The mineral occurrences in this area are in the footwall of a major low-angle thrust fault. The hanging wall of the thrust is composed of argillite and graywacke of Jurassic to Cretaceous age (Clautice and others, 1989, plate 1). The footwall host rocks of the mineral deposits are mainly highly faulted andesite-basalt of probable Late Triassic age. A pyritic felsic body has been emplaced along the thrust (?) fault in this locality (Clautice and others, 1989).

Clautice and others (1989) described the following deposits (localities 1 to 3): quartz-carbonate veins in brecciated greenstone assayed as much as 1,880 parts per billion (ppb) gold, 1,080 parts per million (ppm) lead, and 5,990 ppm zinc. Although galena and sphalerite are not reported at locality 1, the lead and zinc values indicate their probable presence. The deposit at locality 2 contains more than 1 percent copper in malachite-stained greenstone. The deposit at locality 3 contains abundant pyrite in greenstone; the pyrite is extensively altered to limonite, and chalcopyrite, azurite, and malachite are abundant locally. This last deposit is probably at the site reported by Clautice and others (1989) and Smith and others (1973) and by Cobb (1979 [OFR 79-238, locality 12, figure 4). It also probably corresponds to locality 13 of Nokleberg and others (1991, table 2), who reported the presence of bornite and iron-bearing carbonate minerals; a sample assayed 2.4 percent copper and 5 ppm silver. R.A. Blakestad (written communication, 1980) reported about 0.5 ppm gold in black Triassic argillite in the fault footwall of Jurassic argillite at sites close to those visited by Clautice and her associates.