Journal of Petroleum Geology, vol. 21(4), October 1998, pp. 445-465

DIAGENESIS AND RESERVOIR DEVELOPMENT OF SANDSTONES IN THE TRIASSIC REWAN GROUP, BOWEN BASIN, AUSTRALIA

A. Bashari*

The non-marine Lower Triassic Rewan Group in the Bowen Basin, Australia, is mainly composed of lithic arenites containing high proportions of volcanic rock fragments.Sublitharenites are also present. The arenites are cemented by abundant authigenic quartz, carbonates and clay minerals. Three separate lithostratigraphic intervals can be identified: a conglomeratic unit at the base; a sequence dominated by lithic arenites in the middle; and a section dominated by sub-litharenites at the top. Petrographically, the sandstones can be divided into a facies whose quartz content is greater than 75% on a QFR diagram; and a labile or lithic facies which contains less than 75% quartz. There is a progressive change in clay mineral assemblage from one petrofacies to the other.