Miocene to Pleistocene basaltic rocks of the Chilcotin Group cover bedrock prospective for porphyry Cu-Au mineralization over a large area of south-central British Columbia and has provided significant challenges to exploration in these areas. Geoscience BC Report 2013-17 presents the findings of a study aimed at identifying deep penetrating geochemical techniques potentially capable of detecting mineralization under basalt cover.
Samples have been collected over known porphyry style Cu-Au mineralization at the Deerhorn and Three Firs prospects in the Woodjam Area (Minfile No. 093A 078). In both areas, Chilcotin Group basalt cover occurs adjacent to concealed mineralization at at Three Firs an angled drill hole intersected basalt before hitting mineralization.
A variety of sample media have been collected, including Ae-horizon and B-horizon soils, spruce bark and spruce twigs as well as a limited number of clay and carbonate amygdules in basalt. Electrical conductivity, pH, H+ and H+a measurements were performed on Ae- or upper B-horizon soils whereas B-horizon soils have been analyzed using seven different leach techniques.
Field components of this study were undertaken in conjunction with Geoscience BC Project 2012-001 entitled: "Evaluation of plant exudates to assist in mineral exploration and the development of simple and cost effective field procedures and analytical methods"