Relating Reactivation and Inversion on the Northwest Australian Shelf to Stress Regimes through Time

Scott Dyksterhuis, School of Earth Science, University of Sydney, Room 141, Baxter Building H11, School of Geosciences, University of Sydney, 2006, Australia, phone: +612 90366538, fax: +612 9036 6588, scottd@geosci.usyd.edu.au, Patrick Unternehr, Total, Paris, France, and Dietmar Mueller, School of Earth Science, University of Sydney, Room 145, Baxter Building H11, University of Sydney, 2006, Australia.

Data compiled as part of the World Stress Map project (Reinecker et al., 2005) provide important constraints on present orientation and magnitude of the maximum horizontal compressive stress regimes of continents. Understanding of palaeo-stress regimes is less well developed, however, since stress data can be sparse over large areas of continents and specifically over geologic time. Knowledge of palaeo-stress regimes is particularly relevant to the field of hydrocarbon exploration, since such knowledge allows for the creation of predictive frameworks for fault reactivation as well as for larger, basin scale inversions.

Extension on the North West Shelf margin has been influenced by pre-existing structure and continental lineaments (Elliot, 1994) with the prevailing fault strike on the North West Shelf being NE-SW. Many authors have highlighted the importance of light, oblique reactivation to the economic importance of petroleum traps on the North West Shelf. Using methods developed for modelling the stress regimes of continents and plates for the present day and through geologic time (Dyksterhuis et al., 2005), we have examined various tectonic reactivation and inversion events over the Australian North West shelf with respect to modelled palaeo-stress regimes since the early Cretaceous.

References

DYKSTERHUIS, S., ALBERT, R. A. & MÜLLER, D. (2005) Finite element modelling of intraplate stress using ABAQUS™. Journal of Computers and Geosciences, 31, 297-307. ELLIOT, C. I. (1994) Lineament Tectonics: An approach to basin analysis and exploration. IN PURCELL, P. G. & PURCELL, R. R. (Eds.) The Sedimentary Basins of Wets Australia. Perth, Petroleum Exploration Society of Australia Symposium. REINECKER, J., HEIDBACH, O., TINGAY, M., SPERNER, B. & MÜLLER, B. (2005) The release 2005 of the World Stress Map (available online at www.world-stress-map.org).

Basin Modeling Advances
2006 AAPG International Conference and Exhibition, (November 5-8, 2006) Technical Program