The Application of Dual Frequency IP Survey to Identify the Concealed Ore Body in Pilbara Craton, Australia: A Case Study from Calvert Gold Deposit

Abstract

The Mallina Basin in Western Australia, situated in the central part of the Pilbara Craton which is one of the world's oldest cratons, is a structurally deposited basin subjected to multiple episodes of deformation and magmatic intrusion. The Calvert gold deposit in Mallina Basin is heavily covered by Quaternary, thus, it is hardly to identify any distinct mineralization indicators, and there is no any significant progress in exploration so far. The SQ-3C dual frequency induced polarization facility that is developed by China is introduced to carry out the dual frequency IP survey, the author’s team have tested all the types of different rock samples to collect the geophysical parameters in the Calvert area, and the selection of suitable facility and working frequency is based on the geological characters of the Calvert deposit and the geophysical parameters of rocks, and some processes are undertaken to weaken the interference triggered by the electromagnetic coupling, and an IP anomaly zone was delineated. Through the drilling program in the IP anomaly zone, a gold ore body that has the same orientation with the IP anomaly zone was controlled; this result demonstrated the dual frequency IP survey is effective in the local area and provide an efficient technical method for the mineralization prospecting, and this geophysical survey project sets an example for the familiar type of gold deposit in the local area.