Onshore exploration – both oil and gas and geothermal – typically involves the mobilisation of full sized conventional rigs. The support package includes back up and auxiliary parts, capable of drilling and fully evaluating deep large diameter conventional holes. In early stage exploration programs conducted in remote and frontier locations, the operating costs can approximate those of an offshore operation. This standard approach may be an unnecessary expense and lessons can be learned from the mining industry, which has been operating in a lower cost environment in frontier locations for over 125 years. A slim well approach is adopted not just to the well design but to team size, civil works, evaluation requirements and logistics. A smaller rig capable of drilling slim wells to the desired terminal depth (of up to 4,000 m), with complete logging and core sampling, can provide exploration companies with a cost effective solution.