17th Annual report on the evaluation of Coxco lease AN 366, Emu Fault Zone

Abstract

The Coxco Prospect, AN 366 is located approximately 10 kilometres southeast of the HYC deposit. It is a sub-economic carbonate hosted, Zn- low Pb deposit within highly prospective Proterozoic McArthur Group stratigraphy directly adjacent to a major regional structure, the north-south trending Emu Fault zone. Mineralisation exhibits both stratabound and structurally complex, fracture controlled characteristics within both sedimentary breccias and massive dolomite tectonic breccias respectively. A highly irregular, cavitated, karstic weathering profile, within which conventional drilling techniques have failed to adequately recover oxide sample material, further complicate a deposit which has confounded multiple campaigns of evaluation spanning over 90 years. In the reporting year 2008-2009, work focussed on refining the geological block geometries utilising detailed drill section information gathered during the North Ltd drilling (1999-2001). This work was designed to aid additional drill targeting for a 2009-2010 diamond drilling program. In addition, North Ltd detailed surface mapping (Selley, 1999) was registered to provide some surface constraint to fault, stratigraphic, base of oxidation and base of Cambrian Bukalara Sandstone 3D geometries. In detail: Nine sections were structurally re-interpreted; These nine sections were digitised and registered within the VULCAN Coxco model; Selley's (1999) interpretive map was draped on topography within the VULCAN Coxco model; Important surfaces were re-interpreted and triangulated using the new section and surface constraints. These included: 3 strands of the Emu Fault Zone, the Coxco Fault, a NW-SE Fault that cuts the Emu Fault Zone just south of Cook's', the base of Barney Creek-Lynott Formations (top of 'Coxco Dolomite' Member), the base of oxidation and the base of the Cambrian Bukalara Sandstone. Detailed review of all the historic drilling results in the context of the new sub-surface geometries highlighted sections for infill and/or extension-to-depth drilling. Potential drill targets and the two highlighted targets on sections 2950N and 2775N were chosen for 2009-2010 drilling.