EL 2878 Rockhampton Downs, NT Final report.

Abstract

Ground magnetic surveys arid a review of other exploration and research data indicate that the potential for copper and gold mineralisation of the Tennant Creek type is too low to warrant further exploration. The exploration objective was to test the potential for copper/gold mineralisation of the Tennant Creek type. Regional magnetic data indicate that a zone of relatively shallow magnetic basement is present in the western part of the area. Extrapolation Of regional magnetic and gravity features into the area suggests that the shallow magnetic basement may be Warramunga Group sediments and volcanics. A compilation of water bore information was made to determine if any bores had intersected Precambrian sediments. The distribution and final depth of bores in the area and a summary of the driller's log for two of the deeper bores are shown in the company report. Five regional/semi-detailed ground magnetic traverses were completed to enable ground location and preliminary investigations of a prominent magnetic ridge in the western part of the licence. A total of 42.1 line-km was completed on the five traverses. Station spacing employed was 50 and 100 metres. The location of these traverses is shown in an overlay in the company report. rofiles showing the total magnetic field are shown for each traverse in Figures 4-7. Examination of these profiles indicates a depth to magnetic source of the order of 400m. Some variation in this depth estimate is apparent but none of the profiles are considered to represent the response of Warramunga Group sediments containing significant magnetite ironstones. The Rockhampton Downs licence area is considered to be underlain by Upper Middle Proterozoic Upper McArthur Group sediment not Lower Proterozoic Warramunga Group. As such the area is not prospective for copper-gold mineralisation of the Tennant Creek type.