Gloucester Basin

The Gloucester Basin contains up to 4000 metres of Permian sediments and acid volcanics. The Permian sediments are a complex mixture of coal seams and interbedded sandstones.

Location of the Gloucester Basin, New South Wales, Australia

The hydrogeology of the deeper Gloucester Basin in not well known with the average depth of groundwater bores within the Gloucester Basin only 21.8 metres with no bores deeper than 100 metres (NSW Groundwater Data Archive 2007).

However it is clear that there is significant surface-groundwater interaction within the Gloucester Basin with groundwater making up a high proportion of the flow (baseflow index 0.668) within the Gloucester River (Gauge 208020).  However there are still questions as to which aquifer this groundwater comes from, and what are the interrelationship with the coal seams and the groundwater.

Methane reserves in the Gloucester Basin are still being assessed, but 3P (Proved, Probable and Possible) reserves and better have been calculated at 15.4 billion m3/570 PJ/ 540 BCF (http://www.agl.com.au/Downloads/Gloucester_Project_overview.pdf). The Gloucester Basin has also received some interest as a potential site for geothermal energy (hot sedimentary aquifers).