GEOLOGY AND EXPLORATION HISTORY OF THE AMALGAMATED KIRKLAND DEPOSIT, KIRKLAND LAKE, ONTARIO

The Amalgamated Kirkland gold deposit is located at Kirkland Lake, Ont ario, within the Archean Abitibi Greenstone belt of the Canadian Shiel d. It lies on a fault or ''break'', termed the Cyprus Break, which is a splay off a regional structure termed the Cyprus-Battle Mountain Bre ak. The Cyprus Break merges with the Cyprus - Battle Mountain Break ab ove the -250 m level, as it was not encountered in shallow drilling or surface exploration. These structures lie 1.5 km south of the 727 000 kg (23 million ounce) Kirkland Lake Main Break and 0.5 km north of th e 872 000 kg (30 million ounce) Larder Lake Break. The deposit is host ed by alkalic Timiskaming Group volcanic and sedimentary rocks which a re overthrust by older Larder Lake Group tholeiitic and komatiitic flo ws along the Larder Lake Break. Timiskaming syenitic intrusives, simil ar to the host rocks for the Kirkland Lake Main Break gold deposit, in trude both suites. The Amalgamated Kirkland deposit consists of lode-s tyle gold mineralization which is mainly hosted by altered and pyritiz ed Timiskaming trachytic volcanics which wedge out or thin at depth, b etween two sedimentary units. The intersection of the Cyprus - Battle Mountain and Cyprus Breaks, in conjunction with the westward plunge of the volcanic wedge, appears to control the westerly plunge of the Ama lgamated Kirkland deposit at approximately 50 degrees. Mineralization is characterized by blue-gray brecciated and ''wormy'' quartz-ankerite veins which contain up to 10% fine-grained pyrite and, in decreasing order of abundance, minor galena, chalcopyrite, sphalerite, molybdenit e and visible gold. The sulfides and gold commonly occur along fractur es and wallrock inclusions within the veins. Native gold occurs as fin e pinpoints distributed in 1-mm to 5-mm size clusters of up to ten or more grains. The auriferous veins occur within a quartz-ankerite-seric ite-pyrite alteration assemblage which is enveloped by a broader zone of ankerite-sericite+/-hematite+/-quartz-pyrite alteration up to 60 m wide. This latter assemblage overprints the regional greenschist-facie s chlorite-calcite assemblage. The Amalgamated Kirkland property has h ad a long history of exploration activity beginning with the first dis covery of mineralization in 1911 on the Hunton Shaft claim located in the northeast corner of the property. Since that time various prospect ing, mapping, trenching, geophysical surveys and diamond drilling prog rams have concentrated on either carbonate zones along the Larder Lake Break or quartz veins along the northern side of the property in asso ciation with complex trachyte flows and syenite dikes. Battle Mountain Canada Inc. located the Cyprus - Battle Mountain Break through a pros pecting, trenching and geophysical program in 1989. Drilling by Battle Mountain and Cyprus Canada under the surface showing, coupled with se veral revisions to the structural interpretation of the Cyprus Battle Mountain and Cyprus Breaks, resulted in delineation of the Amalgamated Kirkland deposit. Location of an auriferous structure through basic s urface exploration within 1 km of a world-class orebody demonstrates b oth the subtle nature of Archean gold deposits and the potential for f inding new mineralization in heavily prospected camps.