Crude oil and potential source rock studies in the Eromanga Basin

Hydrocarbon deposits occur at a number of stratigraphie levels within the Cooper/Eromanga Basin sequence in Australia. Sedimentary sequences contained in the Permo-Triassic Cooper Basin sequence are mainly fluvial and lacustrine in origin. Continental type sediments are predominant in the lower part (Jurassic) of the overlying Eromanga Basin sequence. The lower part of the Cretaceous is mainly shallow marine and grades up through a paralic sequence to a thick succession of fluvial origin. Organic petrological studies show that the Permian section in the Jackson/Naccowlah area has very good source potential and that the source potential is poor to fair in the Mesozoic section. In contrast, the Mesozoic section, particularly the lower part, has a very good source potential in the Merrimelia/Packsaddle area, where very little, or no, Permian section is preserved.