Annual report on EL 4871 Mt Tymn West, for period ending 20 March 1989

Abstract

Mt Tymn West - EL 4871, granted on 20 March, 1986 forms part of a Joint Venture agreement between The Metals Division of The Shell Company of Australia Limited, Billiton Australia and Mr G. Hamilton of Queensland. Billiton Australia are managers and operators of the Joint Venture. The geology is poorly exposed in the western portion of EL 4871 due to extensive alluvial cover. Whereas on the eastern boundary of the license, which lies on the western flank of the Mt Tymn ridge, bed-rock is well exposed. It comprises of coarse to medium grained sandstone, fine standstone and siltstone of the Early Proterozoic Burrell Creek Formation with bedding striking NNW and steep easterly dips. Gold mineralisation on Mt Tymn is hosted in sheeted quartz-limonite veins and fine limonite veinlets in the more competent, coarse grained lithologies of the sedimentary package. Veins are generally subparallel to bedding although minor cross-cutting vein systems have been recorded. Grid-based soil sampling over Mt Tymn defined two gold-bearing anomalies within EL 4871. The first anomaly (max. 121 ppb Au) trends NNW over 150m on the northern extension of the ridge. This anomaly is confirmed by rook chip samples which returned grades of up to 7.25 g/t Au. The second soil anomaly (max. 62.7 ppb Au) occurs at the base of the Mt Tymn ridge, in the drainage path of old gold workings. This anomaly reflects transported gold-bearing gravels and scree rather than in situ gold mineralisation. A soil sampling programme is presently being undertaken on a low NS-trending ridge of out-cropping Burrell Creek Formation, immediately east of the Stuart Highway.