Gloucester Basin

The Gloucester Basin is a relatively small Permian sedimentary basin, approximately 40 km long and 10 km wide with a total area of 380 km2. The basin occupies the northern end of the north-south trending Stroud-Gloucester Syncline, about 100 km north of Newcastle.

The Gloucester Basin contains about 4,000 metres of sedimentary rocks. There are three major stratigraphic units in the basin. The Early Permian Stroud Volcanics/Alum Mountain Volcanics contains a sequence of volcanic rocks, fluvial deposits and coal. This unit is overlain by Late Permian Dewrang Group and the Gloucester Coal Measures. The Dewrang Group is about 600 m thick and contains fluvio-deltaic deposits with coal seams up to 10 m thick.