the Upper Miocene where Achomosphaera ramulifera is recognised as a biostratigraphically
important species. The correlation reveals that some dinoflagellate events are missing at a
hiatus at ca. 261m in Wursterheide. The missing section corresponds to the interval 90-110m
in Nieder Ochtenhausen. The hiatus is probably due to a sea level drop at, or near the
boundary between the Middle and the Upper Miocene.
          The upper boundary of the Miocene is problematic in both discussed wells. H.
obscura is present but the large and characteristic Impagidinium “densiverrucosum”, which
occurs in the microfaunally dated Pliocen-Miocene transition of the Ems Area and is tentatively
used to mark the top of the Miocene in the southern North Sea, could not be found.
ENVIRONMENTAL INFORMATION FROM THE PALYNOLOGY
OF BAT GUANO
L.J. MAHER, Jr
Department of Geology and Geophysics, University of Wisconsin, 1215 W. Dayton Street,
Madison, WI 53706 USA

Bat droppings accumulate in caves, and the resultant guano contains a stratigraphic record of
the environment analogous to the record from lake sediment and peat. The bats forage at
night for insects over a particular area, and they return to the cave during the day to sleep and
care for their young. They attach themselves to suitable perch areas of the cave ceiling, and
their excrement accumulates on the floor below. Flying requires a lot of energy, and this
requires the bats of temperate regions to consume large numbers of night-flying insects. In
some situations the guano can reach a depth of meters in hundreds to thousands of years,
and it has a valuable chronostratigraphy. The bat scats occur as small pellets that individually
represent the non-digestible portion of the animal's diet in the preceding day; hence the diet
provides information about the time of the year the feeding occurred. Bat guano contains,
among other things, insect fragments, hair, pollen, and some mineral matter. Night-flying
insects do not normally visit flowers for the pollen; many species do not eat during the flying
phase of their life cycle, and those that do generally are nectar feeders. Although the insects
are not after the pollen, they do fly through a pollen-laden environment, and the pollen and
dust adheres to their bodies. The insects essentially act as living traps for airborne debris.
The bats also are furry pollen traps; during grooming they ingest pollen and dust enmeshed in
their fur, and this also is excreted. Study of the pollen in an individual scat contains a record
of the atmospheric pollen during a single day in the past. Pollen from multiple scats can
provide a record of a season. This kind of detail is hardly ever available from lake sediment.
          Chemical analysis of individual bat scats in a time series can provide a record of the
region's changing environment caused by agriculture, industry, volcanic dust, and a host of
other details that depend only on the cleverness of the researcher. Careful carbon-14 analysis
can isolate times when bats did not use the cave, and that negative evidence can also be
used to interpret past conditions. If the types of insect in the guano change over time, that
may also provide evidence of changing climate.
          Tom Aley, owner of the Ozark Underground Laboratory, Protem, Missouri, USA,
allowed me to collect guano samples for an exploratory study. Tumbling Creek Cave contains
a maternal colony of the Grey Bat (Myotis grisescens) that occupies the cave for a short time
                                                                                              14
each year. Scats collected from the base of a 75-cm thick cone of guano yielded an AMS C
date of 2810 ± 40 (CAMS 85667). The fecal material has a crumbly structure below the
surface; it was of mahogany color (7.5 YR 2/1 to 3/2) and had no noticeable odor. The feces
contained many insect fragments, hair, and a wide assortment of pollen and spores. Guano
can be processed like normal sediment, but simple washing in a weak detergent solution
followed by acetolysis appears adequate. Normal sediment coring devices compress the
guano; this can be avoided by using a modified "Russian" peat sampler or by freezing the
guano to a dry-ice-cooled probe.
ARTHUR RAISTRICK: BRITAIN’S PREMIER PALYNOLOGIST

J.E.A. MARSHALL
SOES, Southampton Oceanography Centre, Southampton, SO14 3ZH. UK

Arthur Raistrick undertook pioneering palynological research at the very start of the systematic
study of fossil pollen and spores. At that time his research interests were in both glaciation
and coal geology. His contribution was to adopt the method of pollen profiling in peat to coal
seams. Firstly he developed a robust method for the routine extraction of palynomorphs from
coal. He then devised a binomial letter/number system to name the palynomorphs. Initially his
approach was to profile the coal seams followed by characterizing the entire seam by use of a
channel sample. This proved that the same coal seam had the same palynological content
and was different from other coal seams. He tested these methods on a number of coal
seams at a large number of collieries in northern England. This gave pre-Quaternary
palynology both a scientific basis and an immediate commercial application. With onset of the
WWII he withdrew from palynology never to return.
PALYNOLOGY AND MATURITY STUDIES IN A
STRUCTURALLY COMPLEX TERRAIN: THE DEVONIAN OF
BOLIVIA

J.E.A. MARSHALL
SOES, Southampton Oceanography Centre, Southampton, SO14 3ZH, UK
A. RACEY, P. ELLIS, M. WAKEFIELD
BG-Group, 100 Thames Valley Park Drive, Reading, Berkshire RG6 1PT, UK
K. HETFIELD
Department of Geology, Trinity College, Dublin 2, Ireland
C. HARVEY
Ichron Ltd, Northwich, Cheshire, CW9 7TN

A significant proportion of the hydrocarbons in Bolivia are found in the sub-Andean zone. This
is a fold and thrust belt immediately east of the main Andean range. The local Devonian
stratigraphy comprises from top to bottom; the Los Monos, Huamampampa, Icla and Santa
Rosa formations. The sandstone dominated Huamampampa and Santa Rosa formations form
the main reservoir intervals. Differentiating these reservoirs in intervals where they are
commonly repeated and are complexly interthrusted with shaley/silty facies of the Los Monos
and Icla has to date been unsatisfactory being mainly based on log response and existing
structural models. These difficulties are compounded by the lack of definition in the seismic
exacerbated by the presence of low angle thrusts.
          The wells are deep and many drilling problems have been encountered. Recovery of
either core or full log suites has often been difficult. The palynomorph assemblages are
generally of low diversity and are frequently thermally very mature. However, successful field
development still requires the development of integrated structural and stratigraphic models
based on these wells.
          The key to developing the stratigraphic framework from which the model is developed
model is the recognition of a number of discrete palynological events. These are pulses of
distinctive acritarchs typically in high abundance but low diversity. This permits a number of
correlative levels to be recognised. These frequently show that there is a previously
unrecognised structural repetition of the succession. In order to detect the location of these,
generally low angle, faults a combination of dip-meter and thermal maturity measurements are
combined with log interpretation. The thermal maturity measurements are made using a
selection of materials. The preferred being chitinozoans, which are easily recognised in
polished section. Other organic matter measured includes sporinite, vitrinite and cutinite. The
low angle faults are detected by the sudden jumps in thermal maturity often with short sections
of reversed gradient. Non-organic means of measuring maturity specifically through the study
of clay minerals has also been undertaken and calibrated against chitinozoan, cutinite and
vitrinite reflectivity data. These integrated palynological and thermal maturity methods enable
the stratigraphy in the wells to be determined which then constrains the structure as
interpreted from the seismic lines.
PALYNOLOGICAL EVIDENCE FOR CRUSTAL SUBSIDENCE
DURING LATE HOLOCENE EARTHQUAKES IN COASTAL
BRITISH COLUMBIA, CANADA

R.W. MATHEWES, J.F. HUGHES
Department of Biological Sciences, Simon Fraser University, Burnaby, B.C., V5A 1S6 CAN

Various palaeoecological techniques are being used to identify past earthquakes on the
Pacific Coast of North America, and reconstruct their frequency. Tree rings, foraminifera, and
diatoms are all being used to estimate the timing and effect of coseismic changes within the
Cascadia subduction zone, which experiences occasional great (> magnitude 8) seismic
events, as well as frequent smaller quakes. The analysis of pollen from coastal marsh
sediments is shown to be a useful technique for estimating the amount of crustal subsidence
associated with major earthquakes. This information is critical for checking the estimates
using other techniques, and ultimately for building better geophysical models of crustal strain
accumulation and release.
         Palynological studies have identified past coseismic subsidence in buried marsh soils
near Vancouver, B.C., a large metropolitan area on the Fraser River Delta. Rapid burial of
coastal soils due to subsidence is accompanied here by evidence of liquefaction and drowned
trees.
         The best data for estimating the actual amount of coseismic subsidence comes from
the Tofino area of western Vancouver Island, where the most recent subduction zone
earthquake occurred in A.D. 1700, leaving a tsunami sand sheet as well as buried soils. The
sand is overlain by intertidal mud which grades up into the present-day marsh. Elevational
studies of modern marsh plant communities were combined with analyses of pollen in surface
samples and buried sediments. Pollen analysis shows that a high marsh, with pollen of
Poaceae, Potentilla, Achillea type, and Angelica type existed at the head of English Cove prior
to the 1700 quake. This assemblage was suddenly replaced by low marsh vegetation with
Cyperaceae, Chenopodiaceae and Triglochin. Comparison of these buried assemblages with
modern analogue elevations suggests that the amount of subsidence was approximately 0.6
m, corresponding well to estimates using fossil foraminifera from the same area.
FOSSIL POLLEN GRAINS IN THE DIGESTA OF MICE AND
MASTODONS

J.H. McANDREWS
Departments of Botany and Geology, University of Toronto, 25 Willcocks St., Toronto ON M5S
3B2 Canada

Two contrasting sites with fossil digesta (gut contents and dung) illustrate herbivore diets.
                            o          o
January Cave, Alberta (50 11' N, ll4 31' W, 2040 m asl), is a rock shelter surrounded by
Rocky Mountain subalpine forest of Pinus contorta; it lies 400 m below alpine tundra. The
landscape was not glaciated. Unlike the modern pollen rain, the dry cave earth of weathered
limestone had <7% tree pollen and most pollen was of entomophilous alpine tundra plants
such as Claytonia, Phlox, Polemonium, Polygonum viviparum and Saussurea.
Contemporaneous bones, dominated by the rodents Peromyscus and Spermophilus but also
including small carnivores, date 33,000 to 23,000 yr B. P. Most pollen was transported to the
cave in rodent digesta by birds of prey (mostly owls) and small carnivores.
         The Hiscock Site, New York (43 05‘ N, 78 05‘ W, 189 m asl), in the St. Lawrence
Lowland is a 0.8 ha Typha-dominated terrigenous peatland surrounded by farm fields.
Following deglaciation 12,500 yrs B. P., a salt-water pond attracted vertebrates and a
mastodon bone-rich Fibrous Gravelly Clay layer dating 11,450 to 10,200 yr B. P. was
deposited. It contains a Picea glauca-dominated tree pollen assemblage that indicates spruce
woodland. There is also super-abundant pollen of non-arboreal upland plants – Gramineae,
Cyperaceae, Compositae and Rosaceae (probably Potentilla fruticosa), together with
occasional pollen of entomophilous Lonicera, Cornus, Ericaceae, Elaeagnus, Salix,
Shepherdia canadensis, Ranunculus, Epilobium, Galium, Campanula, Sanguisorba and
Polygonum bistorta and anemophilous Thalictrum, Chenopodiineae, Artemisia, Plantago major
type, Selaginella selaginoides, Botrychium, Lycopodium annotinum and fungal spores. This
palynomorph assemblage, together with barkless spruce twigs, spruce needle fragments and
clay testifies that the layer is digesta from mastodon, who browsed on spruce trees and
shrubs, grazed on herbs and ate soil.
MICROPALEONTOLOGICAL INSIGHTS INTO PACIFIC
PALEOPRODUCTIVITY: IMPLICATIONS FOR LATE CENOZOIC
GLOBAL CLIMATE CHANGE

F.M.G. McCARTHY
Department of Earth Sciences, Brock University, St. Catharines, ON CANADA L2S 3A1
R. OHLENSCHLAGER PEDERSEN
Schlumberger, Kokstadveien 34, 5257 Kokstad NORWAY
A.M. KRUEGER, J. PAUL, K.D. JAMIESON, M.L. LITTLE
Department of Earth Sciences, Brock University, St. Catharines, ON CANADA L2S 3A1

Calcareous sediments do not normally accumulate in the extra-equatorial abyssal Pacific
despite the abundance of calcareous plankton in surface waters, because the carbonate
compensation depth (CCD) is shallower than the seafloor. Calcareous sediments (>5%
CaCO3) have been identified well below the CCD in the mid latitude North Pacific: five
intervals of anomalous carbonate preservation were dated ~6.3, 5.1, 3.6, 2.5 and 0.7 Ma at
                                             o         o
ODP Site 881 (~5530 m water depth, 47 6'N, 161 29'E), and four calcareous intervals were
                                                                              o        o
dated ~3.6, 2.5, 1.65 and 0.9 Ma at Site 1179 (~5565 m water depth, 41 4'N, 159 58'E'). This
extends the cycles of carbonate preservation in the abyssal Pacific Ocean beyond the
equatorial latitudes where they have long been recognised. Because the abyssal Pacific
                     o       o
Ocean between 50 N & 50 S comprises ~1/3 of the Earth‘s surface area, the amount of CO 2
sequestered in these sediments may have driven the global cooling documented for these
times in geologic history.
         Although carbonate preservation cycles appear to be linked with global climate
change, their cause is not yet fully understood and remains one of the more intriguing
paleoceanographic problems. Palynological data show that the intervals of carbonate
preservation in the mid-latitude western Pacific were associated with enhanced terrigenous
flux (high concentrations of pollen and embryophyte spores) and sea surface productivity (high
concentrations of the cysts of dinoflagellates). Primary productivity may have been enhanced
during times of increasing continental aridity in Asia, when dust (including limiting nutrients like
iron) was transported offshore by westerly winds. We suggest that the greater flux of particles
to the seafloor, including the remains of calcareous plankton, depressed the CCD and
increased burial rates, allowing carbonates to accumulate (including well-preserved planktonic
foraminiferal tests in some samples). Cysts of heterotrophic dinoflagellates are abundant in
samples with planktonic foraminifera but not in those intervals with recrystallised calcite. This
is consistent with the theory of greater flux resulting in rapid burial and enhanced preservation,
because the protoperidinioid cysts of heterotrophic dinoflagellates are much more susceptible
to degradation than the gonyaulacoid cysts of autotrophic dinoflagellates. Siliceous microfossil
assemblages (diatoms, silicoflagellates and radiolarians) show no correlation with the
anomalous CaCO3 peaks, suggesting the anomalous preservation did not result from changes
in surface water masses or currents (e.g. Kuroshio Current).
PALYNOLOGICAL RECORD OF MIOCENE SEQUENCES IN
THE U.S. MIDDLE ATLANTIC COASTAL PLAIN: INITIAL
RESULTS FROM THE BETHANY BEACH BOREHOLE,
DELAWARE

P.P. McLaughlin, Jr
Delaware Geological Survey, University of Delaware, Newark, DE 19711, USA
K.G. MILLER
Dept of Geological Sciences, Rutgers University, Piscataway, NJ 08854, USA
R.N. BENSON
Delaware Geological Survey, University of Delaware, Newark, DE 19711, USA
J.V. BROWNING
Dept of Geological Sciences, Rutgers University, Piscataway, NJ 08854, USA

The Bethany Beach borehole provides a nearly continuous record of the Miocene of the
Delaware Coastal Plain. This 1470-ft-deep, continuously cored hole penetrated Miocene
sequences near their maximum regional thickness, yielding new insights on the influence of
sea level, tectonics, and sediment supply on the depositional history of the area.
         The Miocene section is predominantly a stack of highstand systems tracts composed
of shallow- and marginal-marine clastic sediments. Sequence boundaries are recognized
where significant flooding events coincide with unconformities and have been dated using Sr-
isotope biostratigraphy. The Miocene succession passes upward from glauconitic sands and
silts in the lower part of the lower Miocene, to four thick (100-270 ft) shallow-marine
sequences of silt and sand in the upper part of the lower Miocene, to three thinner (50-100 ft)
sand- and shell-rich nearshore sequences that comprise most of the middle Miocene. These
are overlain by two finer-grained, glauconitic shelf sequences in the upper part of the middle
Miocene. The overlying upper Miocene (to possibly Pliocene) section is a coarsening- and
shoaling-upward succession of shallow marine clastics, capped by interbedded sands and
muds deposited in beach and estuarine environments.
         Palynological analysis reveals a Miocene flora dominated by Quercus, with common
Carya and Pinus, and several ―exotic‖ taxa that do not presently live in the area. The lower
Miocene assemblages are mostly composed of temperate and warm-temperate arboreal
forms, but have common subtropical to tropical exotics, including common Engelhardia-type
pollen and scattered Podocarpus. Middle Miocene assemblages are similar but have fewer
exotics; Engelhardia-type pollen is most common but generally decreases upward, and
Pterocarya, Podocarpus, and Symplocos are present. A shift to fewer Pinus and more non-
arboreal pollen (Compositae, Gramineae, and Umbelliferae) occurs in the upper part of the
middle Miocene. The character of the assemblage continues to change in the upper Miocene
(to possibly Pliocene) section, with more abundant Carya, a decline of non-arboreal types, and
a gradual increase in Liquidambar. Exotics are consistent but less abundant, with rare
Pterocarya and scattered occurrences of Engelhardia-type pollen, Podocarpus, and cf.
Dacrydium.
         Overall, the palynological data reflect subtropically influenced warm-temperate
aboreal environments in the Miocene of this area, but with a decrease in subtropical
influences through the middle and late Miocene. Dinoflagellates are present, reflecting marine
deposition at this site, but are less abundant and diverse upward. The increase of non-
arboreal pollen in the later middle Miocene may record a drier period, and the late Miocene
increase in Carya and Liquidambar may reflect subsequent wetter conditions.
CURRENTLY ACHIEVED RESOLUTION IN
BIOCHRONOSTRATIGRAPHY AND SEQUENCE
STRATIGRAPHY BASED ON DINOFLAGELLATE CYSTS AND
SPORE-POLLEN IN THE PETROLIFEROUS BASINS OF INDIA
N.C. MEHROTRA, H.S. ASWAL, KAMLA SINGH, D.S.N. RAJU
KDMIPE, ONGC Ltd., 9 Kaulagarh Road, Dehra Dun –248 195 (India)

The paper presents a review of dinoflagellate and spore–pollen studies in various commercial
hydrocarbon producing basins of India and the resolution achieved so far in
biochronostratigraphy and their application in sequence stratigraphy. In Cambay Basin five
dinoflagellate biohorizons have been identified within Ypresian and the resolution varies from
5.8 to 13.2 Ma. In Mumbai Offshore Basin twenty biohorizons have been distinguished
between Ypresian to Miocene; fine time slicing upto one million year has been achieved.
         In Cauvery Basin dinoflagellate cysts have been useful in precisely dating Cretaceous
to Early Eocene sediments and are partly tied up with planktic foraminifera. Maximum data is
available from Krishna –Godavari Basin. Seventy-nine dinoflagellate biohorizons have been
identified between Middle Triassic to Holocene with a fine time slicing from 0.5 to 1 Ma.
Standard biozonation of Triassic to Holocene sediments has been achieved. Seventy-eight
interval zones have been distinguished and tied up with foraminiferal data. In Assam Basin,
seven biochronohorizons have been distinguished between Thanetian top to Priabonian and
resolution varies from 3.3 to 17.8 Ma.
         Dinoflagellate cyst biohorizons have helped to build a high-resolution biostratigraphy
and further strengthened by available foraminiferal data. Application of terrestrial palynofossils
and dinoflagellates has been made to develop paleoenvironmental models in each of the
studied basins. Paleogeographic reconstructions in Panna Formation, Mumbai Offshore has
been done at one million year interval within Ypresian (54 to 49 Ma) based on integrated data.
         Application of dinoflagellate cysts in building sequence biostratigraphy has been made
in Krishna–Godavari Basin; a case history from Ramachandrapuram area has been cited
where ten depositional sequences have been identified between Oxfordian to Late
Maastrichtian. The data is integrated with other parameters like seismic and well logs to be
applied in exploratory analysis.
         The     importance      of    dinoflagellate    cysts  in    the     Mesozoic–Cenozoic
biochronostratigraphy of India is enhanced partly because of the absence or presence of only
rare non–diagnostic age markers like foraminifera in very shallow marine facies. On the other
hand resolution based on spore–pollen is crude but valuable in classification where
dinoflagellate cysts and other markers are absent as in case of Tripura–Cachar and Schuppen
Belt of North Eastern India. In case of Upper Assam Shelf zones of spore –pollen and
dinoflagellate cysts are tied up.
         Potential of dinoflagellate cyst studies in deep water exploration research has been
outlined.
PALYNOLOGY OF THE LOWER CRETACEOUS McMURRAY
FORMATION, ALBERTA, CANADA

D. MICHOUX
TotalFinaElf, CSTFJ, Avenue Larribau, 64000 Pau, France

The Lower Cretaceous McMurray Fm is the main reservoir of the Athabasca heavy oil
province of Alberta, western Canada. These deposits are currently being developed by two
unconventional techniques: surface mining and in situ thermal Steam Assisted Gravity
Drainage (SAGD). The definition of an accurate geological model is important for the drilling
strategy associated with SAGD. This is made especially difficult by complex lithofacies
variations. The marginal character of the Mc Murray in terms of depositional environment
results in a specific biological context, with virtual absence of nannoplankton/foraminifera, but
rich and diverse palynological assemblages. The aim of this palynological analysis was thus to
contribute to the interpretation of the depositional environment of these deposits, using field
samples collected along riverbeds in the Fort McMurray area.
         Palynological assemblages are dominated by land-derived pollen and spores. A
planktonic fraction is however always present, varying qualitatively and quantitatively. It is
subdivided into 3 categories:
         -Freshwater microplankton (including freshwater dinocysts). Well-documented
freshwater types are present. They include single-celled forms (Lecaniella, Ovoidites,
Schizosporis) as well as algal colonies (Pediastrum, Scenendismus). Several freshwater
dinoflagellate species were described from the Wealden were also recorded: Hurlandsia
rugaris, Kallosphaeridum inornatum.
         - Marine dinoflagellates. Most forms recorded within the McMurray Fm belong to well-
known Cretaceous genera and species, some described in the district of Mackenzie, Canada.
         -low salinity microplankton. Most forms included in this category are undescribed at
species level but belong to genera known to have freshwater representatives (Nyktericysta,
Balmula), described in lacustrine basins from Canada and northern China. Typical low salinity
assemblages are characterised by low diversity and low to moderate abundance. They also
occur alongside marine dinocysts in higher salinity environments, probably reflecting salinity
tolerance but also basinward transport.
         Variations in type and frequency of the main palynomorph groups allowed the
definition of 6 palynofacies. Their recognition and their succession complements the
interpretation based on sedimentological features and trace fossils, and helps ascertain the
geological model.
LATE CRETACEOUS DEPOSITIONAL ENVIRONMENTS,
NORWEGIAN SEA: APPLICATIONS OF BIOSTRATIGRAPHY,
REWORKING AND PROVENANCE STUDIES IN EXPLORATION
MAPPING

P.S. MILNER, R. CORFIELD, E.K. HANSEN, K. NYBERG
BP Norge, Godesetdalen 8, P.O.Box 197, N-4065 Stavanger, Norway
A.C. MORTON
HM Research Associates, 100 Main Street, Woodhouse Eaves, Leicestershire LE12 8RZ,
U.K.

Examples from a series of sequence-based, regional Gross Depositional Environment maps
are presented, addressing key issues on reservoir and source distribution in the Norwegian
Sea. These illustrate the applications of biostratigraphic data in sequence/depositional
environment and provenance studies, alongside new seismic and structural mapping.
         Biostratigraphy has played a key role in refining and applying the Cretaceous
sequence stratigraphic framework both in terms of correlation and the interpretation of
depositional environments. These interpretations have been integrated into an updated
understanding of the structural framework of the Norwegian sea, which includes a series of
reconstructed palaeobathymetric maps through the Cretaceous and early Tertiary. Integration
of this work has enabled the regional mapping of 8 Cretaceous sequence intervals in terms of
their Gross Depositional Environments.
         The maps highlight the challenge of understanding the interplay and changing
influences of uplift and erosion of the major sediment sources of East Greenland, Nordland
Ridge and the Norwegian margin, particularly during the Late Cretaceous. Integration of
Heavy Mineral/Provenance data with that of reworked fossil palynomorph occurrences has
significantly impacted the overall depositional model. It has also highlighted some areas where
further work is required to fully understand the nature of the depositional systems.
         Three examples illustrating gross depositional environments within specific sequence
intervals and areas are presented.
         1) The Trøndelag Platform area during deposition of the main Lange Formation
sandstones and a candidate source rock interval (Cenomanian-Middle Turonian, sequences
K62-K68.
         2) The Trøndelag Platform area during deposition of the main Lysing Formation
sandstones (Late Turonian- Middle Coniacian, sequence K72).
         3) The East Greenland/Vøring Møre Basin-Nordland Ridge area during deposition of
the Nise Formation sandstones (Campanian, sequence K80).
CONTRIBUTION OF THE PALYNOLOGY OF COPROLITES TO
THE KNOWLEDGE ON DISEASES AND THE
PHARMACOPOEIA OF PREHISTORIC MEN OF
PALEOINDIANS PEOPLE FROM PIAUSI, NORTH-EAST
BRAZIL

S.A. de MIRANDA CHAVES
Fundação Oswaldo Cruz - Escola Nacional de Saúde Pública (ENSP) - Departamento de
Endemias Samuel Pessoa, Rua Leopoldo Bulhões 1480, térreo - Manguinhos. Cep 21041-
210 Rio de Janeiro - RJ, Brasil

The attention given to the study of well-preserved coprolites collected on archaeological sites
dates to the end of the XIX and the beginning of the XXth century. Since that time
prehistorians and palynologists have been preoccupied with the beginning of agriculture and
the anthropical effects upon the environment. Our study is directed towards the coprolites
collected in sediments from the rock-shelter of Pedra Furada located in the Piaui State, North-
East, Brazil (8 50‘ 10‖ S - 42 33‘ 20‖ W). This rock - shelter presents a 5m thick filling whose
sequence contains 3 Pleistocene and 3 Holocene layers with human influence. The pollen
from these coprolites were analyzed. The results have given a very important
palaeoethnological data. Evidence emerges regarding the range of medicinal and food plants
of the prehistoric humans who inhabited the site for some 1500 years (8 500 - 7000 B.P.).
SEQUENCE BIOSTRATIGRAPHY IN THE HAIMA
SUPERGROUP, CENTRAL OMAN

S.G. MOLYNEUX
British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK
P.L. OSTERLOFF
Petroleum Development Oman, PO Box 81, Muscat 113, Sultanate of Oman
R.A. PENNEY
Reservoir Laboratories AS, P.O. Box 96, Postal Code 116, Mina Al-Fahal, Sultanate of Oman
P. SPAAK
Petroleum Development Oman, PO Box 81, Muscat 113, Sultanate of Oman

Discoveries of significant gas/condensate reserves in the Haima Supergroup of Central Oman
highlight the need to understand the stratigraphic architecture of the supergroup, to identify
stratigraphic traps and determine the relationships between reservoirs and seals.
Biostratigraphy has a role to play in determining Haima stratigraphy, but until now
biostratigraphic schemes have been imprecise, individual zones often spanning one or more
lithostratigraphic units and chronostratigraphic divisions.
         New palynological studies hold the promise of higher biostratigraphic resolution. At
their heart lies the recognition that marine flooding events in the Haima Supergroup are
characterised by unique assemblages of marine palynomorphs. In the upper Haima (Mahatta
Humaid and Safiq groups), distinct and often diverse marine palynomorph assemblages occur
in the Late Cambrian, Early Ordovician (Late Tremadoc), Middle Ordovician (Llanvirn), Late
Ordovician (separate Caradoc and Ashgill assemblages) and Early Silurian (Llandovery). The
intervening strata yield low diversity and generally sparse palynomorph assemblages that
indicate marginal marine and non-marine environments.
         Recognition of distinct marine assemblages has led to more precise correlation
between subsurface sections in the Haima Supergroup, and to a better understanding of
stratigraphic relationships, including lateral facies trends.      Furthermore, the discrete
assemblages provide data to test sequence stratigraphic models developed for the Arabian
Plate, as they should exhibit a spatial relationship to candidate maximum flooding surfaces.
Viewed in the context of sequence stratigraphy, the biostratigraphy being developed for
Central Oman may have wider application for the Arabian Plate as a whole.
MORPHOSTRATIGRAPHY – A NEW NON-TAXONOMIC
BIOSTRATIGRAPHIC TECHNIQUE APPLIED TO A
BIOTURBIDITIC DEEP SEA RESERVOIR, MAUREEN
FORMATION, FLEMING FIELD, UKCS

E. MONTEIL
Geoscience Australia, GPO Box 378, Canberra, ACT 2601, Australia

Palynology is widely used in exploration for dating and correlating. However, since key
markers may be rare or absent, it is sometimes difficult to identify sufficient bioevents to finely
correlate wells, particularly at reservoir scale. This is especially crucial to
compartmentalisation modelling and understanding production behaviour since many
reservoirs occur within a single biozone. To solve this issue a new technique called
morphostratigraphy has been successfully applied in the Maureen Formation reservoir.
         The concept of morphological character stratigraphy (morphostratigraphy) was
described by Monteil (1990), and defined as ―the study of selected unambiguous
morphological features varying in time‖. Classical biostratigraphy is based on the distribution
of taxa through time, where taxa are defined by a unique set of morphological characters.
Morphostratigraphy, however, is based simply on the distribution of morphological character
through time. Morphological characters are treated either as individual units or as two or more
characters in combination, regardless of their taxonomic affiliation.
         Application of this new technique to the Maureen reservoir proves that
morphostratigraphy provides greater biostratigraphic resolution than was achieved by the
conventional approach, significantly improving reservoir correlations. This method highlighted
a different partitioning of the reservoir, which explained production problems experienced by
BG group. The study also clearly demonstrates the applicability of morphostratigraphy to
refine correlations within deep marine turbidite settings.
CRETACEOUS-TERTIARY BOUNDARY IN THE DENVER
BASIN, COLORADO – THE MOST COMPLETE K-T BOUNDARY
SECTION KNOWN IN NONMARINE ROCKS

D.J. NICHOLS
U.S. Geological Survey, MS 939, Box 25046, Denver, CO 80225, USA
R.F. FLEMING, R.S. BARCLAY
Denver Museum of Nature & Science, Denver, CO 80205, USA
J.J. EBERLE
Canadian Museum of Nature, Ottawa, Ontario K1P 6P4, Canada
W.J. BETTERTON
U.S. Geological Survey, MS 939, Box 25046, Denver, CO 80225, USA
J.F. HICKS, K.R. JOHNSON
Denver Museum of Nature & Science, Denver, CO 80205, USA

A new Cretaceous-Tertiary (K-T) boundary locality in the Denver Basin, Colorado, is the most
complete K-T boundary section known in nonmarine rocks. The new locality—the West Bijou
Site—is established and verified by palynology and the presence of impact debris; it is within a
magnetically reversed interval (subchron C29r) that is bracketed by vertebrate fossils
(dinosaurs and mammals), Maastrichtian and Paleocene megafloras, invertebrate fossils, and
radiometrically dated ash beds in a nonmarine fluvial setting. The boundary is marked by a
tonstein-like parting within a lignite bed in the Denver Formation exposed along West Bijou
Creek about 50 km ESE of Denver.
          Palynological analysis of the West Bijou Site is based on 17 samples collected
through an interval of 182 cm; the eight most important samples are from an interval of 35 cm
centered on a 3-cm-thick, tonstein-like parting in the lignite. Assemblages from the parting and
the lignite below it include a total of eight Maastrichtian pollen species: Ephedripites
multipartitus, Libopollis jarzenii, Liliacidites complexus (the most abundant species), Myrtipites
scabratus, “Proteacidites” spp., Retibrevitricolporites beccus, and Trisectoris costatus. Five of
the Maastrichtian species are present in the uppermost Cretaceous sample, 0-1 cm below the
parting; extinction of the Maastrichtian palynoflora is about 24% within 10 cm below the K-T
boundary. None of the Maastrichtian species is present in the lignite just above the parting, or
in lignite or carbonaceous claystone samples to the top of the measured section. In the
Paleocene samples, Arecipites tenuiexinous, Momipites inaequalis, Retitrescolpites
anguloluminosus, and Thomsonipollis magnificus are notably abundant. A fern-spore ―spike‖
has not been detected, but may be present within an unsampled 7-cm interval in the lignite
above the lowermost Paleocene sample.
          Shock-metamorphosed quartz grains are present within the parting and in the 1-cm-
thick sample of lignite just above it. Anomalous amounts of iridium have been detected in the
parting; detailed measurements are underway. The shocked quartz and iridium are debris
from the Chicxulub impact crater, and are evidence that the plant extinctions were caused by
the K-T impact event.
          Associated vertebrate fossils include hadrosaurian dinosaur teeth about 4 m below
the K-T boundary and the jaw of the Puercan (earliest Paleocene) mammal Protungulatum
donnae about 12 m above. Numerous megafloral assemblages reveal a Paleocene
megaflora that is low in diversity (9-15 taxa), and this low diversity persists for about 250 Kyr
into the Paleocene, based on calculations from the paleomagnetic data.
A NEW BIOSTRATIGRAPHY FOR THE LOWER PALEOCENE
ONSHORE WEST GREENLAND AND ITS IMPLICATIONS FOR
THE TIMING OF THE PRE-VOLCANIC EVOLUTION

H. NØHR-HANSEN, E. SHELDON
The Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350
Copenhagen K, Denmark
G. DAM
DONG E&P, Agern Alle 24-26,DK-2970 Hørsholm, Denmark

In light of new biostratigraphic data from Nuussuaq, it is possible for the first time to provide
an agreement between palynostratigraphic, nannostratigraphic, radiometric dating and
magnetostratigraphic measurements from relatively closely situated sections in a restricted
area in the North Atlantic Igneous Province; resulting in the dating of the initiation of volcanism
onshore West Greenland.
         On the basis of an integration of dinoflagellate cyst and nannofossil data, it has been
possible to divide the Lower Paleocene succession on Nuussuaq into five dinoflagellate cyst
zones (Trithyrodinium evittii, Cerodinium pannuceum, Senegalinium iterlaaense,
Palaeocystodinium bulliforme, Alisocysta margarita) and correlate with global nannoplankton
zonation.
         The uppermost pre-volcanic marine mudstone succession has been dated latest
Danian (upper NP4) based on nannoplankton. The first occurrence of hyaloclastites and
reworked volcaniclastic sandstones is broadly concurrent with the base of the Alisocysta
margarita Zone indicating that volcanism in West Greenland began during latest Danian. The
overlying and partly time equivalent volcanics were formed during chron C27n. These
hyaloclastites underlie volcanics of chron C26r, which are dated as 60.9 and 61.3 Ma by
40    39
  Ar/ Ar measurements
         Moreover, it is possible to date the events associated with rifting, tranquil uplift and
valley and submarine canyon incision of the basin that occurred immediately prior to the
volcanism in West Greenland.
         Three pre-volcanic tectonic phases have been recognised, all associated with valley
and submarine canyon incision. The first phase took place in the Late Maastrichtian and was
followed by two phases in the Early Paleocene. The two Early Paleocene events took place
during NP1–NP3, and were followed by rapid subsidence preceding volcanism in NP4.
LATERAL BIOFACIES CHANGES IN MID-CRETACEOUS HIGH-
RESOLUTION SEQUENCES IN THE U.S. WESTERN INTERIOR
F.E. OBOH-IKUENOBE
University of Missouri-Rolla, Department of Geology and Geophysics, 125
McNutt Hall, Rolla, M) 65409, USA
M.J. EVETTS
1227 Venice Street, Longmont, CO 80501, USA
J.M. HOLBROOK
Southeast Missouri State University, Department of Geosciences, Cape
Girardeau, MO 63701, USA
R.W. SCOTT
Tulsa University & Precision Stratigraphy Associates, RR3 Box 103-3,
Cleveland OK 74020, USA
D.G. BENSON, Jr
1522 Ehlinger Road, Fayetteville, TX 78940, USA

Upper Albian-Lower Cenomanian sandstone, siltstone and shale units in the U.S. Western
Interior represent several transgressive-regressive cycles associated with multiple marine
connections between the Gulf Tethyan and northern Boreal regions. The units extend laterally
for distances as great as 200 km and are separated by regional erosional contacts designated
as sequence boundaries (SB). The two seaways were fully connected during the early part of
the Late Albian when the Kiowa, Tucumari and Glencairn formations between SB2 and SB3
were deposited in the south, and the Thermopolis and Skull Creek formations were deposited
in the north. The connection closed during the later part of the Late Albian regression, but it
was re-established during the Early Cenomanian with the deposition of the Graneros Shale in
the south and the Belle Fouche Shale in the north.
         More than 40 sections (below SB3 to above SB4) in SE Colorado, NE New Mexico,
Oklahoma panhandle, Montana, and Wyoming have been studied to test the hypothesis that
ephemeral connections existed between the cooler Boreal Sea and the warmer Tethyan Sea
between SB3 to just above SB4. Such connections would have provided the opportunity for
south to north biotic exchanges. The multidisciplinary techniques of sedimentology, sequence
stratigraphy, palynology, micropaleontology, and organic geochemistry tentatively suggest that
the two basins were briefly connected twice during the latest Albian and/or earliest
Cenomanian. The occurrences of a low diversity agglutinated foraminiferal biota (e.g., Tethyan
Ammobaculites and boreal Miliammina), nearshore dinoflagellate cysts, such as
Cyclonephelium, Palaeoperidinium and Cribroperidinium, and the acritarch genus
Pterospermella in these sediments suggests that the ephemeral connections were so brief
that brackish conditions were established instead of fully marine conditions. This observation
is supported by isotopic carbon signals and palynofacies analysis. In addition, ranges of
dinoflagellate cysts are being calibrated with ammonites, in order to directly correlate the
Albian/Cenomanian boundary from France to Montana.
BIOSTRATIGRAPHY, SEQUENCE STRATIGRAPHY AND
PALAEOENVIRONMENTAL INTERPRETATION OF THE FIQA
FORMATION (UPPER CRETACEOUS), NORTH OMAN
S.R. PACKER
Millennia, Unit 3, Weyside Park, Newman Lane, Alton, Hants, UK
P.L. OSTERLOFF
XGL/3 Petroleum Development Oman LLC, PO Box 81, Muscat 113, Sultanate of Oman
J.B. FILBRANDT
XGL/5 Petroleum Development Oman LLC, PO Box 81, Muscat 113, Sultanate of Oman

Biostratigraphic studies have been undertaken to provide age dating and palaeoenvironmental
interpretation of the subsurface Fiqa Formation, Aruma Group (Upper Cretaceous) in North
Oman. These data have been integrated with 2-D seismic and field observations to develop a
model of evolving palaeoenvironments and depositional systems in the Santonian and
Campanian foreland basin of the Oman Mountains. The Aruma Group has previously been
subdivided into the Fiqa and Simsima Formations, with the Fiqa Formation being subdivided
into an upper carbonate prone Arada Member and lower clastic prone Shargi Member. The
focus of the analysis carried out here has been on the older units of this latter member, here
informally referred to as the ―Lower‖ and ―Upper‖ Shargi units. Twenty-four study wells and
outcrop sections have been analysed primarily for quantitative micropalaeontology,
supplemented by selected nannofossil analyses.
         The ―Lower Shargi‖ unit is represented primarily by deep-water shales overlying a
sequence boundary that separates terrigenous clastic deposition from the Natih carbonates,
following rapid submergence during the Coniacian to Santonian. The basal ―Lower‖ Shargi unit
shows spatial variability with localised preservation of thin Coniacian and Early Santonian
shallow water sequences. The main part of the ―Lower‖ Shargi is of Santonian to earliest
Campanian age. In the deeper parts of the foreland basin the top of the ―Lower‖ Shargi is
interpreted as an extensive erosional cut, possibly representing a coalescence of major slump
scars over a strike length of up to 100 km. This boundary signifies an important change in the
depositional evolution of the basin.
         The ―Upper‖ Shargi unit comprises sands and shales deposited in shelf or slope
environments, characterised by distinctive microfaunal assemblages. Convergent, onlapping
reflection geometries have been mapped on 2-D seismic data and can be related to
deposition of turbiditic sheet-sands in a deep-water environment during the Early Campanian.
The Campanian shelf to the south was dominated by shales apparently by-passed by coarser
clastic sediments. Infill of the basin was rapid and coincided with an increase in water depth
during the mid-Campanian, resulting in submergence of the clastic source area to the
southeast.
         The studies carried out to date have begun to document the biotic characteristics of
‗black‘ shale facies during the Late Cretaceous of the Middle East and have implications for
the global characterisation of these deposits within the Tethyan realm and their application to
exploration stratigraphy.
MUNGO FIELD UKCS 22/20: BUGS, A DOSE OF SALTS, AND
RESERVOIR DEVELOPMENT

S.N.J. PAYNE
BP Exploration Operating Company Ltd, Burnside Road, Farburn Industrial Estate, Dyce,
Aberdeen, AB21 7PB, UK
P.A. CORNICK
Petrostrat Ltd, Tyldesley House, 48 Clarence Road, Craig-y-Don, Llandudno, LL30 1TW, UK
L.F. DRAPER
BP Exploration Operating Company Ltd, Burnside Road, Farburn Industrial Estate, Dyce,
Aberdeen, AB21 7PB, UK
H. NICHOLSON
BP Norge, Godesetdalen 8, PO Box 197, 4065 Stavanger, Norway

Mungo is an oil and gas field located within the Eastern Trough of the UK Central North Sea,
250km east of Aberdeen. Discovered in 1989 with initial reserves estimated at 155 million
barrels of oil and 79 bcf of gas, the field comprises a salt diapir flank structure reservoired
largely within Paleocene turbidite sandstones, sealed beneath Eocene mudstones with an up-
dip termination against Zechstein salt.
         Biostratigraphic data from early wells suggested extreme geological complexity;
reworking, caving and injection were all invoked. Guided by the principle that the dinocyst
genus Apectodinium does not migrate into the North Sea until the S1a Unit of the Forties
Member, interpretation focused on identifying the LDO of this genus. Once identified, this
―golden spike‖ became the key to interpreting well stratigraphy. The complexity thereby
imposed fitted notional models of a ―Forties melange‖ reservoir, with older sediments
chaotically slumped or reworked off the growing diapir. Inter-well correlation was rendered
doubtful and the Mungo reservoir model was thereafter constructed stochastically.
         Continued development drilling induced a further attempt to unravel the subsurface
complexity. Emphasis was changed, downplaying the Apectodinium driven model, seeking
instead any ghosting of an in-situ stratigraphy in the ―melange‖. Re-analysis of biostratigraphic
and core material, combined with heavy mineral analysis, has allowed a rationalisation. The
prime reservoir is now assigned to the Maureen Formation, albeit with major Forties injection.
The mechanism for this injection may involve the fissuring of older sediments due to diapir
extension, allowing the entrainment of younger material. The revised stratigraphy allows eight
Paleocene packages to be identified, important for reservoir layering, correlation and
biosteering.
THE GLACIGENIC AL KHLATA FORMATION OF OMAN:
BIOZONATION AND APPLICATIONS

R.A. PENNEY
Reservoir Laboratories AS, PO Box 96, Mina Al-Fahal PC 116, Sultanate of Oman
P.L. OSTERLOFF
XGL/3 Petroleum Development Oman, PO Box 81, Muscat PC 113, Sultanate of Oman

A refined biozonation of the Permo-Carboniferous Al Khlata Formation, Sultanate of Oman, is
presented for which the number of subdivisions is increased from four to ten. Owing to the
extensive reworking of palynomorphs within these sediments, as a result of episodic glacial
cover, the scheme is based mainly upon quantitative assessments of broad taxonomic
groupings instead of inceptions and extinctions of individual taxa. The variation in the
proportion of these components upwards through the Al Khlata is a reflection of the
palaeoevegetational change through time, which is thought to be the product of Oman‘s
changing latitudinal position and climatic amelioration associated with the waning of the
Permo-Carboniferous Gondwanan glaciation.
           This refinement of the palynostratigraphy improves the correlation potential for other
Gondwanan sections both within and beyond the Arabian Plate. Comparison with other
palynomorph zonation schemes from within the Gondwanan realm suggest an age range for
the Al Khlata from the Latest Moscovian (Westphalian D) to the Sakmarian, when related to
faunal datings from Australian sections and their Russian correlatives.
           Examples of four scales of practical application are given. Firstly, on the exploration
scale, where the core and sidewall core based zonation facilitates and constrains regional
correlation of sequences, such that major depocentres and plays can be identified with
associated reservoirs and seals. Secondly, production field scale reviews of reservoir
architecture, to facilitate future drilling strategies. Thirdly, in updating existing field models by
post-drill palynostratigraphic evaluation of cuttings samples in horizontal wells. Fourthly, by
near ―real time‖ monitoring of horizontal well sections, where palynomorph recovery in cuttings
samples permits. In both the latter cases, the utilisation of palynological data from existing
and pilot verticals, plus wireline log and/or wellsite lithological information, is essential for the
interpretation of the palynological and kerogen signatures from the sub-horizontal sequences.
In all, this improved palynostratigraphic scheme has enhanced the exploitation of South
Oman‘s Al Khlata reservoirs substantially, saving millions of dollars in field development costs,
in addition to providing data for near field and regional exploration.
CASE BASE REASONING AND PATTERN MATCHING IN
SEQUENCE BIOSTRATIGRAPHY

E. PLATON, A.C. GARY, G.W. JOHNSON
Energy and Geoscience Institute, Univeristy of Utah, 423 Wakara Way, Suite 300, Salt Lake
City, UT 84108, USA

A two-way correlation exists between paleontology and sequence stratigraphy. On one hand,
temporal and areal distribution of fossils provides useful insights into deciphering
environmental changes that can be related to sequence-forming processes and/or help in
determining the geological age of a given sequence stratigraphic horizon. On the other hand,
sequence stratigraphy can help, in a predictable fashion, the recognition and the interpretation
of patterns of paleobiologic change. It is evident that paleontological work can provide more
information about sequence stratigraphy contributing with more than just bioevents
constraining the age or correlation of horizons. Body and trace fossils as well as their
taphonomy provide useful information about the paleoenvironmental parameters and thus help
the identification and interpretation of parasequences and sequences. Parameters such as
water depth, substrate consistency, turbidity, and bottom water oxygenation seem to be
essential for sequence stratigraphy.
           Few biostratigraphic software packages and the associated databases help us
perform stratigraphic analysis, correlation, and interpretation. It is however, evident that
geoinformatics did less in the areas of paleoenvironmental analysis and sequence
biostratigraphy. Advanced information technologies such as Machine Learning techniques
were used for lithologic interpretation of the well logs but no attempt has been made to
implement artificial intelligent systems for complex analyses of paleontological data. An
artificial intelligent system meant to provide assistance in the area of sequence biostratigraphy
is currently developed at the Energy and Geoscience Institute. A combination of technologies
that includes Case Base Reasoning (CBR) and Artificial Neural Networks (ANN) are used for
identifying paleoenvironmental solutions, recognition of well log features indicative of
sequence stratigraphic surfaces, and integration. For the correlation of well data with regional
seismic lines a component meant to construct synthetic seismograms is to be implemented.
Paleoenvironmental, sequence biostratigraphic, and taxonomic knowledge is built in a case
base stored in a relational, SQL based database. On short, finding solutions to a new problem
implies retrieving similar experience about similar situation from the case base and reusing
the experience in the context of the new situation. If a good match exist between the new
problem and one of the cases in the case base, a complete use of the existing solution is
taking place. If this match is only partial, a partial reuse of the old solution is taking place. At
this point, more knowledge can help developing a new case and the associated solution. This
is subsequently stored in the case base. A backpropagation neural network is trained to
perform classification of those features of the wireline logs that help identify sequence
stratigraphic surfaces.
VEGETATION, CLIMATE AND CYCLOSTRATIGRAPHY IN
CENTRAL PARATETHYS DURING LATE MIOCENE AND
EARLY PLIOCENE ACCORDING TO PALYNOLOGY

S.-M. POPESCU
PEPS, UCBL, 27-43 Boulevard du 11 Novembre, F69622 Villeurbanne Cedex (France)

High-resolution palynological analysis has been performed on five well-dated Early Pliocene
sections from southeastern Europe: Hinova, Valea Visenilor, Husnicioara and Lupoaia in the
Dacic Basin (southwestern Romania), DSDP Site 380A (Black Sea) which also includes latest
Miocene sediments (Messinian).
         Pollen floras show how this region was relatively protected from floristic extinctions
which occurred in Europe during the Late Pliocene and the Quaternary because of glacial-
interglacial cycles. A noticeable effect of Asian monsoon has probably encouraged
persistence in this area of some themophilous species up today.
         Altitudinal forest belts have been reconstructed on the southern Carpathians. Palaeo-
Danube delta was rich in swamps inhabited by Cypress forest and marshes occupied by
grasses (Cyperaceae) as today in Florida and Mississippi delta. The descent of the altitudinal
gymnosperm belts is evidenced in relation with each ―cooling‖ with respect to eccentricity 100
kyrs cycles. On contrary, warmer phases forced development of thermophilous trees and
lignite deposition. Asian monsoon probably controlled opposing development of swamps and
marshes with respect to precession 20 kyrs cycles. Precession minima (monsoon
enhancement) advantaged marshes which requires more humidity than swamps. A
comparison is possible with the Mediterranean sapropels, the forcing of which being also the
precession rhythm. This suggests the establishment in Early Pliocene of a longitudinal
gradient over the Mediterranean region. As today, a strong contrast separated vegetation
features from Dacic and Pontic realms. In the latter, thermic cycles forced competition
between thermophilous trees and Artemisia steppes, the early development of which
announces their forthcoming development over the whole Mediterranean region in relation
with earliest glacials (2.6 Ma).
         Such high-resolution pollen analyses provide a very detailed climatic record for the
region with respect to global climatic changes between 6 and 3.8 Ma. Resolution of pollen
                                         18
records reaches that of reference ? O curves. So, weak variations in temperature and
humidity occurring during the warm Pliocene will be more understood as well as their effects
on the vegetation. The European Pliocene climatostratigraphy is confirmed and Central
Paratethyan deposits receive for the first time a reliable cyclostratigraphy. Relationships will be
easier with the reference Mediterranean marine sections.
         Consequences of the Mediterranean Sea desiccation (Messinian salinity crisis: 5.7-
5.32 Ma) over the Black Sea have been evidenced: they concern both coastal vegetation and
dinoflagellate assemblages. A new idea of Mediterranean Sea – Central Paratethys
relationships is proposed for a better explanation of the events bordering the salinity crisis.
LATE MAASTRICHTIAN DINOFLAGELLATE CYSTS FROM
CERRO BUTALÓ SECTION, SOUTHERN MENDOZA
PROVINCE, ARGENTINA

M.B. PRÁMPARO, O.H. PAPÚ
Unidad de Paleopalinología. Instituto Argentino de Nivologia, Glaciologia y Ciencias
ambientales (IANIGLA)- CRICYT. C.C.131. (5500) Mendoza, Argentina

The late Cretaceous Atlantic trangression is recorded in western Argentina in the sediments of
the upper part of the Malargüe Group. The Cerro Butalo section crops out at 35º 50' S and 69º
40' W, southern Mendoza Province, Argentina and is constituted by sediments of the Jagüel
Formation and Roca Formation, both belonging to the Malargüe Group. The Jagüel Formation
at the study area is 25m thick and is characterized by grey mudstones and sandstones. The
Roca Formation overlies the preceding unit and comprises a basal white limestone (30m
thick) with abundant bivalves and gastropod fragments, followed by pelitic sandstones (20 m
thick). These two units correspond to the third depositional sequence (DSIII) in the sense of
Parras et al. (1998), deposited in a subtidal to intertidal environment, and are overlain by the
terrestrial Pircala Formation.
         A well preserved palynological association was recovered from this section.
Dinoflagellate cysts are dominating in the lower part of the profile (Jagüel Formation).
Representatives of the Spiniferites/Achomosphaera group dominate the association.
Biotratigraphically useful species are Areoligera medusettiformis, Areoligera coronata,
Deflandrea galeata, Glaphyrocysta retiintexta, Hystrichosphaeridium tubiferum, Phelodinium
magnifica, Palaeocystodinium lidiae, Paleocystodinium golzowense, Piercites pentagona.
Several species of the genera Cordosphaeridium, Florentinia and Tityrosphaeridium are also
common in this interval. Terrestrial palynomorphs are scarce in all the samples but become
more abundant at the top of the section (Roca Formation). Spores and massulae of aquatic
ferns (Azolla cretacea, Azolla (Rhizosperma) sp., Azollopsis (Spiralopsis) pusilla,
Grapnelispora loncochensis) reflect the vegetation of the littoral environment and are
stratigraphically useful. Gymnosperm pollen like Classopollis, Callialasporites, Cyclusphaera,
Podocarpidites are present, associated with angiosperm pollen assigned to Psilatricolporites
patagonicus, Peninsulapollis gillii and the zygnematacean algae Catinipollis.
         Deflandrea galeata has a first occurrence in the middle Late Maastrichtian of the
Danish part of the North Sea. Disphaerogena carposphaeropsis has its first appearance
(FAD) in the Late Maastrichtian (67.0 M.A.). Based on the occurrence of these two species,
the Jagüel Formation at the Cerro Butalo section is considered to be of Late Maastrichtian
age. Within the uppermost 10m of Roca Formation dinoflagellate cysts become scarce; only
specimens belonging to Operculodinium centrocarpum are present, indicating a nearshore
depositional environment. The KPB at this section is considered to be (paleontological
evidence and radiometric dating) located in the continental deposits of Pircala Formation
(DSIV). This is the first report of a Late Cretaceous dinoflagellate cysts association of the
Mendoza Province, western Argentina.
SHORT-TERM ENVIRONMENTAL CHANGE DURING MID-
CRETACEOUS BLACK SHALE FORMATION:
MICROPALEONTOLOGICAL EVIDENCE FROM THE UPPER
APTIAN AND LOWER ALBIAN OF THE VOCONTIAN BASIN (SE
FRANCE)

J. PROSS, J.O. HERRLE, O. FRIEDRICH, C. HEMLEBEN
Institute of Geosciences, Sigwartstr. 10, D-72076 Tübingen, Germany

In order to better understand paleoclimatic and paleoceanographic changes during the mid-
Cretaceous, we have studied palynomorphs, calcareous nannoplankton, and benthic
foraminifera from black shales in the Vocontian Basin (SE France). To assess the
mechanisms leading to black shale formation on different scales, the supraregionally
distributed Niveau Paquier Paquier (Oceanic Anoxic Event 1b, Early Albian) and the regionally
distributed Niveau Kilian (Late Aptian) were investigated. As both the Niveau Paquier and the
Niveau Kilian formed under relatively high sea level in basically identical paleo-latitudes, a
framework is provided to compare the formation of obviously different black shales under
partly identical boundary conditions. We used palynomorphs as a proxy for terrestrial input
and humidity, calcareous nannofossils as a proxy for surface water temperature and
productivity, and benthic foraminifera as a proxy for bottom water oxygenation and organic
matter flux.
         For the supraregionally distributed Niveau Paquier, our data show short-term
increases in terrigenous input, humidity, temperature, and productivity associated with
decreases bottom water oxygenation. The signals occur within the precessional band and are
modulated by eccentricity. As can be inferred from the high spore/pollen ratio in the Niveau
Paquier samples, the formation of the Niveau Paquier generally occurred under extremely
humid conditions.
         The regionally distributed Niveau Kilian shows environmental changes similar to those
occurring during formation of the Niveau Paquier. Differences exist, however, in the duration
of black shale formation and the amplitude of changes. They are related to the extent of
humidity and temperature increases during black shale formation. The spore/pollen ratio in
samples from the Niveau Kilian is much lower than in those from the Niveau Paquier,
indicating generally less humid conditions during its formation.
         The environmental changes leading to black shale formation and the differences in
the amplitude of these changes are explained through a model invoking monsoonally driven
alterations in evaporation/precipitation and temperature patterns. The intensity of humidity and
temperature increases controlled whether black shales developed on a regional or
supraregional scale. The supraregionally distributed Niveau Paquier formed under extremely
humid and warm conditions when monsoonal intensity was strongest and, as a result of
increased humidity, low-latitude deep water formation was diminished. The regionally
distributed Niveau Kilian formed under less increased humidity and warmth, with low-latitude
deep water formation being reduced to a lesser extent and/or on a regional scale only. The
threshold for the formation of a supraregional black shale was not reached.
PLANT DNA IN PREHISTORIC COPROLITES: EVIDENCE OF
DIET OR CONTAMINATION

K.J. REINHARD
School of Natural Resource Sciences, 214 Bessey Hall, University of Nebraska – Lincoln, NE
68588-0340, USA
S.A. de MIRANDA CHAVES, A. IÑIGUEZ
Fundação Oswaldo Cruz - Escola Nacional de Saúde Pública (ENSP) - Departamento de
Endemias Samuel Pessoa, Rua Leopoldo Bulhões 1480, térreo - Manguinhos. Cep 21041-
210 Rio de Janeiro - RJ, Brasil

DNA from Hinds Cave coprolites dating to more than 2,000 years ago included chloroplast
DNA sequences. The chloroplast sequences were interpreted as evidence of diet. We
analyzed 19 Hinds Cave coprolites to evaluate the potential sources of the chloroplast DNA.
Using the latest applications of phytolith analysis and pollen concentration, we determined that
many of the chloroplast sequences are likely contaminants from ambient pollen. We then
propose a methodology of excavation and analysis that will increase the utility of molecular
methods applied to the reconstruction of diet and environment in ancient times from
coprolites.
COMPARISONS OF THE JURASSIC PALYNOMORPH RECORD
IN THE NORTHERN HEMISPHERE ANDS AUSTRALIA

J.B. RIDING
British Geological Survey, Keyworth, Nottingham NG12 5GG, UK

The Jurassic dinoflagellate cyst records in the Northern Hemisphere and Australia and
surrounding regions exhibit certain incoherencies. The ranges of some cosmopolitan taxa are
apparently significantly different. For example, the range top of Rigaudella aemula is
significantly younger in Australia than in Europe. It is likely that palaeogeographical and/or
palaeolatitudinal factors, rather than reworking, may explain some of the disparities. Long-
range macrofaunal correlations are more problematical than palynological ones because
molluscs exhibit much more endemism than palynomorphs and other microfossils.
Approaches other than standard species range analysis may prove useful to global
correlations; these include statistical methods of assemblage characterisation and
geochemical dating.
         The principal areas of similarity and disparity are analysed in this assessment of the
existing literature. The basic units analysed are the constituent biozones in the four Mid
Triassic to Valanginian Superzones of Helby and others (1987), the standard Australian
palynological zonation.         The Shublikodinium Superzone (Anisian-Pliensbachian) is
characterised by low diversity dinoflagellate cyst associations. Despite the presence of
endemic Australasian forms, several key bioevents allow a good correlation with Europe. For
example, the Rhaetogonyaulax rhaetica Interval Zone in Australia is deemed to be of late
Rhaetian age due to the abundance of the index species; also the top of the Superzone is
interpreted as being earliest Sinemurian, rather than Pliensbachian. The overlying Luehndea-
Susadinium? Assemblage is a low-diversity early Toarcian dinoflagellate cyst assemblage
which was developed in marginal marine conditions and probably reflects the early Toarcian
eustatic rise. In the early Bajocian to late Callovian Pareodinia ceratophora Superzone of
Australia, all the constituent zones appear to be considerably older than the ages originally
suggested, based on European dinoflagellate cyst datums. The most reliable macrofossil tie
point occurs in the lowermost part of this Superzone. This is the molluscan fauna of the
Newmarracarra Limestone of Western Australia, which is early Bajocian in age and the
dinoflagellate cyst floras of the Dissiliodinium caddaense Oppel Zone are consistent with this
interpretation. The development of the major dinoflagellate cyst lineages at this time appears
to be similar worldwide. The three zones of the Oxfordian Pyxidiella Superzone and the
lowermost five zones of the late Oxfordian to Berriasian/Valanginian Fromea cylindrica
Superzone are also interpreted to be older than originally envisaged. Hence this trend is a
consistent one. However, the uppermost four zones of the Fromea cylindrica Superzone are
deemed to be of similar ages to those originally assigned to them. Endemism is at its greatest
during the Fromea cylindrica Superzone; this is a result of the generally regressive eustatic
regime at this time.
PALYNOSTRATIGRAPHIC AND GEOLOGICAL SETTING OF
THE LATE OXFORDIAN – EARLY VOLGIAN FULMAR
FORMATION RESERVOIR OF THE JANICE FIELD (BLOCK
30/17A, UK NORTH SEA).

L. RILEY
BVR International Ltd, 64 South Street, Epsom, Surrey, KT18 7PH, UK
P.D. WARE
Kerr McGee North Sea (U.K.) Ltd, Ninian House, Altens, Aberdeen AB12 3LG, UK
P. WORTHINGTON
BVR International Ltd, 64 South Street, Epsom, Surrey, KT18 7PH, UK
M. QUINE
Kerr McGee North Sea (U.K.) Ltd, Ninian House, Altens, Aberdeen AB12 3LG, UK

The Upper Jurassic fairway of the southwest Central Graben has proven to be a prolific oil-
producing area since the initial discovery of the giant Fulmar Field by Shell UK in 1975.
Subsequent significant discoveries include BP‘s Clyde Field and satellites (Leven and Medwin)
and Talisman operated Halley Field (formerly Amoco). The Janice Field, located in block
30/17a, was initially discovered by Phillips Petroleum in 1990 and is the latest commercial find
in this area of the Central Graben. Operatorship of the field was transferred to Kerr McGee
North Sea (U.K.) Ltd. in 1995 for appraisal and development.
         Hydrocarbons are principally trapped within combination structural/stratigraphic traps
located on a series of fault terraces, which form the western margin of the Central Graben.
The main reservoir comprises very fine to medium-grained bioturbated shallow marine
sandstones of the Fulmar Formation which, within the field area are well dated palynologically
as Late Oxfordian through Early Volgian (J54? – J66A). Reservoir seal is provided by the
Kimmeridge Clay Formation (J66B – J76), which is also the hydrocarbon source, and the Late
Cretaceous Chalk Group where the reservoir is truncated by the base Cretaceous
unconformity.
         Palynostratigraphic criteria allow for the division of the Janice Field Fulmar Formation
into four broad layers, based on major marine flooding surfaces that correlate directly to
Partington et al.’s (1993) ―J Sequence‖ events: In ascending stratigraphic order; Paralic Unit
(?J54), Lower Fulmar (J62), Middle Fulmar (J63) and Upper Fulmar (J64 – J66A). Ongoing
revisions to the palynostratigraphic framework during the course of appraisal drilling have
subsequently modified the field model and intra-field well correlations by for example removing
the major ―Upper‖, ―Middle‖ & ―Lower‖ Fulmar thickness changes as originally maintained
between wells 30/17a-10, 30/17a-11 in the 1987 Annex B application. This revised reservoir
stratigraphy, initially based on the palynostratigraphic database, has been further refined and it
now allows for the recognition of 15 genetic units. The current field model maintains a
correlative subdivision of the Fulmar Formation reservoir into theoretical ―flow units‖,
separated by low permeability zones (baffles) and/or barriers, whilst still maintaining the
overall palynostratigraphic integrity.
         Janice Field stratigraphy is also reviewed in a regional stratigraphic/ geological setting
as part of an on going regional Upper Jurassic prospectivity study. The Late Oxfordian – Early
Volgian Janice Field Fulmar Formation reservoir is demonstrated as being part of an overall
southwards younging (Middle Oxfordian – Early Valanginian) back-stepping package of
genetically stacked shallow marine sandstones, which relates to on going phases of fault-
related Late Jurassic – earliest Cretaceous extension.
MICROFOSSIL-CALIBRATED TIME SCALE FOR THE UPPER
CRETACEOUS – WIDER UTILITY FOR ABSOLUTE AGE
CONTROL IN INDUSTRY AND ACADEMIA

P.J. SIKORA, R.W. HOWE
Energy & Geoscience Institute; University of Utah; 423 Wakara Way, Ste 300; Salt Lake City,
UT 84108, USA
A.S. GALE
Department of Palaeontology, Natural History Museum, Cromwell Road, London SW7 5BD,
United Kingdom
J.A. STEIN
256 Main Street, Danville, NY 14437, USA

There is an acute need for a recalibrated Cretaceous time scale by both industry and
academia. The most recent time scale (e.g. Gradstein et al., 1995) and sequence
chronostratigraphic chart (de Graciansky et al., 1999) are macrofossil-based, limiting their
utility, especially for global calibration. The Cretaceous microfossil datums posted on the new
sequence chronostratigraphic chart are a relative biostratigraphic zonation, not directly
calibrated to the absolute time scale. Furthermore, the listed microfossil zonations were
developed separately from each other with no integration between groups. Absolute-age
calibration of integrated multidisciplinary microfossil datums results in a Cretaceous time scale
that is a much more useful tool for industry and academia, with greater geographic and
stratigraphic scope resulting from the abundant recovery of microfossils and the ease of their
use in core and ditch-cuttings samples.
           Construction of the time scale began by integration of biostratigraphic datums
(planktonic foraminifera, nannofossils and, to a more limited extent, dinoflagellates) with
macrofossil, paleomagnetic and radiometric datums. Calibration of the datums to absolute
time was conducted via orbital cyclostratigraphy, deriving a precessional signal on the order of
20kyr. In addition, combining the cyclostratigraphic results with detailed analyses of proposed
stage boundary stratotypes for the Cretaceous (Rawson et al., 1996) resulted in more
accurate stage boundary ages and stage duration estimates.
           The recalibration of the Coniacian and Santonian stages is provided as an example
of the methodology of time-scale construction. The Coniacian/Santonian recalibration resulted
from a cyclostratigraphic study of the Niobrara Chalk in western Kansas and northeast New
Mexico. Cyclostratigraphy was defined based upon carbonate content and magnetic
susceptibility measurements and was then used to calibrate biostratigraphic, paleomagnetic
and radiometric datums in absolute time. These results are then combined with analyses of
the proposed boundary stratotypes for the Coniacian and Santonian (Rawson et al., 1996) in
the USA, U.K. and Germany, allowing a recalibration of the stage durations.
INTEGRATED STRATIGRAPHY OF THE PALEOCENE-EOCENE
TRANSITION IN PLATFORM TO BASIN SEDIMENTS IN EGYPT

R.P. SPEIJER, C. SCHEIBNER, J. KUSS
Geosciences Department, Bremen University, 28334 Bremen, Germany
A. MACKENSEN
Alfred Wegener Institute, 27568 Bremerhaven, Germany
A.M. MARZOUK
Geology Department, Tanta University, 31527 Tanta, Egypt
S. MONECHI
Geosciences Department, Florence University, 50121 Florence, Italy
A.M. MORSI
Geology Department, Ain Shams University, 11566 Cairo, Egypt
C. MÜLLER
Geosciences Department, Bremen University, 28334 Bremen, Germany
J.J.G. REIJMER
GEOMAR, 24148 Kiel, Germany

The Paleocene-Eocene thermal maximum (PETM; ~55 Ma) represents a brief period of global
warming. Turnovers and innovations among marine microplankton, benthic foraminifera,
ostracoda, and terrestrial mammals associated with a negative carbon isotopic excursion
enable global correlations between marine and terrestrial deposits. The onset of the isotopic
excursion is going to be the criterion to delineate a redefined P/E boundary and its GSSP
(Global Stratotype section and Point) will probably be designated in the recently discovered
Dababiya section in eastern Egypt. The stratigraphy, micropalaeontology and geochemistry of
several reference sections in the same basin have been studied intensively during the last
decade. Most recent findings (e.g. Speijer and Morsi, 2002, Geology 30: 23-26) suggest a
sharp sea-level fall just prior to the PETM, immediately followed by a sea-level rise, possibly
correlative with sequences TA2.2/TA2.3 of Haq et al. (1987, Science 235: 1156-1167). In
contrast to these basinal successions, carbonate platforms represent a setting in which there
is still major uncertainty with respect to positioning the PETM. The Galala Mountains, Eastern
Desert, provide a well exposed 40-km-long transect across a Paleocene-Eocene prograding
carbonate platform interfingering with basinal marls, forming an ideal stage for investigating
the biotic and biosedimentary consequences of the PETM in a platform setting. An integrated
stratigraphic framework for the transect is based on planktic foraminifera, smaller and larger
benthic foraminifera, calcareous nannofossils, ostracodes, stable isotopes and -ray
recordings. Especially the sections located at the platform-basin transition, containing
hemipelagic deposits with intercalated mass-transported platform deposits have a high
potential to achieve a direct correlation between the platform and basin stratigraphies. In
basinal successions, the PETM is situated within standard Zones NP9 (nannofossils) and P5
(planktic foraminifera). Preliminary results suggest that this level coincides with the base of
Shallow Benthic Zone 5, and the start of adult dimorphism and large shell size of larger
foraminifera such as Nummulites, a main event in the evolution of Paleogene larger
foraminifera. It seems as if during the PETM, carbonate platform environments were affected
more severely than previously thought.
ESTIMATION OF PALEODEPTH BY TRANSFER EQUATION OF
RANGE DISTRIBUTION OF BENTHIC FORAMINIFERA AND
APPLICATION TO SEQUENCE BIOSTRATIGRAPHY:
EXAMPLES FROM THE ERATOSTHENES SEAMOUNT
(EASTERN MEDITERRANEAN) AND FROM THE AUSTRIAN
MARINE MIOCENE (PROJECT P13743-BIO)

S. SPAZZAFERRI, J. HOHENEGGER
Institute of Paleontology, Geo-Zentrum, Althanstrasse 14, 1090 Vienna, Austria
F. RÖGL, S. CORIC
Natural History Museum, Burgring 7, 1014 Vienna, Austria

It is well know that global eustasy plays an essential role in shaping depositional
sequences laid down in response to changes in relative seal level, and that surfaces of
depositional sequences are expected to be synchronous between basins. A sea level
change basically varies the depth below sea level, in other words the paleobathymetry.
Correct estimates of paleobathymetry are essential in paleoceanography and basin
analysis to reconstruct uplift and subsidence story of basins and to construct sea-level
curves. Therefore, demand for accurate paleobathymetrical techniques has largely
increased in the past decades. However, this demand has by no means been completely
satisfied.
           We present here the application of a simple method to estimate the paleodepth
of sediments from deep-sea, continental margins and enclosed basins based on a
transfer equation using the geometric mean of the range distribution of benthic
foraminifera.
           We have successfully tested this method on living assemblages collected at
know depth and successively we have applied it to the fossil record. In particular,
comparison of the paleodepth curve obtained for the Messinian to Pleistocene
sedimentary sequence drilled on the Eratosthenes Seamount (ODP Leg 160) with the
global smooth oxygen isotope curve, considered as proxy for se level changes, indicate a
relation between single excursions of our paleodepth estimates and sea level changes.
           Paleodepth curves obtained for several Karpatian to Badenian (Early to Middle
Miocene) outcropping and drilled sections in the Central Paratethys (e.g. Wagna Section
and Perbersdorf-1 Borehole) can also be correlated with the global smooth oxygen
isotope curve. In particular, the positive oxygen isotope excursion MLi-1 corresponds to a
well defined unconformity and water depth shallowing in the Styrian Basin.
TERTIARY PALYNOLOGY OF NON-MARINE SEDIMENTS,
MUGLAD BASIN, SUDAN
D.T. STEAD
Wellstrat Services Ltd., 51 Kirkett Avenue, Higher Kinnerton, Flintshire, CH4 9BN, UK
M.Z. AWAD
Greater Nile Petroleum Operating Company, P.O. Box 479, Hotel Palace, Khartoum, North,
Sudan

The Muglad Basin is part of the Central and West African Rift System that started to develop
during late Jurassic/ early Cretaceous time. The system evolved through three rift cycles
spanning Neocomian to Cenomanian, Coniacian to Maastrichtian and Palaeocene to
Pliocene. In this work the results of a palynological study of selected wells from the Muglad
                                                                        th
Basin, Sudan are presented. These wells, Amal –1 and May 25 , together, allow for
palynological analysis of a nearly complete Tertiary section (Quaternary to Palaeocene) which
was developed during the last rift cycle. Five Zones have been recognised, most of which are
further divided into two sub-zones. The Zones are (i) Graminaceae – Chenopodipollis
microporatus (Quaternary; Post-Adok Formation); (ii) Verrucatosporites spp. (Pliocene –
Miocene; Adok Formation); (iii) Cyathidites minor – Perfotricolpites digitatus (Miocene –
Oligocene; Tendi Formation); (iv) Striatopollis spp. (Oligocene – Eocene; Nayil Formation); (v)
Mauritiidites crassiexinus – Echimonocolpites rarispinosus (Palaeocene; Amal Formation).
The characteristics of each zone and corresponding sub-zones are discussed.
COMBINED RESERVOIR-SCALE PALYNOSTRATIGRAPHY
AND d13Corg STRATIGRAPHY FOR EARLY PERMIAN OIL-
BEARING GLACIGENE ROCKS IN OMAN
M.H. STEPHENSON
British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK
M. LENG
National Isotope Geoscience Laboratory, Keyworth, Nottingham, NG12 5GG, UK
P.L. OSTERLOFF
Petroleum Development Oman, PO Box 81, Muscat 113, Sultanate of Oman

Palynological study of the Early Permian Gharif and Al Khlata Formations of Oman has
allowed a high-resolution biozonation based on the microfloral changes occurring during a
period of deglaciation after the Permo-Carboniferous glacial episode. The biozonation enables
correlation to within a few meters within fields, and to within a few tens of metres between
fields. This represents a great increase in precision over previous schemes and is the most
precise palynozonation yet developed for Permian clastic rocks.
                              13
         A parallel study of d Corg (kerogen) of palynological samples has shown that many of
                                                             13                    13
the palynological events are reflected in the stratigraphic d Corg signature. The d Corg trends
                                                                       13
mark changes in gross plant types, though a more subtle secular d Corg variation related to
climate change and Permian global warming is also probably present. The signature can be
used, on a reservoir scale to corroborate palynological trends and may allow correlation where
palynological samples have sparse pollen/spore yield.
         The biozonation covers a period within the Asselian and Sakmarian stages of the
Early Permian and utilises both quantitative changes and first and last appearance datums. In
addition, the nature of some of the palynological and isotopic events allows correlation with the
new sequence stratigraphic scheme developed for the Arabian Plate by Sharland et al. (2001).
One of the events probably represents a eustatic deglacial relative sea level rise and as such
is an important datum for correlation across the Early Permian of Gondwana.
SECULAR CHANGES IN MARINE ECOSYSTEMS MAY
DRIVE PLANKTON EVOLUTION

P.K. STROTHER
Weston Observatory, 381 Concord Road, Weston MA 02493 USA

Recent research in marine geochemistry and earth systems history indicates that the
chemistry of the world‘s oceans has not been constant over time. Taxon diversity trends in
fossil organic-walled phytoplankton (OWP) track these large-scale cycles in seawater chemistry
more closely than benthic marine invertebrate taxon diversity. (The record of nekton, on the
other hand, does appear to correspond to OWP diversity, especially with respect to the terminal
Devonian extinction.) This suggests that benthic marine invertebrates are, to a large extent,
trophically buffered from the phytoplankton, and recent discoveries of increasing complexity in
                                                                                         -
marine microbiology support this idea. If shifts in the availability of Mg, Ca, and HCO 3 affected
the evolution of the phytoplankton, then the Phanerozoic decline in atmospheric pCO2 may
have affected phytoplankton evolution as well. This is because surface concentration of
dissolved CO2 is in equilibrium with the atmosphere. Phytoplankton groups vary in their range
of Rubisco efficiencies and carbon concentration mechanisms ( CCMs). These factors
effectively determine the ability of phytoplankton to assimilate carbon. Falkowski and Raven
have demonstrated that phytoplankton have progressively evolved more efficient Rubisco over
time. Thus, the phytoplankton of both Paleozoic and Mesozoic seas may have evolved more
in response to CO2 availability than limiting nutrient (N and P) availability.
         It is now imperative to take into account secular changes in both ocean water and
atmospheric chemistry, when examining the geologic history of the plankton and the trophic
structure of former oceans. The (rather pervasive) notion that the plankton, when viewed over
geologic time, responded primarily to sea level and/or N and P availability could be too narrow
a view of the range of extrinsic factors that have actually driven evolution in marine
ecosystems. The evolutionary response of phytoplankton to declining CO 2 over Phanerozoic
time is a new model for explaining the differences between the phylum-level composition of
Paleozoic and Mesozoic seas.
THE IMPORTANCE OF DINOFLAGELLATE CYSTS IN
TURBIDITE STRATIGRAPHY: CASE STUDIES FROM THE
LOWER CRETACEOUS AND TERTIARY OF THE TETHYAN
REALM

S. TORRICELLI
ENI S.p.A., Agip Division, P.O. Box 12069, 20100 Milan, Italy

         Turbidite successions of the Mediterranean area have often yielded scarce and/or
discontinuous recovery of foraminifers and calcareous nannofossils, the main tools used in the
Italian academies for traditional biostratigraphic investigations in this kind of sediments.
Accordingly, age and position of several turbidite formations in the regional stratigraphic
framework and related paleogeodynamic models for the Alps/Apennines orogenic system,
have always been much-debated questions.
         Three case histories are presented in which the study of palynological assemblages
recovered from turbidite suites cropping out in Tunisia and Italy led to unambiguous age
assessments with unprecedented precision, thus enabling regional correlations. In all three
cases the dinoflagellate cyst zonation schemes defined by Dutch scientists during the last
decade in bio- and magnetostratigraphically calibrated pelagic sequences of the
Mediterranean region, were successfully applied.
         1) The composite dinoflagellate cyst zonation of Wilpshaar et al. (1996), spanning the
latest Eocene-Early Miocene interval, was applied to the northern Tunisia Numidian Flysch,
whose basal portion is dated as earliest Oligocene (A. diktyoplokum-R. actinocoronata zones),
thus definitely older than previously inferred on the basis of scarce foraminiferal faunas.
Moreover, lateral relations instead of vertical ones are documented for the first time among
the Zouza, Kroumirie and Babouch members as a consequence of the role played by lateral
variations of sedimentary facies during the Oligocene and the Early Miocene.
         2) All the key events defining the four dinoflagellate cyst zones established by
Brinkhuis & Biffi (1993) in the lowermost Oligocene at the Massignano section (GSSP of the
Eocene/Oligocene boundary) were recorded in the Tusa Tuffite Formation of southern Italy.
Here calcareous nannofossils provide perfectly consistent information. Therefore, younger
ages, questionably inferred by some workers on the basis of poor foraminiferal assemblages,
have to be rejected. A regional correlation is drawn with other circum-Mediterranean Lower
Oligocene volcaniclastic turbidites, supporting the existence at that time of a unique volcanic
arc in the Alps/Apennines orogenic system.
         3) Exceptionally rich and well preserved palynological assemblages allowed for the
first time the precise age assessment of the Monte Soro Flysch of Sicily. The zonation
scheme established by Leereveld (1997) for the Lower Cretaceous of the western
Mediterranean is proved as a valid reference for the stratigraphic interpretation of the
dinoflagellate distribution in this unit.
DINOFLAGELLATE BIOSTRATIGRAPHY AND BENTHIC
FORAMINIFERS FROM THE RUPELIAN/CHATTIAN
BOUNDARY IN NW BELGIUM: TOOLS TO EXPORT THE
STAGE BOUNDARY OUT OF THE NORTH SEA BASIN?

S. VAN SIMAEYS, E. DE MAN
University of Leuven, Lab Stratigraphy, Redingenstraat 16, 3000 Leuven, B
H. BRINKHUIS
University of Utrecht, Lab Palaeobotany and Palynology, Budapestlaan 4, 3584 CD Utrecht,
NL

In order to define a suitable Global Stratotype and Section Point (GSSP) for the
Rupelian/Chattian, or Lower/Upper Oligocene boundary, it is primordial to recognize and
characterize biotic change associated with the unit-stratotypes, both defined in the southern
North Sea Basin. The Rupelian was defined by Dumont (1849) based on the Boom Clay
outcrops along the rivers Scheldt and Rupel in NW-Belgium; Anderson et al. (1971) selected
the Doberg near Bünde (Westfalen, Germany) as Neo-stratotype for the Chattian Stage.
         Currently, the Rupel/Chattian boundary based on the LAD of Chiloguembelina
cubensis at the top of planktonic foraminifer Zone P21 a, is considered to fall within
magnetochron C10n.1n, at ~28,5 Ma (Berggren et al., 1995).
         As clarified in Berggren et al. (1995) the Cenozoic time scale integrates an extensive
DSDP/ODP record of planktonic foraminifera and calcareous nannofossil biostratigraphy from
relative stable marine environments at low-latitudes. Because of the mid high-latitude position
of the North Sea Basin, and notably its enclosed palaeogeography, calcareous microfossil
correlations with international zonation schemes appear problematic for the critical interval.
Nevertheless, notably benthic foraminifers are quite useful for regional correlation. The earliest
layer of the Chattian sequence is locally known as the Asterigerina Horizon, named after the
bloom of this benthic foraminifer, and the FAD of Elphidium subnodosum and Protelphidium
roemeri (Gramann & Spiegler, 1986).
         Dinoflagellates seem to be less affected by latitudinal variations and occur in shallow
as well as in deep marine settings. A selection of dinoflagellate events from the upper part of
the Rupelian type locality, compared with the results of ongoing studies on sections from the
same interval in central Italy (OLIS project) allow detailed interregional correlation.
         From geophysical investigations of several boreholes in the north of Belgium
(Vandenberghe et al., 2001) it became clear that twice as much Boom clay is present in the
Campine subsoil, of which only the lower half corresponds with the outcrop section, studied on
dinoflagellates by Stover and Hardenbol (1994).
         The cored Weelde and Mol-1 boreholes cut through this unstudied upper part of the
Boom clay and were sampled in such way that our lowermost samples clearly overlap with the
topmost samples of Stover and Hardenbol (1994). Besides we also investigated the Late
Oligocene Voort sands and restudied the Chattian type material from the Doberg section.
         In the studied boreholes the Asterigerina Horizon is encountered; this level coincides
with the first occurrences of the dinocysts Pentadinium imaginatum, Artemisiocysta
cladodichotoma and Svalbardella sp. Shortly above this interval Apteodinium emslandense
has its first occurrence and Achilleodinium biformoides its last. The first occurrence of
Distatodinium biffii is well below the Asterigerina Horizon. These preliminary results match the
available data from the Tönisberg profile, northwest Germany (Benedek, 1972). Some of
these species may have the potential to be interregional markers and will play an import role in
the discussion whether the planktonic foraminifer Chiloguembelina cubensis does or does not
coincides with the base of the Chattian Stage?
PROGRESS IN MODELLING THE JURASSIC – CRETACEOUS
BOUNDARY USING PALYNODATA AND PALYNOPLOT

J.M. WHITE
Natural Resources Canada, Geological Survey of Canada, Calgary, Alberta, T2L 2A7

An experimental model of the palynological record of the Jurassic-Cretaceous boundary was
made using palynomorph occurrence records from Palynodata, a global palynological
database abstracting taxon, age and locality records from over 20,000 pieces of literature. A
taxon‘s distribution can be visualized by Palynoplot software, which bins and plots literature
records by time and modern latitude, yielding an approximation of the ―real‖ time/space
distribution of the fossil. Plots reveal temporal and latitudinal distribution patterns, as well as
potential taxonomic and data problems, such as outliers and inconsistent taxonomy. The
concentration of palynological studies in northern mid- latitudes, especially Europe, is evident.
Hence, patterns are weighted to the standards of those areas.
           Genera were chosen for the experiment because: there is more agreement amongst
palynologists about the characteristics of these genera than their species; the data are more
abundant, hence less noisy; and working with few taxa greatly simplifies the interpretation.
Citation abundance results are a ―consensus view‖, reflecting both population central tendency
and variation in the distribution of a taxon. This differs from and complements the ―type
section‖ view. Genera which are recognized as showing useful patterns of change through
Late Jurassic and Early Cretaceous time are Appendicisporites, Cicatricosisporites,
Contignisporites,     Crassitudisporites,   Impardecispora,      Ischyosporites,     Klukisporites,
Pilosisporites and Trilobosporites.
           Many genus plots show abrupt increases in abundance from the Jurassic to the
Cretaceous. Without evidence of rapid environmental change, one might anticipate a more
gradual transition. Hence, the abruptness of the change may be an artifact of the nature of
biostratigraphic inference. The ―real‖ J-K boundary may be somewhere in what is recorded as
Early Cretaceous.
           The northern mid-latitude dominance in study density makes it difficult to compare
patterns amongst genera in the time/latitude matrix. Comparison is facilitated by converting
each of the selected genera to a proportion of their sum for each time/latitude bin. As
proportions, the data are comparable between genera. The zones of higher data density
become areas of higher confidence. The proportional data can be visualized using GIS
software, which facilitates pattern recognition. Plots show that the ratio Appendicisporites +
Cicatricosisporites/ Klukisporites + Ischyosporites increases across the boundary. These
results are promising but need refinement. Could this or other ratios be used to provide a
palynostratigraphic standard for the Jurassic-Cretaceous transition? Could they be calibrated
by comparing the results with data from reference sections?
DIVERSITY IN MORPHOLOGY AND FUNCTION OF SPORES
FROM THE EMSIAN (LOWER DEVONIAN)
V. WILDE, R. BROCKE
Forschungsinstitut Senckenberg, Palaeobotanik, Senckenberganlage 25, 60325
Frankfurt/Main, Germany
W. RIEGEL
Göttinger Zentrum Geowissenschaften, Geobiologie, Goldschmidtstraße 3, 37077 Göttingen,
Germany

Associations of spores from the Emsian (Lower Devonian) and lowermost Eifelian (Middle
Devonian) of the Eifel Hills and the Middle Rhine area (Rheinisches Schiefergebirge,
Germany) have been studied palynologically. Due to the high degree of thermal maturity in the
organic matter from the study area, IR microscopy was successfully applied. Special attention
was paid to trends in the evolution of spore morphology and their potential functional meaning.
         Spores around the Lower/Upper Emsian boundary are still characterized by
comparatively small size and simple sculpture, whereas size and morphological diversification
increase significantly within the Upper Emsian and into the Eifelian.
         Most obvious trends are:
         1. A considerable increase in size in some of the taxa which may be related to
heterospory.
         2. An increase in complexity of ornamentation and exine thickness, possibly related to
mechanical resistance to transport/distribution or protection against drying up.
         3. Evolution of saccus-like structures, potentially related to aerial transport and/or
incipient gymnospermy.
         Altogether, these trends may have been related to major steps in the evolutionary
diversification among early land plants throughout the Emsian as reflected by palynological
results from the Rheinisches Schiefergebirge.
FORTIES FIELD: THE APPLICATION OF BIOSTRATIGRAPHY
TO A MATURE FIELD
G. WILLIAMS
GeoStrat Ltd., Dalziel Street, Motherwell ML1 1PJ, Scotland, UK
S.N.J. PAYNE, R. ANDERTON
BP Exploration Operating Company, Farburn Industrial Estate, Dyce, Aberdeen AB21 7PB,
Scotland, UK

Biostratigraphic studies have been carried out on the Forties Field throughout the field life.
The current study has taken this work forward with extensive new palynological analyses and
a change in emphasis from the Forties Main Sand that has dominated earlier stratigraphic
interpretation, to the younger sands in the upper part of the Forties Sandstone Member where
much of the remaining hydrocarbons are to be found.
          The approach taken in this study emphasizes a holistic approach to the taxonomic
groups used, using dinocysts, prasinophycean algae, pteridophyte miospores, angiosperm
pollen, reworking events and taxa of unknown affinity.
          A total of forty-one bioevents have been recognised from the dataset of which eleven
are considered to be the most reliable. These events have been recognised elsewhere in the
Forties fan system, e.g. Arbroath, Montrose.
          These events reflect a combination of extinctions, inceptions, acmes, subregional
palaeoenvironmental changes and local palaeoenvironmental events. These latter events
reflect the affects of a number of drivers including tectonism, flooding events, climate and the
progradation of the fluviodeltaic system which fed sediment into the Forties fan. These
relationships are interpreted in relation to regional sequence stratigraphic events.
          The stratigraphic resolution achieved has been integrated into seismic interpretation
and sedimentological interpretation to constrain the architecture of sands within the upper part
of the Forties Sandstone Member.
          This greater understanding has allowed better definition of remaining unproduced
hydrocarbons and provided a robust biostratigraphic scheme to assist in the drilling of infill
wells to tap these accumulations.
NON-ACID WELLSITE PALYNOLOGY: WIDENING
OPPORTUNITIES

G. WILLIAMS, P. WATSON
GeoStrat Ltd., Dalziel Street, Motherwell, Lanarkshire ML1 1JP, Scotland, UK
S.N.J. PAYNE
BP Exploration Operating Company, Farburn Industrial Estate, Dyce, Aberdeen AB21 7PB,
Scotland, UK
R. DYER
GeoStrat Ltd., Dalziel Street, Motherwell, Lanarkshire ML1 1JP, Scotland, UK
D.F. EWEN
BP Exploration Operating Company, Farburn Industrial Estate, Dyce, Aberdeen AB21 7PB,
Scotland, UK

Wellsite palynology is an established geoscientific tool, which involves the ‗real time‘
preparation and analysis of samples from the subsurface. Analysis of the palynomorphs in
these samples during drilling is used to identify the location of the drill bit in the geological
succession, critical for reservoir prediction, enabling crucial decisions including biosteering,
casing, coring and terminal depth calls to be made.
         Until recently extraction of the palynomorphs was only considered possible with the
use of highly toxic and hazardous chemicals (e.g. hydrofluoric acid) and technical support in a
mobile laboratory, resulting in high costs, logistical problems and HSE risk. Developments
made by GeoStrat Ltd. have removed the bulk of the chemical component in the sample
processing and allow a primarily mechanical extraction technique to be employed at the
wellsite, a major breakthrough, which reduces cost and logistical problems and virtually
eliminates any chemical HSE risk. As a result, the application of wellsite palynology has
expanded, operational costs at wellsite have been reduced, the dependence on a limited
market place for the hire of specialised laboratory equipment is eliminated and the global
reach and potential of this technique is enhanced.
         The technique has been used successfully at wellsite for sediments of Tertiary to
Middle Jurassic age, whilst laboratory testing has shown a wide geographic and age
applicability.
         BP has formed a strategic alliance with GeoStrat to use this technique and has
applied it to over 30 wells in offshore UK and Norway. The proportion of wellsite palynology
now undertaken utilising this technique within BP, in the UK and Norwegian offshore, has risen
to over 30% and will continue to rise.
         Examples of the application of the technique will be given, with particular emphasis on
horizontal biosteering, maximising mature field recoverable reserves and areas with logistical
limitations.
A HIGH RESOLUTION PALYNOSTRATIGRAPHIC
FRAMEWORK FOR THE FLUVIAL-LACUSTRINE
PATCHAWARRA FORMATION, COOPER BASIN, SOUTH
AUSTRALIA

G.R. WOOD, P.C. STRONG
Santos Limited, 91 King William Street, Adelaide, South Australia 5000

Fluvial-lacustrine reservoirs in coal-bearing strata provide a particular challenge for reservoir
characterisation because of the dominance of coal on the seismic signature and the highly
variable reservoir geometry, quality and stratigraphic connectivity. The development of flow
unit scale geological models for the fluvial gas reservoirs in the Permian Patchawarra
Formation of the Central Australian Cooper Basin are critical to minimise the perceived
reservoir risks of these relatively deep targets. A multidisciplinary team was formed to
integrate recently acquired 2D and 3D seismic data to the geology using high-resolution
sequence stratigraphic concepts to constrain depositional environments and thus provide a
better tool for predicting reservoir distribution. An improved model required the construction of
a robust regional chronostratigraphic framework as a starting point, constrained where
possible by palynostratigraphic control. The framework has been developed by identifying key
surfaces, primarily unconformities, regional lacustrine flooding surfaces represented by high
gamma ray shales, or climatically and tectonically controlled periods of clastic shutdown
represented by regionally extensive coal. It was important to define the regional
chronostratigraphic significance of these surfaces in order to extend the scheme more
confidently to areas of high heat flow where palynostratigraphic control was poor.
         The chronostratigraphic framework utilised has been built around improvements to
the palynostratigraphic scheme for Eastern Australia together with the definition of an
additional series of events specific for the Cooper Basin. This refined Cooper Basin
spore/pollen event stratigraphy is of sufficient resolution to provide control for the twelve
regionally correlatable markers and eighteen local horizons. Two major unconformities within
the Patchawarra Formation divide the section into three mega sequences. The recognition of
these tectonically enhanced sequence boundaries in conjunction with the higher resolution
palynostratigraphic control has permitted the delineation and correlation of
chronostratigraphically significant surfaces with confidence.
         The chronostratigraphic framework defined has allowed detailed palaeogeographic
mapping to be carried out at flow unit scale. For specific horizons, palaeogeographic
reconstructions were produced by an iterative process between the detailed log analysis,
sedimentology and fine-scaled seismic mapping. These maps are drawn with the guiding
control of syn-depositional structural features and net/gross trends, using structure and
isochron maps from the seismic interpretation.
PALYNOLOGICAL ANALYSIS OF MYOTRAGUS BALEARICUS
COPROLITES – THE EXTINCTION OF ANIMAL AND VEGETAL
SPECIES DURING THE HOLOCENE IN THE BALEARIC
ISLANDS (SPAIN)

R. YLL, R. PÉREZ-OBIOL
Departament de Biologia Animal, Biologia Vegetal i Ecologia, Unitat de Botànica, Universitat
Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
J.A. ALCOVER
Institut Mediterrani d'Estudis Avançats (CSIC-UIB), Cta de Valldemossa km 7,5, 07071 Ciutat
de Mallorca, Balears, Spain

The Balearic Islands are located in a very critical biogeographic position with respect to the
oscillations that dominated the climate during the Quaternary. The study of the evolution of the
landscape in these islands shows that the processes of change have been more evident in
comparison with the continent. A radical change of the landscape registered during the
Holocene implied the medium term disappearance of some vegetal and animal species. The
extinction of Hypnomys morpheus, Nesiotites hidalgo and, specially, of Myotragus balearicus
are well documented. Myotragus balearicus was a ruminant exclusive of the Balearic Islands.
The first human inhabitants settled in the Balearic Islands coexisted with Myotragus until the
species became extinct, at about 4,000 years ago. The unusual morphology of Myotragus
balearicus has originated speculations on its diet.
          The fact that Myotragus balearicus lived under insular conditions implies that
particular adaptations to the pre-human environments have been done. Likewise, Myotragus
balearicus has been played an important role within the insular ecosystems of the Balearic
Islands and could be related with the evolution and the transformation of the Balearic flora.
          Coprolites of Myotragus balearicus have been collected during several excavation
campaigns and palynological analyses were carried out. Pollen analyses reveal that Buxus
balearica (a toxic plant) was involved in the habitual diet of Myotragus balearicus, being a
source of great importance. Buxus balearica was an abundant pant in the landscape until the
mid Holocene and, afterwards, reduced its presence dramatically. This fact could have been
related with the cause of the reduction of its presence in the Balearic Islands. It is difficult to
assign a simple causal relation between the extinction of Myotragus balearicus and this plant.
In addition, this disappearance is produced synchronically with the abrupt climatic change
registered in the Mediterranean during the V millennium BP and with the expansion of the
human presence in the Balearic Islands. These considerations open a debate that must
consider the relation between this extinction and their explanation from climatic or anthropic
causes.

				
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