Yellowknife

The NICO deposit is located at the south end of the GBMZ in the Proterozoic Bear Structural Province of the Canadian Shield, about 160 km northwest of Yellowknife, Northwest Territories (Fig. 1). It represents an economically significant source of Co-Au-Bi-Cu-Fe with calculated reserves of 21.8 Mt with 1.08g/t Au, 0.13%Co and 0.16% Bi (Fortune Minerals 2008). Mineralization at NICO consists of a number of mineral showings predominantly hosted in brecciated and altered siltstone and wacke of the 1.88 Ga... 

Diavik Diamond Mine Inc. is located on an island in Lac de Gras, 300 km northeast of Yellowknife, NT (Fig. 1).). Open pit mining will lead to the eventual development of two 200 Mt permanent stockpiles of waste rock. The country rock consists of granite averaging <0.04 wt.% S and biotite schist averaging >0.08 wt.% S. Both rock types contain low concentrations of carbonate minerals. 

Figure 19. Plot of Li isotopic composition vs. inverse Li concentration for lakes and basinal/oilfield brines. Lakes open circle = major global lakes (Chan and Edmond 1988 Falkner et al. 1997) semi-open circle = western U.S. closed basin lakes (Tomascak et al. 2003). Oilfield brines inverted triangle = Williston basin, Saskatchewan (Bottomley et al. 2003) diamond = Israeli oilfields (Chan et al. 2002d). Mine waters (Canadian Shield basinal brines) square = Yellowknife, NWT (Bottomley et al. 1999) triangle = Sudbury, Ontario, area (Bottomley et al. 2003) star = Thompson, Manitoba, area (Bottomley et al. 2003). Average composition of seawater is included for reference.

In terms of Li content and isotopic signature, the Yellowknife mine waters are similar to waters from Sudbury (Ontario) area mines (0.05 to 2.9 ppm Li and 5T i = +27.9 to +42.6 Bottomley et al. 2003). Composihons of the Sudbury brines are consistent with predominance of preserved marine Li. These waters contrast with samples from mines in central Manitoba, which are dilute (Li concentration < seawater) and show a wide range of 5 Li (+15.0 to +46.9 Bottomley et al. 2003). These waters are plausibly mixtures of isotopically heavy brine (developed through fluid-rock interachon in fracture zones) and waters that had interacted with isotopically hght cormtry rocks. 

The Hackett River VMS deposits are hosted within the Ignerit Formation and are part Yellowknife Supergroup within the Slave Craton. The Ignerit Formation consists of highly silicified felsic volcanic rocks of calc-alkaline affinity that are intercalated with discontinuous lenses of calc-silicate that are interpreted to be tuffs... 

University of New Brunswick, 2 Bailey Drive, Box 4400, Fredericton, NB, E3B 5A3 CANADA Northwest Territories Geoscience Office, 4601-B 52nd Ave, P.O. Box 1500, Yellowknife, NT, X1A 2R3 CANADA... 

Shelton, K.L., McMenamy, T.A., van Hees, E.H., Falck, H. 2004. Deciphering the Complex Fluid History of a Greenstone-Hosted Gold Deposit Fluid Inclusion and Stable Isotope Studies of the Giant Mine, Yellowknife, Northwest Territories, Canada. Economic Geology, 99, 1643-1663. 

Case-3 Rare Earth Mineral (REE) Deposits. The Thor Lake rare metals deposits are hosted by the peralkaline Blachford Lake intrusion, an Aphebian ring complex emplaced in Archean-supracmstal rocks of the Yellowknife... 

Wise, M. A. Cerny, P. 1990. Primary compositional range and alteration trends of microlite from the Yellowknife pegmatite field, Northwest Territories, Canada. Mineralogy and Petrology, 43, 83-98. 

Canada near Yellowknife, Northwest Territories Grace, Meg, Keg, Kam, and Peg lakes Mining 11 —530 ( 1.5 pm filtered) Bright, Dodd and Reimer (1996)... 

Northwest Territories Yellowknife region Ore deposits and mining wastes Mudroch et al. (1989) Halbert et al. (2003 Walker et al. (2005) Ollson et al. (2003... 

Mudroch, A., Joshi, S.R., Sutherland, D. et al. (1989) Geochemistry of sediments in the Back Bay and Yellowknife Bay of Great Slave Lake. Environmental Geology and Water Sciences, 14(1), 35-42. 

Ollson, C.A., Reimer, K.J., Koch, I. and Cullen, W.R. (2003) Contaminant bioavailability and its consequences for ecological and human health risk assessment case study arsenic in Yellowknife, NWT, in Proceedings — Assessment and Remediation of Contaminated Sites in Arctic and Cold Climates (eds M. Nahir, K. Biggar and G Cotta) University of Alberta, Edmonton, AB, Vol. 3, pp. 129-38. 

Folinsbee, R. E. Archean monazite in beach concentrates, Yellowknife geologic province, Northwest Territories, Canada. Trans. Roy. Soc. Can. Ser. 3, IV, 49, 7 (1955). 

A truck leaves Yellowknife in early January when the temperature is -30.0°C. The tires of the truck are inflated to 210 kPa. Four days later, the truck arrives in California where the temperature is 30.0°C. What is the air pressure in the tires when the truck arrives at its destination ... 

Because of the continuous presence of seismic background noise, only explosions whose yield exceeds a certain value are detected. This detectability limit varies with the distance from the explosion point and increases with the amplitude of the background noise. In the case of the Pacific Test Centre, the station at Rarotonga (Cook Islands), located at approximately 2000 km on a direct uninterrupted line from Mururoa, receives the T waves emitted by weak explosions and thus has a detectability close to one kiloton. The other stations are much further away and, apart from a few particularly sensitive stations such as the Yellowknife network in Canada, they have a much higher detectability limit. 

Bethune, K. M., Villeneuve, M. E. Bleeker, W. 1999. Laser Ar/ Ar thermochronology of Archean rocks in Yellowknife Domain, southwestern Slave Province insights into the cooling history of an Archean granite-greenstone terrane. Canadian Journal of Earth Sciences, 36, 1189-1206. 

CouSENS, B. L. 2000. Geochemistry of the Archean Kam Group, Yellowknife greenstone belt. Slave Province, Canada. Journal of Geology, 108,181-197. 

Helmstaedt, H. Padgham, W. A. 1986. A new look at the stratigraphy of the Yellowknife Supergroup at Yellowknife, N.W.T. implications for the age of gold-bearing shear zones and Archean basin evolution. Canadian Journal of Earth Sciences, 23, 454—475. 

Helmstaedt, H., Padgham, W. A. Brophy, J. A. 1986. Multiple dikes in lower Kam Group, Yellowknife greenstone belt evidence for Archean seafloor spreading Geology, 14, 562-566. 

Henderson, J. B. 1985. Geology of the Yellowknife-Hearne Lake area. District of Mackenzie a segment across an Archean basin. Geological Survey of Canada, Memoir, 414, 135. 

ISACHSEN, C. E. Bowring, S. A. 1997. The Bell Lake Group and Anton Complex a basement-cover sequence beneath the Archean Yellowknife greenstone belt revealed and implicated in greenstone belt formation. Canadian Journal of Earth Sciences, 34, 169-189. 

Archean turbidites from the Yellowknife area, Northwest Territories, Canada. Geochimicaet Cos-mochimica Acta, 63, 2579-2598. 

R. Pienitz. J.P. Smol (1993). Diatom assemblages and their relationship to environmental variables in lakes from the boreal forest-tundra ecotone near Yellowknife, Northwest Territories, Canada. Hydrobiologia, 269/270, 391-404. 

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