OCTOBER
2001
Issue 71
MEGUMA GOLD DEPOSITS, NOVA SCOTIA: OVERVIEW OF
PAST WORK WITH IMPLICATIONS FOR FUTURE WORK
Daniel J. Kontak, Richard J. Horne and eastern North America during the Acadian shaped folds (Fig. 2)and metamorphosed to
Paul K. Smith Orogeny at ca. 395 Ma along the transcurrent greenschist-amphibolite facies. A late brittle-
Cobequid-Chedabucto Fault (Fig. 1). The base- ductile reactivation of the fold belt at ca. 375
Nova Scotia Department of Natural ment rocks to the MT, consisting of high-grade Ma is recorded by flexural-slip folding of the
Resources, P.O. Box 698, Halifax, para- and orthogneiss with Ar-Ar amphibole metasedimentary rocks, as represented by bed-
Nova Scotia B3J 2T9 and mica ages of ca. 375 Ma, are present in the ding-parallel movement horizons (Fig. 3a;
Liscomb Complex (LC in Fig. 1), a structural Horne and Culshaw, 2001). The Meguma
window within the central MT and as xenoliths Group was intruded by ca. 370 Ma meta- to
INTRODUCTION within 372 Ma shoshonitic lamprophyres (i.e., peraluminous, crust-derived granitic plutons (e.
The Lower Paleozoic Meguma Group of Nova Weekend dykes in Fig. 1) along the eastern g.,South Mountain Batholith, Fig. 1). The offset
Scotia, host to 60 past producing gold districts shore of the MT. of cordierite in hornfels along fold-related
with historical production of 1.2 million oz., is The Meguma Group consists of the meta- movement horizons (Horne and Culshaw, 2001)
considered one of the classic areas of turbidite- sandstone-rich Goldenville Formation and over- and the presence of a folded magnetic fabric
hosted gold mineralization (Kontak et al., 1990; lying slate-rich Halifax Formation. The Me- within the 370 Ma granites (Benn et al., 1997)
Ryan and Smith, 1998). Most mining occurred guma Group was deformed into NE-SW to N-S suggests the granites are late syntectonic.
over a 60-year period between 1860-1920, but trending, tight- to open-, chevron- to box-
interest was rejuvenated during exploration in
the 1980's with reassessment of many former 373 B D
districts and some new discoveries (e.g., Tou- 363 F M S FH
374 C LC CH
quoy Zone at Moose River, North Brookfield 370 W G
CCFS
disseminated zone, faulted off extension at the
Dufferin deposit, Fig. 1). In addition to renewed NP
exploration, numerous geoscience studies which NB
366 U SH
were undertaken generated abundant new infor-
mation concerning the genesis of the deposits
SM B WD
MB
(e.g., see Sangster, 1990). Below we summarize D
results of over a century of mining and explora- H a lifa x
374 T T R IA S S IC T O JU R A S S IC
tion along with results of recent research and sedim entary and volcanic rocks
comment on the relevance of such efforts for 375 M R L ATE D E V O N IA N T O C A R B ON IFE R O U S
future development. sedim entary rocks
376 O M ID D L E D E V O N IA N
granitoid rocks
REGIONAL GEOLOGICAL SETTING N ew
65
o
P.E .I.
E A R LY SIL U R IAN T O EA R LY D E V O N IA N
metasedimentary and
The gold deposits are hosted by Cambro- SP
B runs w ic k metavolcanic rocks
E A R LY SIL U R IAN
Ordovician metaturbidites of the Meguma A VA L O N T E R R A N E granitoid rocks
Group that underlay most of the Meguma Ter- M E G U M A TE R R A N E
ti a
45
o
C A M B R IA N TO E A R LY O R D O V IC IA N
S co
rane (MT) of the Canadian Appalachians (Fig. ov
a H alifa x
H alifax F orm ation M egu m a
N G r ou p
1). The MT was accreted to the Avalon Zone of 0 100
G o lden ville F orm ation
km faults
,QVLGH WKLV LVVXH Fig. 1. Outline of the geology of the Meguma Terrane, southern Nova Scotia, and location of
the area in Maritime Canada (inset map). The location of Meguma gold deposits referred to in
Editors’ Message the text are identified along with 40Ar/39Ar ages obtained on vein minerals in several deposits.
Conference Report Deposits from west to east are: North Brookfield (NB), The Ovens (O),West Gore (WG),
Moose River (including Touquoy Zone; MR), Caribou (C), Tangier (T), Beaver Dam (BD),
Any Nominations? Dufferin (D), Fifteen Mile Stream (FMS), Cochrane Hill (CH), Forest Hill (FH), Upper Seal
Harbour (USH). Other abbreviations are for the South Mountain Batholith (SMB), Shelburne
Irish-type deposits pluton (SP), Musquodoboit Batholith (MB), Liscomb Complex (LC), Weekend Dykes (WD)
and Cobequid-Chedabucto Fault System (CCFS).
Sullivan farewell (Continued on page 4)
0,1( 5$/ '(32 6,7 6 ',9, 6,21 (;(&87,9 ( /, 67
0,1(5 '(326 ',9,6 ;(&87,9( /,6 MDD Goals and Objectives
Chairperson: Steve Piercey The Gangue is published quarterly by the Min-
Dept. of Earth Sciences, Laurentian University, Ramsey Lake Road, Sudbury, ON eral Deposits Division of GAC and is distrib-
P3E 2C6; Tel: (705) 675-1151 ext. 2364; FAX: (705) 675-4898; uted to its members. The Mineral Deposits Di-
email: spiercey@nickel.laurentian.ca vision of the Geological Association of Canada
is Canada’s foremost society for promoting the
study of mineral deposits by supporting local
Past Chairperson: Andrew Conly
Dept. of Geology, Univ. of Toronto, 22 Russell St. Toronto, ON M5S 3B1; Tel: and national meetings, symposia, short
(416) 978-0657; FAX: (416) 978-3938; email: aconly@quartz.geology.utoronto.ca courses, and field trips. We sponsor the publi-
cation of research relating to ore deposits and
metallogeny, and recognize the contributions
Vice Chairperson: Frank Santaguida of outstanding Canadian economic geologists
Falconbridge Ltd.,, Exploration office, Kidd Creek Minesite, P.O. Box 1140, Tim- by annually awarding the Duncan Derry and
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Tel: (604) 947-0038; Fax: (604) 947-0038
The objective of this newsletter is primarily to
or, Arizona, Tel/Fax: (602) 423-1006; email: bobcat@direct.ca
provide a forum for members and other profes-
sionals to voice new ideas, describe interesting
Publications: Dirk Tempelman-Kluit mineral occurrences or expound on deposit
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ferences, reprints of presentations to compa-
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Medals Committee: Dan Marshall David Lentz – THE GANGUE
Dept. of Earth Sciences, Simon Fraser Univ., Vancouver, BC Dept. of Geology, Univ. of New Brunswick,
Tel: (604) 291-5474; Fax: (604) 291-4198; email: marshall@sfu.ca Fredericton, NB E3B 5A3
Email: dlentz@unb.ca
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http://mdd.harbour.com/ N.B. Geological Survey, PO Box 50,
495 Riverside Drive, Bathurst, NB E2A 3Z1
Email: Steve.McCutcheon@gnb.ca
October 2001 – Gangue No. 71
MDD DIRECTORS Editor’s Message
• Georges Beaudoin (2000-2003)
Dept. de geologie et de genie geologique, Geological Survey on Verge of Extinction?
l’Universite Laval, Quebec City, QC; Tel:
(418) 656-3141; Fax: (418) 656-7339; email: The provincial government of British Columbia has announced that
beaudoin@ggl.ulaval.ca its Geological Survey (BCGS) will be dismantled over the next cou-
ple of years, presumably because it is perceived to have little value
• Mike Lesher (2000-2003) to the local populace, unlike health care, and therefore will not be
Dept. of Earth Sciences, MERC, Laurentian missed by the average voter on the streets of Vancouver. The voter
Univ., Sudbury, ON; Tel: (705) 675-1151 can be forgiven for not knowing how important the BCGS is to the
ext 2276; Fax: (705) 673-6508; email: Province because the mineral industry has been the main benefici-
lesher@@sympatico.ca ary of the BCGS’s work.
• Tom Lane (2000-2003)
Consultant., Toronto, ON
Most people in the mineral industry know the value of the BCGS’s
email: tom.lane@sympatico.ca geoscience database and in-house expertise, especially those who
have worked in jurisdictions where they do not exist. Such a data-
• Dan Marshall (1999-2002) base is generally the starting point for mineral exploration pro-
Dept. of Earth Sciences, Simon Fraser Univ., grams, allowing explorationists to test models and build on what
Vancouver, BC; Tel: (604) 291-5474; Fax: others have done before them. In other words, it permits industry to
(604) 291-4198; email: marshall@sfu.ca spend exploration dollars wisely in areas that have the best mineral
potential. Historically, this has been the raison d’être for provincial
• Dave Peck (1999-2002) geological surveys to exist but it should not be the only reason.
Falconbridge Exploration Ltd.
21C Murray Park Road, Winnipeg, MB; The BCGS’s geoscience database and expertise are of value to
Tel.: (204) 888-9860; Fax: (204) 885-4152; non-industry users to help fill societal needs, e.g. groundwater pro-
Email: dpeck@falconbridge.com
tection and land-use planning, although few in government recog-
nise this fact. Politicians and senior bureaucrats need to under-
• Jeremy Richards (1999-2002)
Dept. of Earth Sciences, Univ. of Alberta,
stand that a good geoscience database is like the foundation under
Edmonton, AB; Tel: (403) 492-3430; Fax: a house; it is not obvious, but without it the house cannot stand.
(403) 492-2030; This begs the question, what happens to the existing geoscience
email: Jeremy.Richards@ualberta.ca database when the BCGS is eliminated? Will it go to the govern-
ment paper shredder or disappear into digital doo-doo?
• Derek Wilton (1999-2002)
Dept. of Earth Sciences, Memorial Univ. of Imagine where Canada would be if other provinces were to decide
Nfld., St. John’s, NF; Tel: (709) 737-8389; to follow BC’s example. In the absence of Provincial Surveys,
Fax: (709) 737-2589;email: dwil-
would the Geological Survey of Canada maintain databases for
ton@sparky2.esd.mun.ca
each Province? Could the private sector fill the void? We don’t
• Bob Friesen (1998-2001) think so! Therefore, we urge you to write to the Premier Gordon
Teck Exploration, Kamloops, BC; Tel: (250) Campbell of British Columbia to voice your concerns about the
372-0032; Fax: (250) 372-1285; planned extinction of the BCGS. You can e-mail him
email: gfriesen@wkpowerlink.com (premier@gov.bc.ca) or send a real letter to: Office of the Premier,
Parliament Buildings, Victoria, BC, V8V 1X4.
• Mike Sweeney (1998-2001)
Falconbridge Exploration, Falconbridge, All the best to you & your families this coming Holiday Season
ON; Tel: (705) 693-2761 ext. 3655; Fax: and into the New Year.
(705) 699-3600; email:
Mike_Sweeney@sudbury.falconbridge.com
Steve McCutcheon
Dave Lentz
October 2001 – Gangue No. 71 3
MEGUMA GOLD DEPOSITS
Introduction 6RXWK 8QLDFNH *ROG 'LVWULFW NP
The Meguma gold deposits (MGD) include a variety of auriferous
quartz-vein style and disseminated mineralization within the Meguma
Group metasedimentary rocks. Although there is diversity with respect
to some features (vein geometry, mineralogy, alteration, grade), in gen-
eral there is a first order similarity of deposits and we focus on these
features below. However, some common misconceptions about the de- 1: 6(
posits are first noted: (1) they are all saddle reef-type deposits. In fact,
such deposits sensu stricto are rare (e.g., Dufferin, Upper Seal Harbour;
Fig. 2. Cross section of the South Uniacke gold district, Nova Scotia
see Malcolm, 1929). Deposits are dominated by simple vein types of
illustrating the preference of quartz veins for the hinge area of anti-
bedding- concordant and -discordant nature with veins concentrated on
clines. Also note the concentration of veins on the steeper limb area.
limb areas of antiformal structures; (2) wall-rock alteration is absent. In
fact, there is wall rock alteration marginal to veins, with carbonatization
and sulphidization the most common (see below). However, alteration beds; (2) are <1 cm to 10's cm thick (Fig. 4c, d e, f,); (3) have lateral and
can be inconsistent in its development; (3) all auriferous veins are char- vertical continuity of 100's m (Malcolm, 1929; our observations); and (4)
acterized by crack-seal textures. However, these classic textures are of commonly buckled in fold hinges (Fig. 4c), and more rarely on limbs.
minor occurrence and are absent in most veins; and (4) deposits are con- Discordant veins, showing variable degrees of strain, include: (1) steep
fined to the Goldenville Formation and, therefore, there is a stratigraphic veins or conjugate-vein sets, which are roughly parallel to the ac plane
control. In fact, the present distribution of MGD more likely reflects the of the fold (Fig. 3a); and (2) shallow en echelon veins that are related to
current structural level of exposure, with the lower Goldenville Forma- bedding-parallel shear. Mutual cross cutting relationships among all vein
tion coring anticlines where gold deposits occur. In addition, we empha- types indicate synchronous timing of vein emplacement (Fig. 3a).
size that several MGD do indeed occur within the Halifax Formation (e.
g., The Ovens, West Gore, Caribou).
General features of deposits and sub-types
The MGD occur throughout the MT without preference for metamorphic
grade. Although the majority of deposits occur within the Goldenville
Formation, the metasandstone-rich lower part of the Meguma Group
stratigraphy, as noted above this is a structural control. Two general de-
posit types occur, namely: (1) quartz-vein hosted mineralization and (2)
vein-poor or vein-free mineralization, which is also referred to as dis-
seminated mineralization, that has also been recognized recently within
other turbidite-hosted gold belts (e.g., Christie et al., 2000). Features
common to both these deposit types include: (1) variably developed wall
rock alteration with development of secondary quartz, carbonate, Fe-
sulphides (py, po, aspy; Fig. 4h, i), tourmaline, biotite and white mica;
(2) occurrence within a mixed stratigraphy of metasandstone, metasilt-
stone and slate (Fig. 4a) with variable amounts of primary Fe-sulphide,
carbonate and organic carbon in the rocks; (3) proximity to anticlinal
structures or domes, but deposits are preferentially within the steeper,
overturned limb areas (Fig. 2); and (4) presence of porphyroblastic min-
erals or aggregates (bt, ms, carb, oxides; informally referred to as
oikocrysts) on cleavage surfaces with a steep, down-dip stretching linea-
tion (Fig. 4g). These features are interpreted to reflect subvertical exten-
sion late in the deformation history.
Vein-rich deposits
Deposits characterized by the presence of quartz veining include bed-
ding-concordant (Fig. 4d), saddle reef (Fig. 4c), stockwork (Fig. 4j), and
fissure vein types and, although several vein types are common within
single deposits, one vein type usually dominates. The deposits generally
occur near hinge zones of anticlines, commonly domes, and it is empha-
sized that away from these areas the abundance of quartz veins dimin-
ishes rapidly (Figs. 2, 3b). Thus, an important first order observation is Fig. 3. (a) Veins in metasiltstone and shale on the northern limb of The
that vein emplacement was coincident with processes focused within Oven Anticline (see Horne and Culshaw, 2001). Photo shows a set of
fold hinges which must have existed prior to veining. Historically, the relatively early conjugate discordant veins (CV) that are offset by
most important deposit type is where bedding-concordant veins domi- movement on flexural-slip horizons (indicated by dashed lines) con-
nate (Malcolm, 1929; see Ryan and Smith, 1998 for review). Where taining flexural-slip veins (FSV). The latest veining is recorded by the
veins are dominantly of bedding-concordant type (also bedding parallel), discordant veins (DV) in left of photo that correspond to the ac plane
discordant veins (fissure, stockwork, conjugate) may also be present, of the fold. (b) Underground photo mosaic of bedding-concordant
albeit in much lesser amounts. Features of the concordant veins include: veins in the hinge of the anticline hosting the Upper Seal Harbour gold
(1) preferentially occur at slate-sandstone contacts or within the slate district.
October 2001 – Gangue No. 71
Fig. 4. Photographs illus-
trating some features of
Meguma gold deposits.
(a)Typical interbedded
metasiltstone and shale in
southern limb of The
Ovens Anticline. (b)
Bedding-concordant vein
from Tangier showing
composite texture of
white crystalline quartz
and earlier dark quartz.
Note that coarse nuggety
gold (outlined in dashed
line) occurs in the later,
white quartz that is lo-
cally vuggy. (c) Veins (1-
3 cm thick) in the hinge
area of The Ovens Anti-
cline. Buckling of some
veins is restricted to the
hinge area, interpreted to
reflect local layer-parallel
shortening during flex-
ural-slip fold growth and
vein emplacement. (d)
Folded, bedding-
concordant vein contain-
ing disseminated pyrite
on the south limb of Bea-
ver Dam Anticline. Vein
is ca. 10 cm thick. (e)
Bedding-concordant vein
at Beaver Dam with com-
ponent of wall rock in-
clusions and dark, lami-
nated quartz with crack
seal texture. Vein is ca.
0.3 m thick.(f) Sample of
the Marker Vein at Tang-
ier photographed on the
ore pile. Note presence of
crack-seal like texture cut
by later white, crystalline
quartz. Gold in this vein
occurs in the white
quartz. (g) Subvertical
lineations of retrograded
andalusite grains in
cleavage plane located at
west end of Mooseland
gold district near 370 Ma
Musquodoboit Batholith.
(h) Arsenopyrite (1-2 cm
size grains) disseminated
in bleached metasand-
stone in Port Dufferin/
Salmon River gold dis-
trict. Note the thin discor-
dant vein with Fe carbon-
ate in bottom of photo. (i) Arsenopyrite veins cutting discordant quartz vein in Papke Zone of the Beaver Dam gold deposit. Quartz vein is ca. 0.3
m thick. (J) Intense development of stockwork vein system in underground workings of the Caribou gold deposit. Ladder is ca. 0.6 m wide.
O ctober 2001 – G angue N o. 71 5
The veins are clearly composite in nature and include a white, crys- observations at a few select localities, Horne and Culshaw (2001) dem-
talline quartz and a dark grey, laminated quartz (i.e., crack-seal type tex- onstrated that bedding-concordant and discordant (i.e., conjugate type)
ture), with the former type dominant (ca. $90-95%; Figs. 4e, f, 5a, b). vein emplacement is related to flexural-slip folding during a late-stage
Detailed field and petrographic observations indicate: (1) the laminated tightening of the regional-scale folds (Fig. 3a). Mutual cross-cutting rela-
quartz occurs mainly within bedding-concordant veins and rarely discor- tionships of concordant and discordant vein types indicates synchroneity
dant types; (2) the white quartz cross cuts the dark, laminated quartz of vein formation. In addition, examination of quartz vein formation
(Fig. 4f); (3) in the laminated quartz there is a textural continuum from within contact aureoles of the 370 Ma granites indicates that movement
ribbon-type laminations (i.e., wall rock septa, Fig. ) to crack seal (i.e., horizons active during vein formation also offset cordierite hornfels, thus
new mineral growth); (4) there are distinct textural features (Fig. 5e, f) some veining is constrained to ca. #370 Ma (i.e., age of granites) (Horne
indicating a replacement origin for some of the laminated quartz and and Culshaw, 2001). Based on observations at other gold districts
new mineral growth (Fig. 5d, e,). (Kontak et al., 1990) and ongoing work (Dufferin deposit), it appears
The veins are dominated by quartz, but there is a diverse suite of that most veining occurred late in the folding history.
40
additional mineralogy with two broad assemblages present, designated Ar/39Ar dating of hydrothermal vein minerals (amph, ms, bt) from
types 1 and 2 (abbreviations after Kretz, 1992): (1) qtz+cal+chl+alb+ms seven deposits in the eastern MT gave plateaus indicating apparent ages
(+ant/rt, tur, sch), and (2) qtz+bt+Ca-rich plg (+amph, tur, grt, kfs, ep, of 374 Ma to 363 Ma (Fig. 1). In one deposit (Beaver Dam), concordant
and, st, ap, ilm). Type 1 is the dominant assemblage within deposits, amph, ms and bt ages of ca. 370 Ma indicates rapid post crystallization
whereas type 2 is rare and is restricted to deposits proximal to granitic cooling following vein formation given the large range in blocking tem-
intrusions (e.g., Newhouse, 1936; Beaver Dam) or areas of high-grade peratures for these minerals (200oC). We also note that a comparison of
40
metamorphism (e.g., Cochrane Hill, Forest Hill). Type 2 assemblage is Ar/39Ar ages for slate samples from within ribbon-textured auriferous
commonly overprinted by Type 1 assemblages. Sulphide minerals (po, quartz veins versus hydrothermal micas in the same deposits (n=5) indi-
py, aspy, ccp, gn, sp, mo, stb) and Bi-Te-Ag-S phases are difficult to cate that whole rock ages are some 10-20 Ma older than the ages of vein
define paragenetically, but generally appear late in terms of vein forma- micas (Fig. 6; Kontak et al., 1998). These data are, therefore, consistent
tion. with structural observations that vein emplacement was late in the defor-
Gold occurs mostly as free grains in the white, crystalline quartz mational history and, furthermore, indicate that vein micas have not been
rather than the dark laminated quartz (Fig. 4b). Gold has a preference for reset by the granite intrusions since the whole rocks ages are not affected
vein:wall rock contacts or pelitic inclusions, and minor amounts occur in (cf. Sangster, 1990).
the immediate wall rock. Where gold occurs in sulphides, it is along
cross-cutting fractures. Gold chemistry is uniform with 6-10 wt. %Ag Nature of vein-forming fluids and source reservoirs
and rare electrum occurs with galena and Bi-Te-Ag-S phases. The only The nature of the vein-forming fluids are inferred from fluid inclusion
exception is the occurrence of Au-Sb and Au-Cu alloys at the West Gore and stable isotopic studies on vein mineralogy. Inherent in this approach,
Au-Sb deposit. however, is the assumption that gold deposition is cogenetic with the
Historical and recent mining has determined that higher-grade gold minerals being studied, since gold itself is not directly analyzed. We em-
mineralization is not uniformly distributed within veins, but instead oc- phasize this point because of the following: (1) gold distribution is er-
curs within ore shoots. The ore shoots represent secondary structures ratic within veins with the higher grades occurring within ore shoots; (2)
within the plane of the quartz vein or sheet. Examples of such structures coarse, nugget-type gold typically occurs in vuggy quartz (Fig. 4b) -
include: (1) a roll or minor fold in a quartz vein (e.g., Forest Hills), (2) does this indicate partial dissolution and in filling of the vein quartz.
intersection of a discordant vein with bedding-concordant vein (e.g, Lib- These two features together are interpreted to indicate that gold has been
bey Fissure at Brookfield), or (3) kink zone within a large discordant mobilized or upgraded and is not necessarily always cogenetic with the
vein (e.g., Caribou). Recognition of such features within a deposit is host. Important exceptions would be where Au-Cu and Au-Sb alloys
paramount to successful exploitation. coexist with chalcopyrite and stibnite mineralization (e.g., West Gore).
Fluid inclusions hosted by vein quartz and carbonate are uniform in
Vein-free deposits composition and textures among deposits and include the following: (1)
Several areas have been recognized as containing gold in vein-free parts two- and three phase (LH2O-LCO2-V) aqueous-carbonic inclusions (Fig.
of the stratigraphy, although generally within or near a typical quartz 7). The number of phases present depends on the density of the CO2
vein deposit (Ryan and Smith, 1998). Host rocks include shale (Touquoy phase, which can be highly variable within samples; (2) two-phase aque-
Zone at Moose River) or metasandstone (North Brookfield) and free ous inclusions, (3) three-phase aqueous (LH2O-V)-Halite inclusions; and
gold occurs in the matrix, but is commonly closely associated with Fe- (4) two-phase (LH2O-V) aqueous inclusions with abundant silicate inclu-
sulphides. The mineralized zones are characterized by enrichment in sions, which are exclusive to areas of crack-seal textured quartz (Fig. 5g,
disseminated sulphides, Ca-Fe carbonate and white mica. Gold grade is h). The important aspects of fluid inclusion thermometric work are: (1) a
generally in the 1-4 g/t range, but grab samples have yielded up to 134 g/ large range in Th of the CO2 component, thereby inferring a variation in
t. The most promising site is the Touquoy Zone at Moose River, where a CO2 density; (2) variation in the proportion of aqueous:carbonic phases
drill-indicated resource of 5.7 Mt of 2.2 g/t ore has been delineated. At in inclusions among deposit areas, also indicating a range for inclusion
North Brookfield anomalous concentrations of Fe, As, Cu, Ag, Zn, Pb densities (Fig. 7); (3) evidence of fluid unmixing. Although fluid unmix-
and W are associated with gold mineralization of 1.2 g/t. The mineraliza- ing is rarely evident, at the West Gore Au-Sb deposit the process was
tion at North Brookfield occurs as irregular- to spheroidal metal alloys pervasive. Collectively, the fluid inclusion data compare well with the
and native metals, and this unusual assemblage has also been recognized moderately saline, aqueous-carbonic fluid chemistry for other mesother-
within some of the classical vein-type MGD localities. The disseminated mal gold deposits. In addition, isochoric projections for MGD samples
style of mineralization also occurs within vein-type deposits, examples indicate large fluctuations in fluid pressure during vein formation (Fig.
being the Beaver Dam and Upper Seal Harbour deposits (Fig. 1). 7), as might be expected where hydraulic fracturing occurred. The range
in fluid pressure, commonly exceeding the lithostatic pressures by 1-2
Timing of quartz veining and mineralization kbars, compares with results for other lode gold deposits (e.g., Robert et
The timing of vein emplacement is inferred from structural relationships al., 1995).
and 40Ar/39Ar dating of hydrothermal vein minerals. Based on detailed Stable (S, C, O, D) and radiogenic (Sr, Pb) isotopic data are avail-
October 2001 – Gangue No. 71
able for many of the vein minerals of MGD. The light stable isotopic tourmaline) and Pb (sulphides) data also reflect interaction with the wall
data (S, C) are consistent with contributions from the Meguma Group rock, their signatures indicate a another source reservoir. In summary,
rocks, whereas the heavier isotopes (Sr, Pb) indicate other source reser- the isotopic data indicate derivation of vein fluids from the basement to
voirs, and O data are equivocal. For example, /34S data for Fe-sulphides the Meguma Group with subsequent interaction with the Meguma sedi-
show • 2-3‰ variation within a deposit (e.g., /34S at Beaver Dam = +9 to ments.
+12‰, n=42), but for all MGD deposits the range is from +10 to +30‰
and mimics the stratigraphic /34S trend, which reflects a Lower Paleo- GENETIC MODEL
zoic global anoxia event (Sangster, 1990). The carbonate /13C data are - The MGD occur throughout the MT and gold was mined from 60 known
20 ± 4‰(n=110) and indicate a reduced biogenic source of C, which is districts. However, these areas share many common first order features
likely sourced in the Meguma Group as graphite or carbonate. The /18O suggesting a similar process was responsible for their genesis. Thus, in
carbonate data vary from +12 to +27‰, but a primary range of +12 to terms of a genetic model for MGD the following points must be consid-
+15‰ is suggested from )quartz-carbonate fractionation. Quartz /18O ered: (1) veins are confined to fold hinges and adjacent steep limbs,
values range from +13 to +17‰, excluding the West Gore deposit (to which implies that fluids were focused into previously folded stratigra-
+19‰), and show a slight variation to heavier values when deposits are phy; (2) veins were emplaced during flexural-slip folding late in the
arranged stratigraphically from deepest to shallowest. Calculated folding history of the Meguma Group. Buckling of veins in fold hinges
/18Owater values (for 400oC) using 18O quartz and carbonate data are +8 to reflects layer-parallel shortening in hinge regions synchronous with flex-
+12‰. The *D data for fluids at two deposits (Beaver Dam, West Gore) ural-slip shear on limbs; (3) vein emplacement, as constrained by struc-
indicate values of -20 to -50‰. Collectively, the C, O and D data indi- tural observations and absolute dating to ca. 370 Ma, was in some cases
cate the vein fluid was of metamorphic nature and its signature reflects coincident with granite emplacement; (4) the vein-forming fluids are
interaction with Meguma Group wall rocks. Whereas the Sr (carbonate, exotic to the Meguma Group, but show variable amounts of interaction
Fig. 5. Features of crack-seal texture in samples from underground workings of the Caribou gold deposit and The Ovens gold district. (a) Bed-
ding-concordant vein with dark quartz columns in sea of white crystalline quartz. This sample is similar to that discussed by Henderson et al.
(1990). (b) Vein sample in Figure 5a cut parallel to vein:wall rock contact showing pseudo-hexagonal shape of the dark “quartz” columns. (c)
Thin section cut parallel to long axes of the dark columns in Figure 5a showing abundant, thin lamellae. Note that there is a lack of lateral conti-
nuity to some of the lamellae. (d) Back scattered electron (BSE) image of lamella in crack-seal textured quartz from The Ovens. The lamella
consist of euhedral quartz with considerable open space between crystals. (e) BSE image of lamella in crack-seal textured quartz from The Ov-
ens containing abundant euhedral tourmaline and mica plates. (f, g) Silicate-rich fluid inclusions that characterize the dark quartz columns
from sample in Figure 5a. Note the presence of the V bubble in the inclusions (V with arrows). The white quartz is inundated with inclusions
similar to the inclusion shown in Figure 7a from Caribou.
October 2001 – Gangue No. 71
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Fig. 6. 40Ar/39Ar age spectra for hydrothermal biotite and whole rock
slates from veins in the Tangier gold district. Note that there is distinct
time gap between the whole rocks ages, recording the regional Aca-
dian deformation, and the age of biotite formation, recording the time
of vein formation. For more information see Kontak et al. (2001). DTXHRXV
LVRFKRUHV
with wall rocks, as indicated by alteration, replacement textures in some
veins, and stable isotopic data; and (5) fluid pressures fluctuated from
lithostatic to supralithostatic during vein formation. These constraints are
interpreted to suggest that the deposits reflect incursion of an exotic,
metamorphic fluid into a previously folded stratigraphy undergoing late
stage fold tightening. The nature of individual deposits reflects the varia-
tion of initial fold geometry, host rock stratigraphy (metasandstone:slate
-
ratio), ambient pressures, fluid pressure, and composition of the wall
rocks. 3UHVVXUH NEDUV P
IMPLICATIONS FOR FUTURE WORK
Past work on MGD has resulted in an integrated model that accommo-
dates the important, common features within gold districts. This model
can be used to generally understand the nature of veins to be expected
for a given stratigraphy and fold style. However, historical mining and
more recent detailed structural analysis indicate that variations occur FDUERQLF
among deposits and that each must be treated separately in order to fully LVRFKRUHV
appreciate what controls veining. In addition, the distribution of gold
Q
within deposits is not uniform and is known to occur within ore shoots.
The controls on the nature of these ore shoots, which often define the
economic concentrations of gold within a deposit, remain poorly under-
stood. Thus, identification and detailed mapping of such structures is of
paramount importance if economically successful mining of MGD is to
occur. The presence of disseminated gold mineralization (e.g., Touquoy
Zone) provides a new style of gold deposit in the MT, one with relatively
more uniform grade and possibly larger tonnage potential than veins,
which may provide a new target for future exploration and development.
ACKNOWLEDGMENTS
R
Work on the Meguma gold deposits has been done over a period of many
7HPSHUDWXUH &
years and the authors sincerely appreciate the past and continued support Fig. 7. P-T plots for carbonic and aqueous isochores for fluid inclu-
of Nova Scotia Department of Natural Resources management during sions from Caribou (a) and Tangier (b) gold deposits. Note the large
this time. Many of the deposits mentioned in this paper were visited dur- range in the inferred pressure of entrapment within deposits and also
ing various stages of exploration and development and we acknowledge large difference in pressure between the two deposits. The difference
the support of company personnel who provided access to underground in mole% CO2, in the inclusions for the two areas, as inferred from
workings, drill core, and geological information; without this support our phase proportions and Th(CO2) values (note CO2 homogenizes to V
work would have been severely limited. in Tangier inclusions), is consistent with the pressure difference in-
ferred from isochores.
REFERENCES
Benn, K, Horne, R.J., Kontak, D.J., Pignotta, G., & Evans, N.G., 1997.
Syntectonic emplacement of the South Mountain Batholith, Meguma Christie, A.B., Corner, N.G., Bierlein, F.P., Smith, P.K., Ryan, R.J., &
Terrane, Nova Scotia: magnetic fabric and structural analyses. Bulletin Arne, D.C., 2000. Disseminated gold at Reefton, South Island, New Zea-
Geological Society of America, v. 109, p. 1279-1293. land, compared with similar occurrences in Victoria, Australia and Nova
Scotia, Canada. New Zealand Mining, v. 28,
October 2001 – Gangue No. 71
Henderson, J.B., Henderson, M.N., & Wright, T.O., 1990. Water-sill
hypothesis for the origin of certain veins in the Meguma Group, Nova Malcolm, M., 1929. Gold fields of Nova Scotia. Geological Survey of
Scotia, Canada. Geology, v. 18, p. 654-657. . Canada, Memoir 385.
Horne, R.J. & Culshaw, N., 2001. Flexural-slip folding in the Meguma Newhouse, W.H., 1936. A zonal gold mineralization in Nova Scotia.
Group, Nova Scotia, Canada. Journal of Structural Geology, v. 23, p. Economic Geology, v. 31, p. 805-831.
1631-1652.
Robert, F., Boullier, A.-M., & Firdaous, K., 1995. Gold-quartz veins in
Kontak, D.J., Smith, P.K., Kerrich, R., & Williams, P., 1990. Integrated metamorphic terranes and their bearing on the role of fluids in faulting.
model for Meguma Group lode gold deposits, Nova Scotia, Canada. Ge- Journal Geophysical Research, v. 100, p. 12861-12879.
ology, v. 18, p. 238-242.
Ryan, R.J. & Smith, P.K., 1998. A review of mesothermal gold deposits
Kontak, D.J., Horne, R.J., Sandeman, H., Archibald, D.A., & Lee, J.K. of the Meguma Group, Nova Scotia, Canada. Ore Geology Reviews, v.
W. 1998: 40Ar/39Ar dating of ribbon-textured veins and wall-rock mate- 13, p. 153-184.
rial from Meguma lode gold deposits, Nova Scotia: implications for tim-
ing and duration of vein formation in slate-belt hosted vein gold depos- Sangster, A.L., 1990. Metallogeny of the Meguma Terrane, Nova Scotia.
its. Canadian Journal of Earth Sciences, v. 35, p. 746-761. In: Sangster, A.L., Mineral Deposits of Nova Scotia. v. 1, Geological
Survey of Canada, Paper 90-8, p. 115-162.
Kontak, D.J., Horne, R.J., Smith, P.K., & Archibald, D.A., 2001.
40
Ar/39Ar dating of hydrothermal biotite associated with high-grade gold Editors’ Note: This invited contribution was one of the Boldy award
mineralization in the Whin Vein, Tangier gold deposit (NTS 11D/15), presentations at this years GAC/MAC meeting in St. John’s Nfld.
southern Nova Scotia. Report of Activities for 2000, Nova Scotia De-
partment of Natural Resources, Report 2001-1, Edited by D.R. Mac-
Donald, p. 29-36.
Kretz, R., 1983. Symbols for rock forming minerals. American Miner-
alogist, volume 68, p. 277-279.
The Metal Mining Agency of Japan (MMAJ), a governmental
body involved with metal supplies, wishes to provide informa-
tion on the mineral resources of Asia to potential private inves-
tors - major exploration companies, junior companies and oth-
ers - in order to facilitate new private investment in the region.
The speakers, largely exploration geologists with extensive ex-
perience across Asia, will review the metallogeny, mineral de-
posits and potential for exploration and development across the
region - from Far East Russia to Iran, and Kazakhstan to the
Philippines. The regulatory and investment climate will also be
touched upon. Senior managers from industry will close the Fo-
rum with a discussion of the practicalities of working in Asia.
Registration fee (includes buffet lunch): $90
Late registration (after January 9, 2002): $165
Register early as seating is limited!
To Register for the MMAJ Forum and/or the Cordilleran
Roundup please see recent issues of the Northern Miner, or
download forms from the British Columbia & Yukon Chamber
of Mines web site:
www.chamberofmines.bc.ca/rdup2002
or contact the BCYCM directly tel: 1-604-681-5328, email:
chamber@chamberofmines.bc.ca
For the Final Program and list of speakers, watch for updates at
www.chamberofmines.bc.ca/rdup2002
Or contact Jeff Hedenquist at MMAJforum@aol.com
October 2001 – Gangue No. 71
Conference Report
2001 Gordon Research Conference: Inorganic Geochemistry Related to Mineral Deposits
August 19 to 24, 2001, New Hampshire, USA
The aim of the Gordon Research Conference is to provide an international forum for the presentation and discussion
of frontier research in sciences and its application. The Inorganic Geochemistry section of the Gordon Research Con-
ference is held every four years and provides a great opportunity to share new ideas and results of pioneering research
with colleagues in academia, government, and industry. This year the conference was held at Proctor Academy in
New Hampshire, and had as its theme “the formation, modification, and preservation of ore deposits, with a focus on
geochemical processes related to tectonic, climatic and surficial factors”. It was successfully organized by Jean Cline,
Jeff Hedenquist, and John Thompson.
The Conference had 8 technical sessions, spread over 5 days, including (1) a review of the characteristics of metal
concentrations and their exploration: Industry perspectives, chaired by Eric Seedorff, (2) Chemical and biological
processes involved in metal mobility, led by Gordon Southam, (3) Interrelationships among large-scale climatic/
tectonic processes and metal mobility and concentration, headed by Dick Holland, (4) Processes leading to the near-
October 2001 – Gangue No. 71
surface enrichment of Cu and Au, chaired by Steve Garwin, (5) Processes that may preserve or destroy metal concen-
trations in subaerial and submarine environments, led by Steve Kesler, (6) Processes leading to near-surface concen-
trations of Fe, Ni and Mn, guided by Hiroshi Ohmoto, (7) Processes of fluid flow in the crust that may concentrate
metals, chaired by Grant Garven, (8) Large tectonic processes leading to metal concentration and the formation of ore
deposits, chaired by Dick Tosdal. The conference ended with a panel discussion on research frontiers guided by Ross
Large, Larry Cathles, Murray Hitzman, Jim Franklin, and Noel White. Have a look in the web site (www.grc.uri.edu/
programs/2001/inorgeo.htm) for more information about the program.
In addition, the conference included 42 posters covering all aspects of ore formation and modification and informal
afternoon sessions on porphyry copper deposits, supergene precious metal deposits, and LA-ICP-MS: applications and
problems. There were 105 participants from 14 countries, representing various sectors of the mineral industry, acade-
mia and government. In order to encourage open communication, the conference has a restriction that the information
from the talks, poster and informal sections is not for public use. Consequently, conference proceedings are not avail-
able.
The conference and session coordinators generated a great environment that allowed the interaction among profes-
sionals of the various sectors and mature and young scientists. The sessions were very well organized and the discus-
sions very productive. In addition, Larry Meinert successfully led the 9th meeting of the “Hydrothermal Fluid Society”
with tasting of more than 120 bottles of wine from various countries. It definitely animated the discussions at the
poster sessions.
Please take the opportunity to attend the next Inorganic Geochemistry section of the Gordon Research Conference and
to share and be aware of frontier research on Ore Deposits.
Great job, Jean, Jeff and John!
Gema R. Olivo, Department of Geological Sciences and Geol. Eng, Queen's University, Kingston, Ontario,
Canada, K7L 3N6; olivo@geol.queensu.ca
MDD Awards
It is time again to pull out the pens and nominate your friends and colleagues for the two prestigious Min-
eral Deposits Division awards. It’ll give you a warm feeling for Christmas!
The Duncan R. Derry Medal is the highest award bestowed by the Mineral Deposits Division (MDD)
of the Geological Association of Canada. It is awarded annually to an outstanding economic geologist who
has made contributions to the science of economic geology in Canada. Candidates should be recognized for
their skill and stature as professional economic geologist, and also by their public contributions to the sci-
ence. It is acknowledged that publication is the prime, but not the only method, of disseminating scientific
information in any discipline. Candidates should be members of the GAC, and preferably, but not necessar-
ily, MDD members. The Young Scientist award (William Harvey Gross Medal) is awarded to someone un-
der the age of 40 years old, who has contributed in a substantive way to Mineral Deposits in Canada.
The William Harvey Gross Award is awarded annually by the Mineral Deposits Division of the Geo-
logical Association of Canada to a young geologist (less than 40 years of age on December 31, 2001) who
has made outstanding contributions to the field of economic geology in a Canadian context. The recipient
may be a Canadian or a non-Canadian who has made a contribution in Canada or a contribution with a dis-
tinctively Canadian flavour. The contributions on which the award is based may relate to mineral exploration
or development, scientific research either applied or fundamental, and field-based studies, that is, to include
all aspects of what a generally referred to as economic geology and which represents the broad spectrum of
fields to which Bill Gross contributed. The award consists of a medal and a cash supplement supported
through an endowment fund provided by Corona Corp. Donations by the friends and family of Bill Gross
provide a contribution toward the travel expenses for the recipient and spouse to attend the annual luncheon
of MDD to receive the award. CONTACT Dan Marshall (Medals Committee) email: marshall@sfu.ca
October 2001 – Gangue No. 71
CONSTRAINTS ON THE ORIGIN OF FLUIDS RESPONSIBLE FOR IRISH-Zn-Pb-
BARITE DEPOSITS: EVIDENCE FROM THE CHEMISTRY OF FLUID INCLUSIONS
Iain M. Samson, Department of Earth Sciences, University of Windsor, Windsor, Ontario, Canada N9B 3P4
David A. Banks, Department of Earth Sciences, University of Leeds, Leeds, U.K. LS2 9JT
Adrian J. Boyce, Scottish Universities Environmental Research Centre, East Kilbride, U.K. G75 0QF
INTRODUCTION During the evaporation of seawater, the concentrations of both Cl
and Br increase in a regular manner until halite-precipitation oc-
The numerous, large base-metal deposits hosted by Carbonifer- curs (Fig. 1). During halite precipitation, the concentration of Cl
ous rocks in the Irish Midlands, make this area one of the major remains constant, and, because Br is essentially excluded from
Zn-Pb provinces in the world. Despite significant exploration and the halite structure, Br concentrations increase in the residual
research there is still disagreement on the origin of the mineraliz- brines (Fig. 1). This results in low Cl/Br ratios in residual
ing fluids responsible for these deposits. In order to help resolve evaporitic brines. In contrast, brines generated by the dissolution
this question, we have directly measured the concentrations of of halite have very high Cl/Br ratios because of the low Br con-
Na, K, Li, Cl and Br in fluids related to mineralization by analyz- tent of halite (Fig 2). Because Cl and Br behave conservatively
ing fluid inclusions from the Tynagh and Silvermines deposits during most fluid-rock interactions, the Cl/Br ratio of mineraliz-
using a crush-leach technique. Representative samples of ore- ing brines is therefore useful in testing models involving seawater
stage quartz, sphalerite, barite and carbonate and of post-ore car- or evaporite-derived brines.
bonate were used to constrain the possible sources for the fluids The majority of ore-stage fluids from Silvermines and Tynagh
both during and after mineralization. lie close to the line representing evaporation of seawater (Fig. 1).
There are currently two models that are thought to be viable Dispersion from the line may be explained by analytical uncer-
in explaining the source and flow regime of the ore fluids. The tainty, or small contributions from higher salinity residual brines
model of Russell (1978) proposes that, during a period of exten- (lower Cl/Br) or dissolution of halite (higher Cl/Br). The bulk of
sion and high heat flow, hydrothermal convection cells developed the fluids, however, originated from evaporated seawater that had
in which Carboniferous seawater penetrated the crust to depths of not reached halite saturation. The fluids with low salinity are in-
8-15 km and leached metals from the thick Caledonian geosyncli- terpreted to represent dilution with low salinity (meteoric?) flu-
nal pile. The fluids were then returned to the sites of mineraliza- ids. The majority of Tynagh post-ore carbonates also lie close to
tion via faults. The second model (Hitzman and Beaty, 1996) pro- the seawater evaporation line but have salinities that indicate they
poses topographically-driven flow akin to that proposed for many are derived from seawater that has evaporated past the point of
Mississippi Valley-type deposits. They suggest that formation halite precipitation (Fig. 1).
waters, derived from, and travelling through, the Old Red Sand- The Na-K-Li systematics of the fluids reflect the non-
stone sequences, were driven northwards by a hydrologic head conservative nature of these elements. The ore-stage fluids all
supplied by Hercynian mountains to the south. The fluids may have Na/Br ratios that lie to the left of the evaporation trend indi-
have been heated by relatively deep flow or by a higher than nor- cating depletion in Na. This is partially matched by increased K
mal geothermal gradient at shallower flow depths. Metals are and Li in the fluids relative to evaporated seawater (not shown),
thought to have been sourced from destruction of minerals within and is interpreted as K-Na and Li-Na exchange during water rock
the O.R.S. interaction. Calcium-sodium exchange is also thought to have
occurred. The spread in the data shown by the ore-fluids at Ty-
FLUID INCLUSION CHEMISTRY nagh is likely to represent a mixing between two different sea-
water-related fluids. The Tynagh post-ore carbonates plot almost
Microthermometric data (e.g., Samson and Russell, 1987; Banks on the seawater evaporation line and have been relatively unaf-
and Russell, 1992) indicate that two fluids were involved in the fected by exchange reactions involving Na indicating that they
ore-forming process. The fluid carrying the metals had a salinity have not interacted with the same lithologies as the ore-fluids.
of between 12 and 18 equiv. wt. % NaCl and a temperature of
200 to 280oC. The other fluid, which is believed to be the reser- CONCLUSIONS
voir for reduced sulphur, had a higher salinity of approximately
25 equiv. wt. % NaCl and a temperature of less than 140oC. Overall the evidence from the halogen chemistry of the fluid in-
There is evidence to suggest that mixing of the two fluids oc- clusions points to the existence of fluids related to seawater that
curred, mostly in the subsurface and to a lesser extent when the had evaporated to different degrees. The ore fluids at Silver-
hot, metal-bearing fluid, exhaled into high-salinity brine pools in mines and Tynagh had not precipitated halite whereas the fluid
the Carboniferous Sea. inclusions in post-ore carbonates are residual brines remaining
Chloride and Br are particularly useful in determining the after halite precipitation. The fluid inclusions related to the ore-
sources of hydrothermal fluids, especially if seawater is involved. stage at Tynagh represent mixing of evaporated seawater, proba-
bly similar to the ore fluids at Silvermines, and residual brines
October 2001 – Gangue No. 71
sible for mineralization, is a dominantly fluvi-
atile sequence of red beds. It is not clear what
the source of salinity in their model would be
but, given the depositional environment for these
sediments, presumably requires dissolution of
evaporites. The data presented here are therefore
inconsistent with a model in which O.R.S. for-
mation waters were driven northwards by the
hydraulic head created by Hercynian uplift to the
south.
REFERENCES
Banks, D.A. & Russell, M.J., 1992. Fluid mixing
during ore deposition at the Tynagh lead-zinc
deposit in Ireland. European Journal of Mineral-
ogy, v. 4, p. 921-931.
Everett, C.E., Rye, D.M., Wilkinson, J.J., Boyce,
A.J., Ellam, R.M., Fallick, A.E., & Gleeson, S.
Figure 1. Log Cl vs. Log Br of the fluid inclusions showing that the ore-fluid was A., 1999. The genesis of Irish-type Zn-Pb depos-
originally evaporated seawater. The fluid responsible for post-ore dolomitization its: Characterization and origin of the principal
was also seawater that evaporated to higher salinities and precipitated halite. ore fluid. In, Stanley, C. J. et al. (eds). Mineral
Deposits: Processes to Processing. Proceedings,
5th biennial SGA meeting and 10th quadrennial
IAGOD symposium. 1999. Rotterdam, A.A.
Balkema., p. 845-848.
Gleeson, S. A., Banks, D. A., Everett, C. E., Wil-
kinson, J. J., Samson, I. M., and Boyce, A. J.
1999. Origin of mineralising fluids in Irish-type
deposits: Constraints from halogens. In, Stanley,
C. J. et al. (eds). Mineral Deposits: Processes to
Processing. Proceedings, 5th biennial SGA
meeting and 10th quadrennial IAGOD sympo-
sium. 1999. Rotterdam, A.A. Balkema., p. 857-
860.
Hitzman, M.W. & Beaty, D.W., 1996. The Irish
Zn-Pb-(Ba) orefield. In: Sangster, D.F. (ed.)
Carbonate-hosted Lead-zinc deposits. Society of
Economic Geologists Special Publication 4, p.
112-143.
Figure 2. (a) Cl/Br(m) vs. Na/Br (m) of fluid inclusions. The highest salinity fluids Russell, M.J., 1978. Downward excavating
plot almost on the seawater evaporation line. Ore-fluids plot farther to the left of hydrothermal cells and Irish-type ore deposits:
the seawater line indicating exchange of Na for other cations. importance of an underlying thick Caledonian
prism. Transactions of the Institute of Mining
and Metallurgy, v. 87, p. B168-B171.
with meteoric water or seawater. The same fluids have been
identified in veins in the lower Paleozoic basement (Everett et al., Samson, I.M. & Russell, M.J., 1987. Genesis of the Silvermines
1999; Gleeson et al., 1999), which, taken with the temperatures zinc-lead-barite deposit Ireland: fluid inclusion and stable isotope
and isotopic data, indicate fluid flow from the basement. These evidence. Economic Geology, v. 82, p. 371-394.
data are all consistent with the seawater convection model of
Russell (1978). Editors’ Note: This was one of three presentationsgiven at the
The Old Red Sandstone sequence, hypothesized by Hitzman GAC/MAC in St. John’s who received Boldy awards for Best
and Beaty (1996) to be the source of the formation waters respon- Presentation.
October 2001 – Gangue No. 71
International Symposium on Vanadium
Symposium International sur le Vanadium
AUGUST 11-14, 2002
Vanadium is a strategic metal. 90% is used to toughen and strengthen carbon steels, tool steels,
and high-strength low-alloy steel(particularly for pipelines). Titanium-aluminum-vanadium alloys are being used in the aerospace in-
dustry. Small but growing amounts are used in catalysts and electronics. New uses are continually being discovered for this metal.
An exciting new application is the vanadium redox battery for use as secondary batteries in generating plants and back-up power
sources. It is hoped to include a short course on "Electrochemical Energy Storage Systems and Applications" given by the in-
ventor of vanadium redox batteries, Prof. M. Skyllas-Kazacos of Sydney, Australia.
Topics
The symposium will cover various aspects of the vanadium industry, including the market for vanadium oxides and ferrovanadium
from the leading global producers, new properties currently being developed, and the latest on new discoveries and emerging mar-
kets. To this end, the organisers are soliciting papers for sessions on: Geology, Mineral processing, Recycling Steel alloys, Non-
ferrous alloys (e.g., Ti-Al-V alloys for the aerospace industry) , Chemical applications (e.g., catalysts, vanadium redox batteries),
Marketing and financing a project related to vanadium.
International Organizing Committee:
Émile Beauchamp: Industry Canada, Montréal, Canada
Jacques A. Boivin: COREM, Quebec, Canada
Robert Bryce: McKenzie Bay, Val d'Or, Canada
C.K. Gupta: Bhabha Atomic Research Center, India
Patrick Houle: Ministère des Ressources Naturelles du Québec, Chibougamau, Canada
Maria Skyllas-Kazacos: UNSW, Sydney, Australia
Jacques Laperrière: Développement Économique Canada, Val d'Or, Canada
James McCann: SOQUEM, Quebec, Canada
Dave Peck (tentative): Falconbridge Ltd.,Winnipeg, Canada
Louis Perron: Natural Resources Canada, Ottawa, Canada
John Szabo: Industry Canada, Ottawa, Canada
Mehmet F Taner: Consultant, Ottawa, Canada
André Y. Tremblay: University of Ottawa. Ot-
tawa, Canada
COM 2002, MetSoc & CIM Information:
www.metsoc.org
Abstract Submissions Online:
www.metsoc.org/conferences/com2002/
abstract_form.asp
Submission Deadline: January 31, 2001
Other Information, Please Contact:
Dr. Mehmet F. Taner
Consulting Geologist and Mineralogist
1107 Gablefield Private
Gloucester, Ontario Canada K1J 1E3
Tel: 613-747-2862
E-Mail: mftaner@globalserve.net
Exploration and Mining Geology—CIM’s quarterly journal
Issue number 2 for volume 9 (EMG) is now available; the table of contents and abstracts
for this volume can be viewed at the EMG web site.
http://www.cim.org/geosoc/indexEmg.html
Issue number 2, a special issue featuring Great Canadian Ore Deposits, is nearly ready for
distribution. Subscriptions to volume 9 are available to members of MDD at a special af-
filiated rate of $CDN 75/ $US 55.
October 2001 – Gangue No. 71
The Mineral Deposits Division of the Geological Association of Canada and the Geological Survey of Canada
are pleased to announce the release of the highly anticipated MDD Special Volume #1
on the world class Sullivan Zn-Pb Mine, British Columbia, Canada.
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October 2001 – Gangue No. 71
Geological Gathering marks Sullivan Mine close
Mine closings are sad, and when one of Canada’s true greats closes its portal, it’s doubly so. But what a
time we had at the closing ceremonies for the Sullivan Mine. On November 9 and 10 about 200 geolo-
gists from across North America came to see friends, to remember earlier times at Sullivan and to hear
the latest ideas on the geology of the mine where four generations of geologists have worked. Former
employees and former and first-time visitors came to the mine that has been a must-see for every Cana-
dian geologist for a century.
The events included a series of eleven retrospective and forward-looking talks about the geology of
the mine and it’s setting. One talk presented tantalizing geophysical evidence for the existence of the
faulted northern extension of the Sullivan ore body at about 2km depth.
A superb show-and-tell that included a range of wonderful posters and historical photos ran the day
after the talks. The quality and volume of the data on display were impressive; they represent about 100
years of geological work by innumerable scientists. Many attendees expressed the hope that this geologi-
cal legacy be preserved and archived as a research collection.
For me the highlight was the opportunity to go underground one last time to see, worship, and collect
some of the fabulous bedded mineralization. We saw the elaborate mine model, an artifact of decades of
work, which despite having been overtaken by the digital age, still gives the best overview of the deposit.
The company staff organized 9 separate tours; 180 people went underground. This was the largest con-
tingent to have toured the mine in one day since it opened. In the evening the company hosted a superb
social evening with a banquet of great food, drink ,and many toasts. This was an opportunity to see old
friends and to reminisce.
MDD chose the event to launch its Special Publication #1, the “last word on the Sullivan”. This opus
magnum represents the work of many scientists during the last decade and is an 834-page compendium
of some 42 papers on a range of subjects related to the Sullivan deposit that includes a data CD. John Ly-
don of the GSC edited the book. He has put much of the last decade [of his life] into making the book
something to match the uniqueness of the deposit it details. The entire shipment of 80 volumes sold out
in two hours.
Teck Cominco deserves much
credit and thanks for a most
memorable Sullivan send-off.
Two GAC past presidents, John
Hamilton and Hugh Morris,with
the help of Rob Edmunds were
the prime organizers of the
events.
It used to be we went to mine
openings; now closings are the
sign of the times. If you have to
have them, this is the way to do
it.
Dirk Templeman-Kluit
October 2001 – Gangue No. 71
October 2001 – Gangue No. 71
MEETINGS, WORKSHOPS, & FIELDTRIPS
2001
• December 10-17—Sediment-Hosted Lead-Zinc Sulfide Deposits in the Northwestern Indian
Shield, Dehli, India (see advert)
2002
• January 22-25 — Cordilleran Roundup: www.chamberofmines.bc.ca.
• February 25-27 — SME Annual Meeting and Exhibit, Phoenix, Arizona. For Information, email: sme@smenet.org
• March 10-13 — Prospectors & Developers Association of Canada (PDAC) International Convention & Trade Show,
Toronto, Canada. For Information, email: info@pdac.ca
• April 14-16 — SEG Global Exploration 2002: Integrated Methods for Discovery, Denver, Colorado. www.seg2002.org
• May 27-29 - GAC/MAC Joint Annual Meeting, Saskatoon, SK. Www.usask.ca/geology
• July 22-24— PACROFI 2002, 8th biennial Pan-American Conference on Fluid Inclusions, Halifax, NS. Www.gov.ns.
ca/natr/meb/pacrofi8/zindex.htm.
• July 22-26 - IAGOD Symposium and Geocongress 2002: Sedimentary, Magmatic and Ore-forming responses to
Compressional and Extensional Tectonics: A focus on Africa. Safari Hotel, Windhoek, Namibia.
www.geoconference2002.
• August 11-14 - Ti-V conference, CIM MetSoc, Montreal, QC. Www.metsoc.org
• August 18-23 - Goldschmidt Conference2002, Davos Switzerland. Www.goldschmidt-conference.com
• September 18 - 20 - Metallogeny of Precambrian Shields, Kyiv, Ukraine. Contact: Dr.V.Guliy, Ukrainian State Geo. Re-
search Institute, 78 Avtozavods'ka str., Kyiv, 04114, Ukraine; Tel./Fax: (380) 44-295-7298; email: guliy@vng.usr.pu.ru
• September 22-25 - Applied Structural Geology for Mineral Exploration and Mining, 2002. Kalgoorlie, Western Aus-
tralia. For information, Julian Vearncombe, email: vearncom@iinet.net.au.
• October 27-30 - Geological Society of America Annual meeting. Denver Colorado. Www.geosociety.org
The Geological Association of Canada-Mineralogical
Association of Canada Joint Annual Meeting for 2002 is being
hosted by the University of Saskatchewan in Saskatoon. The
meeting will have technical sessions and field trips of interest to
the whole of the Earth Science community. However, listed
below are those that are being sponsored by the Mineral Deposits
Division and which will be of particular interest to both academic
and industry geoscientists:
Symposia: “Applications of Synchrotron Light Sources to the Earth Sciences”
Special Sessions: “New Insights into Archean Gold Deposits: Yellowknife EXTECH III”, “The Albian-Cenomanian Central
Saskatchewan Kimberlite Field and Relationships to Western Canadian Sedimentary Basin Host Strata”, and “The Athabasca
Basin and It’s Uranium Deposits.”
A “hands-on” Short Course organized by Steve Scott (University of Toronto) on “Modern and Ancient VMS Deposits: Their
Geology and Exploration.”
Field trips: “The Eastern Athabasca Basin and It’s Uranium Deposits”, “Tectonic and Sea-floor Hydrothermal Evolution of the
Paleoproterozoic Snow Lake Assemblage, Flin Flon Belt”, ”Shear-Hosted Gold Occurrences in the Proterozoic La Ronge
Volcanic Belt,Northern Saskatchewan”, and “EXTECH III – The Gold is Out There (Yellowknife Gold Belt).”
This is an open invitation to everybody to attend the conference, and submit abstracts for oral or poster presentations to these
th
sessions or the general session on Economic Geology. The deadline for abstracts is January 15 , 2002. Guidelines for abstract
preparation, conference details, and contact people for the sessions listed above are available at
http://www.usask.ca/geology/sask2002/. For further information on MDD activities at the conference, or field trips, please contact
Kevin Ansdell (kevin.ansdell@usask.ca).
October 2001 – Gangue No. 71