Tectonics and Hydrocarbon Prospectivity Through the Integration of Airborne Gravity Gradiometer, Magnetic and 2-D Seismic Data in the Canning Basin, Western Australia

Abstract

In recent years advanced 3D seismic acquisition technologies like wide-azimuth and full-azimuth geometries are playing a vital role in the hydrocarbon exploration. The exploration costs of these methods are much higher than the potential field and 2-D seismic methods. In the present challenging economic times, there is a strong commercial driver to continue hydrocarbon exploration by more cost effective geophysical exploration methods. The obvious solution for achieving this task is potential field data acquisition and integration with other available data for a cohesive interpretation. We present a case history that describes how the potential field data not only improves the existing seismic interpretation but also minimizes the ambiguity of the interpretation. This study demonstrates how airborne gravity gradiometer data and magnetic data can be used in combination with 2D seismic data to obtain a much improved 3D understanding of the geological structure, sediment distribution, tectono-sedimentary evolution and hydrocarbon prospectivity of frontier basins in an effective and time-efficient manner. The study also shows examples of how the gravity gradient and magnetic data played a key role in revealing geological information that otherwise would be concealed with seismic data alone in this complex geologic setting. The Canning Basin in Western Australia, is a frontier basin and under-explored for hydrocarbons. The structural evolution of the Canning Basin is strongly influenced by pre-existing structures. An important aspect in the development of the onshore Canning Basin is that extensional deformation and subsidence, leading to the formation of depressions and sedimentation, were controlled by the reactivation of structures initially formed by Proterozoic orogenic phases. Most of the available information about the subsurface structure of this predominantly Palaeozoic basin is from 2D seismic data, mostly ‘vintage’ data. The integration of various data sets and the workflow of this study with various geophysical tools produced a robust geological model. This geological model defined the 3D distribution of lithological units, the fault structure and the geological evolution in particular, understanding the deep structure and its tectonic inversion improved the interpretation of the polyphase tectonic, inheritance of tectonic structures and the influence of structural evolution on sedimentation and hydrocarbon plays.

AAPG Datapages/Search and Discovery Article #90291 ©2017 AAPG Annual Convention and Exhibition, Houston, Texas, April 2-5, 2017