Building a 3D Geomechanical Model for the Fitzroy Trough. Issue 1 (1st December 2019)

• Record Type: Journal Article
• Authors: Gaede, Oliver; Ziegler, Moritz; Heidbach, Oliver
• Is Part Of: ASEG Extended Abstracts (Online). Volume 2019:Issue 1(2019)
• Page Start: 1
• Page End: 4
• Publication Date: 2019-12-01
• Subjects: Numerical Geomechanics -- In-situ Stresses -- Canning Basin -- Fitzroy Trough -- Finite Element Method; Prospecting -- Geophysical methods -- Periodicals; Prospecting -- Geophysical methods; Periodicals
• DOI: 10.1080/22020586.2019.12073133
• Languages: English
• ISSNs: 2202-0586

Abstract

Summary: We present initial results from a physically self-consistent 3D geomechanical model for the Fitzroy Trough in the Canning Basin, Western Australia. Our research aims to improve the understanding of in-situ stresses in the trough, in particular the overall stress regime and spatial changes of the stress magnitudes due to basin geometry. We investigate the in-situ stresses first by utilising the classic "one-dimensional" approach to geomechanics and second by building a 3D geomechanical-numerical model. The boundary conditions of the 3D model are calibrated against stress data from wells within the trough. We show that the resulting overall stress regime is most likely strike-slip, although stress data from a small subset of wells would suggest a reverse faulting regime when considered in isolation. Further, basement depth and distance to basin boundary influence the stress magnitudes and lead to significant lateral variability of the stress magnitudes.