4D Evolution of Salt Diapir Reactivation and Normal Faulting in an Oblique Extensional System: Insights from 3d Seismic Interpretation and Scaled Physical Modeling from Vulcan Sub-Basin, NW Australia
Long Wu
Geology and Geological Engineering, Colorado School of Mines, Golden, CO, USA
[email protected]
Abstract
In this study, an oblique extensional system with one reactivated salt diapir in the center was identified from Vulcan Sub-basin, NW Australia, and a detailed 3D structure model had been built based on the interpretation of high-quality 3D seismic data. The normal fault system developed from two phases of extension with differing extension directions. The orientation of first-phase normal faults largely controlled fault development during the second-phase of extension, and the salt diapir reactivated during the second-phase of extension changed the local structural styles profoundly. These controlling factors contribute to the uniqueness and complexity of this system. In order to better understand a) the kinematic deformation process, and b) how pre-existing structural fabrics and salt diapirs influence the formation of normal fault system, I aim to conduct a series of scaled physical models with different configurations and parameters. State-of-the-art monitoring systems will be utilized for time series analysis of normal fault system development. Serial sections in each model will be cut parallel to the extension direction to a) investigate the structural variation along the strike, and b) reconstruct normal fault system in a 3D volume which will be analyzed and compared with 3D seismic interpretation results. Physical models with different configurations will be compared to study the mechanical roles of pre-existing structural fabrics and salt diapir during the deformation. This project will provide a comprehensive understanding of the 4D evolution of this system as a result of integrating 3D seismic interpretation and physical modeling results.
AAPG Search and Discovery Article #90199 © 2014 AAPG Foundation 2014 Grants-in-Aid Projects