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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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