Mapping Northern Australia’s Present Day Stress Field: The Canning Basin

Abstract

The Canning Basin of Western Australia has recently become a site of interest for unconventional hydrocarbons, with several formations within deeper basin depocentres being investigated for resources. Modern petroleum resource evaluation is generally dependent on an understanding of both local and regional stresses, as well as the geomechanical properties of reservoir units. Presently, there are significant gaps in our understanding of these factors within the Canning Basin. This study is part of a greater effort from Geoscience Australia to understand the present-day stress field of northern Australia. A generally NE-SW oriented maximum horizontal stress azimuth is identified from interpretation of borehole failure in five petroleum wells, and a broadly strike-slip faulting stress regime is interpreted from wireline data and wellbore testing. Variations in stress regime at different crustal levels within the Canning Basin are highlighted by one-dimensional mechanical earth models that show changes in the stress regime with depth as well as by lithology, with a general move towards a normal faulting stress regime at depths greater than ~2.5 km.