The Arg showing is located 9.4 kilometres due south of Toodoggone Lake, north of Jock Creek, and 6.75 kilometres north-northeast of the Shasta occurrence (094E 050). The showing is located in the central part of the Toodoggone gold camp, approximately 290 kilometres north of Smithers.
The Arg showing 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 Tertiary 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 Takla Group andesite flows and pyroclastic rocks. Takla volcanics have been intruded by the granodiorite to quartz monzonite Black Lake Suite of Early Jurassic age and are in turn unconformably overlain by or faulted against Lower Jurassic calcalkaline volcanics of the Toodoggone Formation, Hazelton Group.
The dominant structures in the area are steeply dipping faults which 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.
Geological mapping in the Arg showing area shows the area to be underlain by both undivided Jurassic Hazelton Group and the Toodoggone Formation of the Hazelton Group. Feldspar porphyritic flows, crystal lapilli tuffs, pyroclastic breccia, lahar and volcanically derived conglomerate, mudstone and greywacke comprise lithologies of the Hazelton Group, and are believed to be slightly older than those of the Toodoggone Formation. They are generally found in fault contact with the Metsantan Member of the Toodoggone Formation and crop out east of the fault. The Metsantan Member, described regionally as consisting of trachyandesite flows with lenses of lapilli tuff, lahar; minor volcanic sandstone and conglomerate, occurs west of the fault (Bulletin 86). Within the Arg showing area a syenite to quartz monzonite and granodiorite to quartz diorite stock, of the Early Jurassic Black Lake Suite, occurs along the fault contact separating the two volcanic sequences. This northwest trending, lens-shaped stock is informally recognized as the McClair stock (Assessment Report 15264). Late mafic dikes cut the entire sequence.
The Arg showing area is dominated by a northwesterly trending set of structures represented by younger steeply dipping faults and synvolcanic half-graben margins exhibited in Hazelton Group volcanics. Younger post-volcanic and intrusive faults also transect the area with a northwesterly trend. Most of the prominent gossans in the area are also aligned along this trend.
There are numerous gossans in the Arg showing area. They are marked by an extensive zone of disseminated pyrite and intense propylitic alteration (chlorite and epidote). Argillic alteration, consisting of clays, occur along faults. Locally, silicification consisting of blue-white silica with disseminated pyrite is found. Minor amounts of galena and malachite staining have also been found.
Mineralization consists of native copper, bornite, chalcocite and pyrite with anomalous gold-silver in a quartz breccia zone within argillically altered andesitic tuffs (T. Schroeter, personal communication). Mineralization is associated with strong silicification zones and extensive veining with vuggy quartz (Assessment Report 8574). Minor chalcopyrite is also observed in fractures in quartz monzonite (Assessment Report 8574). Barite is also reported near the Arg showing.
Several samples taken in 1980 yielded anomalous results. Sample SC-40-80-15 analysed 0.33 gram per tonne gold, 4.3 grams per tonne silver, 0.55 per cent lead, 0.038 per cent copper and 0.022 per cent zinc (Assessment Report 8574).
In 1986, assay values from samples R262 and R261 yielded 1.6 and 1.0 grams per tonne silver, whereas a nearby sample (R1001) of quartz assayed 0.102 gram per tonne gold and 1.4 grams per tonne silver (Assessment Report 15264).
In 2000, grab samples (PILN-RB00-05), taken approximately 500 metres to the west, of weakly silicified syenite with trace pyrite assayed 0.176 gram per tonne gold over 2.0 metres (Assessment Report 26383).
In 2002, select grab samples (RM02PN-25) over 15.0 metres of epidote-altered syenite with chalcocite(?) in fractures and trace malachite assayed 0.279 per cent copper (Assessment Report 27055).
In 2003, a chip sample (RMR-PN-03-027) of monzonite hosting malachite and chalcocite along fractures, taken from the same area as the 2000 sample, yielded 0.399 per cent copper and 0.275 per cent zinc over 5 metres (Assessment Report 27310).
Work History
In 1969, Cominco Ltd. completed a program of geological mapping and geochemical (rock, silt and soil) sampling on the area as the Theban claims.
In 1971 and 1972, Kennco Explorations Ltd. completed programs of geological mapping and geochemical (rock, silt and soil) sampling program on the area as the Black claims.
In 1980 and 1981, Serem Ltd. completed programs of prospecting, geological mapping and geochemical (rock, silt and soil) sampling on the area as the OJ, Orange, Arg and Argus claims.
During 1985 through 1987, Rhyolite Resources Inc. completed programs of geological mapping, trenching, geochemical (heavy mineral, rock and soil) sampling and a 200 line-kilometre airborne geophysical survey on the Adrian, Argus, Ian, Otto and Paul claims. Also in 1987, Beachview Resources Ltd. prospected and sampled (rock and soil) the area immediately south as the Brooke and Lee claims. In 1988, Rhyolite Resources completed a further program of rock and soil sampling, geological mapping and a 7.2 line-kilometre induced polarization survey on the Ian, Otto, Adrian, Paul and Argus claims. In 1990, Rhyolite conducted a soil geochemical sampling program to extend the coverage of an existing survey grid and to explore a new area within the claim group.
In 1992, Electrum Resources completed a program of heavy mineral sampling on the area as the Pil 1-3 claims. The following year, the Pil claims were expanded and a further program of prospecting and geochemical (heavy mineral, rock and silt) sampling was completed. In 1995, Electrum Resources completed a program of rock and soil sampling and a 9.7 line-kilometre ground magnetic survey on the Pil claims. In 1996, a minor prospecting and sampling program was completed along with LANDSAT TM and Radar imagery review. In 1997, a further program of rock and soil sampling and 28.7 line-kilometres of ground geophysical surveys were completed on the Pil claims. In 1998, Electrum Resource completed a program of geological mapping, geochemical (rock, silt and soil) sampling and a 4.9 line-kilometre ground magnetic survey on the Pil claims.
In 1999, Finlay Minerals purchased the Pil property and conducted a major exploration effort including induced polarization and magnetic surveys, geochemical (soil and rock) sampling and detailed geological mapping. During 2001 through 2007, Finlay Minerals completed further programs of geological mapping, geochemical sampling, trenching, diamond drilling and geophysical surveys on the Pil property. A complete summary of this work can be found in the Pil South (MINFILE 094E 310) occurrence.
In 2015, Finlay Minerals completed a program of geological mapping and geochemical (rock and soil) sampling on the Pil claims.
