The Big Bug occurrence is located at 1234 metres elevation 8.5 kilometres southeast of Baldy Mountain, in the former historic Camp McKinney. The Big Bug (Lot 923) Reverted Crown grant lies below the Minnie-Ha-Ha (Lot 680) Reverted Crown grant of the McKinney camp. The camp lies 9 kilometres north-northwest of Bridesville, British Columbia.
Development work began on the Big Bug occurrence in 1897 under the ownership of A. McGraw and W.H. Norris and continued until 1901. A 9.1-metre shaft was sunk on a small quartz vein striking 090 degrees. Apparently, no further work was done. The Big Bug property is now owned by W.G. Hallauer.
The Camp McKinney area is underlain by interbanded and intergrading Carboniferous to Permian Anarchist Group metamorphosed sediments and volcanics. The group is mainly sedimentary and consists of greenstone, locally calcareous, altered quartzite and argillaceous quartzite, greywacke, limestone and locally micaceous quartzite and calcareous biotite schist. The minor volcanics are described as mainly altered andesitic and basaltic flows.
Granite and granodiorite of the Middle Jurassic Nelson intrusions have intruded the Anarchist Group to the west and south as small stocks and plugs. Along the contacts of these intrusions the Anarchist rocks have been deformed and hydrothermally altered. Younger dikes of felsic and mafic composition intrude both stratified and granitic rocks and may have been associated with faults related to these granitic intrusions.
The major regional structural feature in the vicinity of the Cariboo-Amelia occurrence (082ESW020) is a northeast trending fault zone 5 kilometres to the east. The fault follows Conkle Creek, Conkle Lake and Jolly Creek.
Faulting in the Cariboo-Amelia mine area is postmineral and widespread. Major east-dipping, low angle thrust faults in the central portion of the mine have displaced the hangingwall to the northwest by about 122 metres. An east-dipping fault has also moved the hangingwall south by about 91 metres. The complexly faulted and folded rocks are predominantly northwest striking and steeply to moderately northeast dipping.
Outcrop is sparse on the Big Bug property. Calcareous greenstone is found in a few outcrops west of the old shaft. Alteration and shearing have given a weak schistose texture to the greenstone. The shaft was sunk on a 5 to 20 centimetre quartz vein striking 090 degrees and dipping 80 degrees south. The vein has been traced on surface, 10 metres west of the shaft. Pyrite occurs as fracture fillings and disseminations in the quartz vein. Four samples were taken from the Big Bug dump in 1991, however, assay results for gold and silver were not significant (Assessment Report 21464). Sample R2-91001WH yielded 0.07 gram per tonne gold. 4 grams per tonne silver and 0.03 per cent zinc (Assessment Report 21464).
