Alteration and ore mineral characteristics of the Archean Coniagas massive sulfide deposit, Abitibi belt, Quebec

1998 ◽  
Vol 35 (6) ◽  
pp. 620-636 ◽  
Author(s):  
Pierre Doucet ◽  
Wulf Mueller ◽  
Francis Chartrand
Keyword(s):  
Hanging Wall ◽  
Massive Sulfide ◽  
Sulfide Mineral ◽  
Sulfide Deposit ◽  
Spreading Ridge ◽  
Massive Sulfide Deposit ◽  
Mineral Characteristics ◽  
Fe Content ◽  
Mineralized Zone ◽  
Back Arc

The Coniagas Mine in the northeastern Abitibi greenstone belt is a small, isolated Archean, volcanic-hosted, massive sulfide deposit rich in Zn-Pb-Ag. The Main lens, which is part of four massive sulfide lenses, is restricted to a 40 m thick massive felsic lapilli tuff unit of the 280 m thick sequence. The massive sulfides, a product of subsurface replacement, have features common to both Mattabi- and Noranda-type deposits. The Coniagas Mine sequence represents part of a small subaqueous volcanic edifice that probably evolved close to an arc or back-arc spreading ridge. A distinct alteration halo of chlorite + sericite ± epidote ± spessartine garnet in the immediate footwall and a hanging wall alteration assemblage of quartz + sericite ± epidote ± chlorite characterize the deposit. The sphalerite + pyrite + galena ± chalcopyrite sulfide mineral assemblage in the Main lens differs significantly from the pyrite + chalcopyrite + sphalerite + pyrrhotite ± galena assemblage in the stringer zone. Chlorite compositions are Fe rich close to the mineralized zone, with an Fe/(Fe + Mg) ratio of 0.38-0.48 in the hanging wall and 0.65-0.70 below the ore. Delicate sulfide textures including colloform pyrite and concentric sphalerite are consistent with a low temperature of formation, whereas higher temperatures are inferred for the stockwork zone. Electron probe microanalysis of sphalerite supports inferred hydrothermal fluid temperatures. The low Fe contents (6.7-10.8 mol% FeS) in sphalerite associated with colloform pyrite of the Main lens contrast with the elevated Fe content (12.7-14.1 mol% FeS) in sphalerite from the stockwork.

The Geology and Mineralization of the High Lake Volcanic-hosted Massive Sulfide Deposit, Nunavut

2004 ◽  
Vol 13 (1-4) ◽  
pp. 37-47 ◽  
Author(s):  
C.A. PETCH
Keyword(s):  
Rock Type ◽  
Massive Sulfide ◽  
Sulfide Deposit ◽  
Massive Sulfide Deposit ◽  
Main Zone ◽  
The West ◽  
Primary Metal ◽  
Metasedimentary Rocks ◽  
Slave Province ◽  
Mineralized Zone

Abstract The High Lake polymetallic deposit is located in the northern Slave province, 40 km south of Coronation Gulf, Nunavut. The main zone, the AB zone, hosts an estimated resource of 3.56 Mt grading 5.0% copper, 1.1% zinc, 0.06% lead, 1.7 g/t gold, and 18.2 g/t silver. Archean felsic metavolcanic and metavolcaniclastic rocks are the dominant rock type and are associated with lesser mafic metavolcanic and carbonate-rich metasedimentary rocks. The sequence strikes north-northeast, dips steeply to the west, and is truncated to the west by a large granodioritic intrusion. The mineralization at the AB zone is comprised of massive and stringer chalcopyrite-sphalerite-pyrrhotite-pyrite±galena. At the core of the mineralized zone, intensely chlorite-altered rocks are locally metamorphosed to form distinctive zones of anthophyllite-magnetite-cordierite-altered rock. Peripheral to the mineralized core, alteration consists of sericitization, silicification, and weaker chloritization. Primary morphology and facing direction of the zone are difficult to interpret in part due to poor primary metal zonation of the deposit. However, the irregular shape of the mineralized zone and the erratic zones of zinc enrichment at the fringes are consistent with the interpretation that the zone was formed by the replacement of a porous volcaniclastic pile.

Geology of the Izok Massive Sulfide Deposit, Nunavut Territory, Canada

2004 ◽  
Vol 13 (1-4) ◽  
pp. 25-36 ◽  
Author(s):  
IAN R. MORRISON
Keyword(s):  
Hanging Wall ◽  
Sedimentary Rocks ◽  
Massive Sulfide ◽  
Economic Feasibility ◽  
Open Pit ◽  
Open Pit Mining ◽  
Sulfide Deposit ◽  
Massive Sulfide Deposit ◽  
West Central ◽  
Nunavut Territory

Abstract The Izok Zn-Cu-Pb-Ag volcanogenic massive sulfide deposit is located 265 km south of Kugluktuk (Coppermine), Nunavut Territory, Canada, in the west-central Slave structural province. The Izok deposit is owned 100% by Inmet Mining Corporation and represents one of the largest undeveloped zinc-copper resources in North America. The Izok deposit is hosted within and near the top of a thick sequence of predominantly felsic pyroclastic rocks of late Archean age. The hanging-wall stratigraphy includes additional felsic volcaniclastic rocks, andesitic and basaltic flows, thin sulfide-rich iron formations, and turbiditic sedimentary rocks. The felsic volcanic rocks are intruded by intermediate dikes and sills, followed by gabbroic dikes and sills. Both intrusive suites are interpreted to be volcanic feeders to the overlying flows. All lithologies are subsequently cut by younger, irregular, granitic pegmatite and diabase dikes. The volcanic and sedimentary rocks are regionally metamorphosed to pyroxene hornfels grade. The massive sulfides occur within a large (kilometer-scale) Na-depleted sericitic alteration zone. The immediate footwall and hanging-wall rocks to the deposit are characterized by zones of muscovite-biotite-sillimanite, lesser chlorite-biotite-cordierite, and locally intense silicification and sodium metasomatism. All lithologies have been affected by younger Ca-metasomatism. As currently defined, the Izok deposit comprises a cluster of five complexly zoned composite lenses: the Northwest, North, Central West, Central East, and Inukshuk lenses. The first four lenses are amenable to open-pit mining, whereas the Inukshuk lens will require underground development. The total indicated mineral resource presently stands at 16.5 million tonnes with a grade of 2.2% Cu, 11.4% Zn, 1.1% Pb, and 60 g/t Ag. Inmet Mining Corporation is presently reviewing the economic feasibility of developing the property.

Interpretation of borehole gravity data of the Lalor volcanogenic massive sulfide deposit, Snow Lake, Manitoba, Canada

2015 ◽  
Vol 3 (3) ◽  
pp. T145-T154 ◽  
Author(s):  
Ernst Schetselaar ◽  
Pejman Shamsipour
Keyword(s):  
Gravity Data ◽  
Hanging Wall ◽  
Bouguer Anomaly ◽  
Massive Sulfide ◽  
Geological Mapping ◽  
Sulfide Deposit ◽  
Massive Sulfide Deposit ◽  
Volcanogenic Massive Sulfide ◽  
Volcanogenic Massive Sulfide Deposit ◽  
Gamma Density

We have acquired borehole gravity data along five drillholes intersecting the Lalor volcanogenic massive sulfide deposit hosted in the eastern Flin Flon greenstone belt at Snow Lake, Manitoba, Canada. Inverted apparent interval density (IAID) logs were calculated from the borehole gravity data and compared with lithofacies and [Formula: see text] logs; the latter of which is a geochemical proxy for differentiating volcanic rocks of felsic to mafic composition. The IAID anomalies predominantly reflect alternating mafic and felsic volcanic rock units in the footwall and hanging wall of the massive sulfide deposit. IAID lows are associated with [Formula: see text] highs that correspond to rhyolite and rhyodacite intervals in the hanging wall. IAID lows with associated [Formula: see text] peaks in the footwall occur within intervals of gneiss and schist formed by metamorphism of hydrothermally altered rocks, suggesting that these IAID lows still reflect the felsic composition of their volcanic protoliths. A significant peak-to-peak Bouguer anomaly of 0.66 mGal caused by an estimated excess mass of 0.7 mT can be correlated with gamma-gamma density signature of the main sulfide ore zone in three boreholes. This anomaly is aligned with the ore zone after restoring the displacement along a northeast-dipping structure. When integrated with drillhole lithology and lithogeochemistry logs, gravity borehole data can, in addition to the direct detection of mineralization, be used as a subsurface geological mapping tool.

Oxygen isotope geochemistry of the Sullivan massive sulfide deposit, Kimberley, British Columbia

1984 ◽  
Vol 79 (5) ◽  
pp. 933-946 ◽  
Author(s):  
Bruce E. Nesbitt ◽  
Fred J. Longstaffe ◽  
David R. Shaw ◽  
Karlis Muehlenbachs
Keyword(s):  
British Columbia ◽  
Oxygen Isotope ◽  
Isotope Geochemistry ◽  
Massive Sulfide ◽  
Sulfide Deposit ◽  
Massive Sulfide Deposit
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