Geological Setting of Volcanogenic Massive Sulphide Occurrences in the Middle Paleozoic Sicker Group of the Southeastern Cowichan Lake Uplift (NTS 092B/13), Southern Vancouver Island

Volcanogenic strata of the mid-Pa leo zoic Sicker Group on Van cou ver Is land (Fig 1) host the world-class Myra Falls volcanogenic mas sive sul phide (VMS) de posit (com bined pro duc tion and proven and prob a ble re serves in ex cess of 30 mil lion tonnes of Zn-Cu-(Au-Ag) ore), as well as nu mer ous other VMS de pos its and oc cur rences, es pe cially in the Big Sicker Moun tain area in the south east ern part of the Cowichan Lake up lift (Fig 1). Three of these de pos its, the Lenora, Tyee and Rich ard III (MINFILE oc cur rences 092B 001, 002, 003) have seen lim ited his tor i cal pro duc tion, and the Lara de posit (MINFILE oc cur rence 092B 129), far ther to the north west, also con tains a sig nif i cant drill-in di cated re source. Geo log i cal map ping (Massey and Fri day, 1987) sug gests that the Big Sicker Moun tain area is un der lain mainly by de formed mafic to fel sic vol ca nic and volcaniclastic rocks of the Nitinat and McLaughlin Ridge for ma tions and high level in tru sions of the Saltspring in tru sive suite, as well as abun dant gabbroic dikes and sills of the Tri as sic Mount Hall gab bro. Log ging ac tiv ity in the Big Sicker Moun tain area over the past de cade has pro vided abun dant new out crops and prompted a re-ex am i na tion of the geo log i cal set ting of VMS min er al iza tion and of the po ten tial for new dis cov er ies in this area. This re port pres ents a pre lim i nary ver sion of a re vised geo log i cal map of the Big Sicker Moun tain area, as well as new lithogeochemical and U-Pb zir con geo chron ol ogy re sults that bear on the geo log i cal set ting of VMS min er al iza tion in the south east ern Cowichan Lake uplift, as well as the potential for new discoveries in the area.