Gold mineralisation at the Tarcoola prospect occurs within quartz veins occupying extensional fractures and faults cutting through the quartz sandstone and claystone of the Late Proterozoic Tarcoola Formation. Most of the past gold production has been from discrete quartz veins averaging 0.3 m wide, but zones of small quartz veins, each generally less than 1 cm, also contain gold in places. The current exploration will target lower grade mineralisation than that found in the large quartz veins, and will also investigate possible southern extensions in an area of no outcrop to the south of the Pug Seam Fault.