Oil shale of the Duaringa Basin, Central Queensland

Abstract

Exploration in the Cainozoic Duaringa Basin of Central Queensland in 1978–1980 led to the delineation of extensive oil shale deposits. The Basin is a north-northwest-trending half-graben, 180km long and up to 20 km wide, superimposed on the deformed eastern margin of the Permo-Triassic Bowen Basin. It contains up to 1300 m of flat-lying shales and sandy mudstones of fluvio-lacustrine origin. Oil shale of Middle to Late Eocene age occurs in two near-surface seams (the ‘resource seams’) and associated with lignite several hundred metres stratigraphically below the resource seams. The shallow seams are estimated to contain a potential yield of 3.7 × 10 9 barrels of shale oil at an average grade of 82 dm 3 tonne −1 at zero retort moisture (LTOM). The bulk of the resource is contained in the lower resource seam in three discrete areas.