| Title | Geothermal Prospectivity of the Mountain Bridge Area, North Perth Basin, Australia |
|---|---|
| Authors | Mark BALLESTEROS |
| Year | 2015 |
| Conference | World Geothermal Congress |
| Keywords | hot sedimentary aquifers, fracture permeability, reservoir identification, prospect identification |
| Abstract | The North Perth Basin (NPB) in Western Australia offers one of the most attractive areas for geothermal exploration in Australia. Key geological ingredients for a working geothermal system include a heat source and a heat trap in the form of thermally insulating rocks such as coals or low thermal conductivity shales with underlying naturally permeable, cavernous or fractured reservoir rocks (Cooper and Beardsmore, 2008). Available data suggests that the NPB has all of these attributes and is also located close to a market with increasing demand for energy. The technical evaluation of the NPB has identified a number of attractive target areas, with permeability associated with open natural fractures providing the most attractive potential reservoir. Exploration to date has focussed on areas with 3D seismic data coverage, which provides superior ability to identify and evaluate natural fracture systems. However, a recent review of the geothermal prospectivity outside the areas with existing 3D seismic data coverage has revealed an outstanding geothermal prospect. The potential is highlighted by the results of the petroleum exploration well Mountain Bridge-1, which flowed 146 degreeC water from the interval 3185-3235m at approximately 4 l/s. Available data from the well indicates the water came from natural fractures within the Permian High Cliff Sandstone. A 3D seismic survey is currently scheduled for acquisition in late 2014 as part of the petroleum exploration efforts in the area. This data set will facilitate the evaluation of the geothermal potential of the area when it becomes available, and will hopefully provide a means of identifying and assessing the faulting and associated fracture systems that could provide an extensive and effective geothermal reservoir. |