An area located 50 km north-northeast of Wudinna, and situated on the southern margin of the Gawler Ranges, has been explored for possible economic deposits of both Olympic Dam style epithermal copper-gold-uranium and Tanami style orogenic lode gold, and latterly also for possible Tertiary roll-front style sedimentary uranium mineralisation. It was postulated that the thick lava flows of the Mesoproterozoic upper Gawler Range Volcanics may have formed a seal for later generated, outwardly migrating mineralising fluids. On the regional aeromagnetic images, zones of demagnetisation evident along linear structures and flow fronts suggested that there has been considerable magnetite-destructive alteration occurring during escape of these fluids from the sealed system. It was believed that this setting has the potential to form large gold deposits due to the focussing of mineralising fluids over a long time span. Marmota Energy as uranium exploration operator commissioned the flying of an aerial EM survey (25 Hz TEMPEST) during June 2008 to try to better outline the channels of a palaeodrainage system indicated on existing airborne radiometric data. In total 1745 line km of profiles were flown covering the entire licence area, along 400 m spaced east-west lines with a sensor height of 220 m. Some conductive sediments that are thought to belong to the Thurlga Palaeochannel were interpreted, but their perceived prospectivity for hosting sedimentary uranium mineralisation appeared to be low by comparison with that of palaeochannels identified on Marmota's other project acreage in the Gawler region. No other exploration was conducted on the relinquished western portion of EL 3458. The majority of this area overlaps the Gawler Ranges National Park, and was deemed difficult for exploration due to land access restrictions.