Cretaceous to Cenozoic sedimentary basins in Western Southland include a wide range of non-marine and marine sediments, in a structurally complex setting dominated by major fault systems. A reassessment of their mineral potential confirms large quantities of nonmetallic minerals (limestone, aggregate, marl), and smaller reserves of bituminous coal, lignite, clays, and oil shale._x000D_
Hydrocarbon potential is largely untested. Metallic minerals are present in trace amounts, apart from platinum group minerals and some detrital gold. In the offshore area, seismic data suggest the hydrocarbon potential is significant._x000D_
The Orepuki area has the most interest onshore.