1970 Progress reports for AP 2162 Perenti Copper Prospect

Abstract

Progress Report for November, 1969 - In the current drilling programme, DD NT-12-l was completed on 25th October at 418 feet. DD NT-12-2 was collared on 26th October and completed at 613 feet 5 inches on 4th November. DD NT-12-3 was collared on 8th November and at the 24th was drilling to 486 feet in reef quartz. The core of DD NT-12--2 was split between 436'6' and 498'6' (16 samples) and dispatched for Cu assays and Pb, Zn, Ag and Au analyses. Sludge samples between 380 feet and 613 feet 5 inches, 23 samples were dispatched to Geomin for Cu, Pb, Zn, Ag, and Au analysis. The abridged log of DD NT-12-2 is as follows; 0' 436'l' Foliated granite: Consists of pink orthoclase, white plagioclase and quartz augen separated by biotite, chlorite and laminae defining foliation. 463'l' 446'8' Breccia: Chlorite - hematite matrix enclosing red feldspar and quartz fragments 2mm to 10cm in diameter. Original foliated structure lost. Cut by thin quartz veins containing chalcopyrite and pyrite. 446'S' 466'5' Quartz reef: Grey to green chlorite - quartz breccia to 425 feet. Grey to white quartz 452 to 460 feet contain in disseminated grains of chalcopyrite of variable grainsize. Total suiphide rarely greater than 2%. 460 to End, darker green and grey coloured reef. Occasional fluorite matrix for white quartz breccia. 15th Progress Report December, 1970 - I wish to advise that Central Pacific Minerals NI and its co-holder in the Authority to Prospect, Magellan Petroleum (NT) Pty Limited, do not intend to apply for renewal of AL 2162. The results of our investigation have not been encouraging although three holes put down intersected low grade copper mineralisation. A completion report will be prepared for submission to you during the present summer season. Progress Report January 1970 - Analytical and assay results have been received from Geochemical and Mineralogical Laboratories. Copper assays over a true width of 39 feet average 0.5%. Atomic absorption results over the same length for lead, silver, zinc and gold were all low. Lead and zinc values were less than fifty parts per million and silver and cold values were less than 0.5 dwt/ton. Progress Report for May, 1970 - The Perenti induced polarization reconnaissance survey commenced on 22nd May, was completed one week later. Results have not yet been sighted. Investigation of the Perenti prospect involved an examination of approximately 60,000 feet along a shear zone or lineament along which quartz veins containing disseminated boxworks and weak copper have been found. It was considered that should significant mineralization occur along this structural feature it would be in the form of sulphide-rich shoots pitching steeply within the main body of the quartz veins - individual shoots would probably be a few hundred feet in length and several to a few tens of feet thick. To search for this type of mineralization using conventional grid coverage would require numerous IP traverses, much of which would be over barren ground on either side of the quartz-veins. A single longitudinal induced polarization traverse with set-up points within fifty feet of the suspected outcrop or projected mineralized zone was therefore planned, using 300 foot spreads. This method allowed for rapid, economical and complete coverage of the potential ore-bearing zone and on either side of the wall rocks for a distance of seven hundred feet. Progress Report for September, 1970 - The area of anomalous response on Line DDH 3 of the induced polarization survey carried out at

Perenti earlier this year was examined. It was not attributable to any obvious geological feature. Granite was the only rock type exposed on each of the lines examined. The report by the contractors, McPhar Geophysics, is still awaited.