The Griz East occurrence is located at an elevation of approximately 1550 metres on the south side of a northeast-flowing tributary of the Toodoggone River, approximately 3.2 kilometres southwest of the river’s junction with Bronlund Creek.
Regionally, the area is situated within a Mesozoic volcanic arc assemblage, which lies along the eastern margin of the Intermontane Belt, a northwest-trending belt of Paleozoic to Paleogene sediments, volcanics and intrusions bounded to the east by the Omineca Belt and to the west and southwest by the Sustut and Bowser basins.
Permian Asitka Group crystalline limestones are the oldest rocks exposed in the region. They are commonly in thrust contact with Upper Triassic Stuhini Group andesite flows and pyroclastic rocks, and marine sedimentary and volcanic rocks of the Lower to Middle Jurassic Hazelton Group. These rocks have been intruded by plutons and other bodies of the mainly granodiorite to quartz monzonite Early Jurassic Black Lake Suite and are in turn unconformably overlain by or faulted against Lower Jurassic calc-alkaline volcanics of the Toodoggone Formation (Hazelton Group).
The dominant structures in the area are steeply dipping faults that define a prominent regional northwest structural fabric trending 140 to 170 degrees. In turn, high-angle, northeast-striking faults (approximately 060 degrees) appear to truncate and displace northwest-striking faults. Collectively these faults form a boundary for variably rotated and tilted blocks underlain by monoclinal strata.
Locally, andesitic lava flows near their contact with a quartz monzonite host quartz-carbonate veins with pyrite, chalcopyrite and galena. It is believed that this volcanic unit is shallowly underlain by Jurassic quartz monzonite related to the Jurassic Black Lake Suite.
Approximately 350 metres to the west, on a steep north-northeast–facing slope, a 1.0- to 2.0-metre wide, silicified, quartz-carbonate-pyrite–flooded shear zone has been traced for at least 25 metres along strike.
In 1999, a sample (JC99-DB-5) from the western shear zone yielded 0.40 gram per tonne gold and 4.0 grams per tonne silver (Assessment Report 26252).
In 2003, two grab samples (132523 and 132655) assayed 2.75 and 0.57 grams per tonne gold, 3.0 and 10.1 grams per tonne silver, 1.00 and 0.700 per cent lead, whereas another sample (133441[?]), taken up slope to the south at an elevation of approximately 1650 metres, assayed 41.7 grams per tonne silver and 0.129 per cent lead (Assessment Report 27429). Another sample (133602[?]), taken to the southwest at an elevation of 1800 metres, yielded 1.00 per cent lead and 1.020 per cent zinc (Assessment Report 27429).
Work History
In 1999, Stealth Minerals staked the initial claims in the area of what is now known as the Sickle-Sofia property and, later that year, Standard Metals conducted a small-scale geochemical program on the area on behalf of Stealth Minerals.
In 2003, Stealth minerals completed a program of rock, silt and soil sampling and 78.4 line-kilometres of ground geophysical surveys on the Pine property. Also, at this time, as part of a private-public partnership with the Geological Survey of Canada and the British Columbia Department of Mines and Energy, the Sickle-Sofia property was included in a multi-parameter helicopter-borne geophysical survey over the Toodoggone district. Several high potassium anomalies and low thorium-potassium ratio anomalies were detected.
In 2004, Stealth Minerals expanded the property package by staking additional claims. A grid-based soil survey was conducted over 27 square kilometres. A total of 728 rock and 2103 soil samples were collected.
In 2005, a program of geological mapping and a 21 line-kilometre induced polarization and ground magnetic geophysical survey was completed over the lower, glacial-fluvial–covered portion of the Sofia (MINFILE 094E 238) copper-gold porphyry target. This survey outlined an 800-metre wide by 1200-metre long +40 millisecond induced polarization chargeability anomaly that was open to the north.
In 2006, Stealth Minerals further expanded the IP/ground magnetic survey by another 21 line-kilometres and expanded the chargeability anomaly a further 600 metres north and 300 metres west. During the 2006 season, a total of 28 rock samples were taken from outcrop and float. Geophysical surveys were completed in the area between and covering the Sofia (MINFILE 094E 238) to Quartz Lake (MINFILE 094E 301) occurrences.
In 2015, a program of geophysical review completed for Cazador Resources Ltd. on the Sofia property identified five target areas.
In 2017, Cazador Resources completed 239.0 line-kilometres of airborne magnetic surveying and a 2.5 line-kilometre ground induced polarization survey on the Sofia property.
See Sickle Creek (MINFILE 094E 237) occurrence for further details of the Stealth Minerals Limited Sickle-Sophia property.
