Antrim Project, Northern Territory, (final) relinquishment report for Exploration Licence 22645

Abstract

Geochemical evidence from whole rock analyses of Antrim basalts show that they are markedly depleted in Ni, Cu, and PGE throughout the province and throughout the stratigraphic section. Further the analytical data show that the basalts are strongly contaminated by crustal material. Basalts associated with the giant Noril'sk Ni-Cu-PGE sulphide deposits also show these geochemical features which are intimately tied to the magmatic ore forming processes. As at Noril'sk, the Antrim basalts were extruded through flat lying epicontinental sedimentary sequences that include some sulphur-bearing mudrocks. Contamination of the magma by these rocks may have been the trigger for sulphur saturation and sulphide formation within the basaltic melt. As at Noril'sk such sulphides may be concentrated in trap sites within the magma plumbing system located within the sedimentary successions immediately below the Antrim basalts. Interpretation of available geological and geophysical data over the Antrim Province has identified the NNW trending Neave Fault as potential fissure eruption sites for Antrim magma. Other NNW-trending faults are also potential feeder conduits. Magnetic anomalies located close to these structures may reflect intrusions near the base of the basalts related to the outpouring of the Antrim basalts. The Antrim Project tenements cover such targets along the Neave Fault. No exploration was carried out on the ground within EL 22645 with such activity been undertaken on other tenements within the Antrim Project area.