Cobar District: Mineral System Petrophysics Across Scales

A key exploration challenge in the Cobar region is the dominance of remnant magnetisation; characterisation of this and its relationship to the mineral system will provide new insights into the exploration methodologies required at the camp scale for this NDI area. Cobar-type systems are highly conductive to magnetic exploration (Wilkes, 1979), but are distinct from most other magnetite-bearing deposits, because they contain large volumes of pyrrhotite which is anomalously conductive/ chargeable, and also displays remanent magnetisation (in the monoclinic form). This study, which is in collaboration with the MinEx CRC and NSW Geological Survey, will utilise petrophysical techniques to constrain 3D conductivity magnetic and gravity modelling. It will integrate magnetic fabrics at the core scale with regional geophysical interpretation, providing insights into the formation of this enigmatic class of deposit. It will investigate the benefits and pitfalls of different methodologies for the collection of petrophysical data.