The Knob Hill showing is located about 1.0 kilometre east of Anyox/Falls Creek, about 3.5 kilometres east of Anyox. It has been evaluated in the past for copper mineralization.
The region is underlain by a roof pendant, consisting of volcanic and sedimentary rocks, within the Eocene Coast Plutonic Complex. These pendant rocks have been correlated with Middle-Upper Jurassic Hazelton Group rocks and overlying upper Middle to Upper Jurassic Bowser Lake Group sedimentary rocks (Geological Survey of Canada Open File 3453). The Hazelton rocks consist of variably chloritized pillow and massive andesite and basalt with minor mafic tuffs. The overlying Bowser Lake sediments consist of argillite, siltstone and sandstone with minor chert and limestone. There are two observable phases of folding in the area, an initial north-northeast trending phase followed by a later east-northeast trending phase.
The showing is described as a disseminated pyrite zone developed in andesite (Assessment Report 3534). Mineralization of a number of deposits on the CD and CU claims (including Knob Hill) is generalized as being massive to disseminated pyrrhotite containing veinlets and dispersed blebs of chalcopyrite and pyrite (Minister of Mines Annual Report 1967, page 40).
D.J. Alldrick (British Columbia Geological Survey Branch) reports that the pyritic unit is a mappable volcanic breccia (regolith) that lies between underlying pillow basalts and overlying turbidites. The breccia matrix is composed of fine-grained pyrite and silica and appears to be a pyritic chert or sinter. The unit is 2 to 3 metres thick wherever observed. It has been exposed in a series of old trenches that removed overburden and blasted down into the bedrock. In this area, the contact strikes 055 degrees with a near vertical dip. Breccia clasts are subrounded to ovoid and range from 2 to 6 centimetres in length.
Alldrick deems this outcrop exposure significant because it represents a local depositional basin that accumulated and preserved regolith, silica and pyrite along the same horizon that hosts the Hidden Creek (Anyox) orebodies to the north (see 103P 021). Alldrick did not observe copper mineralization at this local and a grab sample he collected yielded only 0.0018 per cent copper.
The area was likely trenched during Cominco's extensive exploration programs in the early 1950s.