Speden, I.G. 1971 Geology of Papatowai subdivision south-east Otago. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey bulletin 81 166 p.
Abstract: Papatowai Subdivision, south-east Otago is some 150 square miles in area and includes all Woodland Survey District, much of Rimu and Tautuku survey districts. Catlins district is a local name applied to an arbitrarily defined area, approximately that between the Catlins and Tahakopa Rivers, and comprising the central and major part of the subdivision. Mixed farming is the prinicpal occupation and is concentrated mostly on valley floors or on gentle dip slopes, from where the forest has been most easily cleared. Sawmilling is the only industry of any significance. No deposits of economic value occur in Papatowai Subdivision. Ironstones are not present in sufficient quantity (Willett, 1942): and the carbonaceous beds are unlikely to develop into workable seams and are of no commercial value. No limestone was found, and suitable material for roading is difficult to procure as most sandstones are cemented by zeolites and quickly disintegrate on weathering. Some gold was obtained from blacksand on beaches, especially from Wallace Beach to the west of the subdivision, but proved to be an uneconomic proposition and mining was soon abandoned. The gold was probably derived from ironstone and blacksand bodies common in the very shallow-water sediments in the vicinity.