Placer gold up to small flake size has been found further up Cottonwood Creek, fine gold can be found lower. The Sherk Lake tenures covers five minfiles and many showings.
The property covers multiple minfiles, showings, as well as a placer gold deposit. The claim area covers the Sherk Lake Area and the entire stretch of Cottonwood Creek. The property covers the Comego deposits. The claims cover a well known deposit originally staked in 1902 and explored for gold.
THE COMEGO MINFILE (092C 018)
The Comego showing is located on the Widow claims about 6.5 kilometres north of Youbou at the headwaters of Chemainus River.
Skarns are developed in the Mississippian to Pennslvanian Fourth Lake Formation (Buttle Lake Group) sediments which have been intruded by Triassic diabase and gabbro sills informally called the Mount Hall gabbro. Mineralization may, however, be related to the nearby Jurassic Reynard Creek diorite stock. The rock types in the area comprise chert, cherty tuffs and sediments, agglomerates and argillites.
Mineralization consists of chalcopyrite, pyrite, pyrrhotite, magnetite, minor molybdenite, sphalerite, tetrahedrite, rare bornite and arsenopyrite. Pyritiferous quartz- carbonate altered shear zones outcrop in the Chemainus River south of the areas of skarn mineralization. Assays from the quartz-carbonate zones are very low. Mineralization occurs as three types: 1) Quartz-calcite-garnet- actinolite skarn with magnetite, chalcopyrite, pyrrhotite, pyrite and locally tetrahedrite replacing sediments 2) Quartz veins hosting molybdenite, pyrite and chalcopyrite; and 3) quartz-carbonate veins in shear zones.
The claims were originally staked in 1902 as the Cascade claim. Considerable exploration has been done on the property including five short tunnels and numerous trenches. In 1963, the Comego claims were explored by a program of geochemical sampling, geological mapping trenching and two diamond drill holes. Grab samples assayed up to 8.9 grams per tonne gold, 27.4 grams per tonne silver, 1.3 per cent molybdenum and 8.3 per cent copper (Assessment Report 641).
In 1969 and 1970, Hibernia Minerals claimed the area as the Anne claim and completed programs of soil geochemical sampling, geological mapping and a ground electromagnetic survey. In 1981, New Gold Inc. completed a program of geological mapping and prospecting in the area as the Sherk and Widow claims. In 1984 and 1985, Imperial Metals Corp. completed a program of soil geochemical sampling and a ground electromagnetic survey on the area as the Whymp 1-2 claims.
In 1990 and 1994, New Gold Inc. completed programs of geological mapping and a ground geophysical surveys on the area as the Widow 3-8 claims. In 2008, Cuda Capital Corp. completed a program of helicopter-borne magnetic and VTEM surveys on the area as apart of the El Capitan Property.
CHERYL MINFILE (092C 136)
The Cheryl occurrence is located 30 kilometres southwest of Nanaimo at the headwaters of Chemainus River on Mount Whymper.
The area, within the Cowichan uplift, is underlain by Mississippian to Pennsylvannian Fourth Lake Formation (Buttle Lake Group) sediments and Upper Triassic Karmutsen Formation (Vancouver Group) volcanic rocks whcih have been intruded by dioritic to granodioritic rocks of the Early to Middle Jurassic Island Plutonic Suite.
Outcrops on the claim host pyrite and chalcopyrite mineralization. Magnetite was observed in silt samples. A silicified chert and turbidite outcrop (OC4), hosts a quartz vein 1.5 metres long and up to 0.3 metres wide. Mineralization increases close to the vein but it appears that the wallrock contains more mineralization than the vein. Small shear zones with limonitic staining were also noted.
In 1981, New Gold Inc. completed a program of geological mapping and prospecting in the area as the Sherk and Widow claims. In 1984 and 1985, Imperial Metals Corp. completed programs of soil sampling and a ground electromagnetic survey on the area as the Whymp 1-2 claims. In 1988, the area was prospected and rock sampled as the Cheryl claim. A sample of outcrop (RS-15) containing 5 to 10 per cent pyrite and 3 to 5 per cent chalcopyrite assayed 0.14 grams per tonne gold and 9.6 grams per tonne silver (Assessment Report 18598).
In 1990 and 1994, New Gold Inc. completed programs of geological mapping and a ground geophysical surveys on the area as the Widow 3-8 claims. In 2008, Cuda Capital Corp. completed a program of helicopter-borne magnetic and VTEM surveys on the area as apart of the El Capitan Property
COTTONWOOD MINFILE (092C 242)
Cottonwood and Widow Creeks flow south off of El Capitan Mountain to the north shore of Cowichan Lake.
The area is underlain by Upper Devonian McLaughlin Ridge Formation (Sicker Group) mafic volcanics, Mississippian to Pennsylvanian Fourth Lake Formation (Buttle Lake Group) ribbon cherts and crinoidal limestone and basaltic volcanic rocks of the Upper Triassic Karmutsen Formation (Vancouver Group) to the north. These have been intruded by gabbroic to dioritic intrusives of the Late Triassic Mount Hall Gabbro and granodioritic rocks of the Jurassic Island Plutonic Suite. A major anticline occurs to the east and the area is highly faulted.
Placer gold is reported to occur in the head waters of Cottonwood and Widow Creeks. This could be related to known gold-copper quartz vein occurrences such as the El Capitan (MINFILE 092C 019) prospect.
It appears that most of the gold was derived from bars or in crevices in the bedrock of the river bed, or from benches along the side of the creek.
In 2008, a 1 by 2 by 0.5 metre pit was excavated, in the head waters of Widow Creek. Sluicing of the material yielded fine gold and a number of small flakes (Assessment Report 30172).