Do numerical models produce realistic fault evolution patterns?

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Rifting of continents to produce new ocean basins is an important part of plate tectonics, and the geometry and magnitude of stretching has many implications for the development of hydrocarbon systems. Over the last decade numerical models have provided crucial insights into the rifting process, mainly using low-resolution 2D models. With advances in computational power it is now possible to numerically model rift evolution at a high-resolution in 3D to model how rift-scale fault arrays during rifting nucleate, propagate and grow through time. However, there are few observations of how normal fault arrays evolve at the rift scale to quantitatively test if the modern numerical models are producing fault array evolution predictions that are geologically realistic. This PhD will focus on quantifying the geometry and displacement history of fault arrays over complete rifts using large compilations of 3D seismic reflection and well data from data-rich and well-studied rifts such as the North Sea and NW Shelf of Australia. This will then be compared with the results produced by the 3D numerical model in order to test if it is geologically realistic. The key outcome of the PhD will be a better understanding of how fault arrays during early continental rifting (beta factors < 1.5) evolve at the rift scale. A newly validated numerical model of fault arrays in rift basins will be greatly applicable to other rift systems with sparsely populated data, covering a range of scales between regional large scale fault evolution systems, to mesoscale field outcrops and analogues, to the microscale using core and well image logs. This can provide better fault predictions on frontier regional seismic data, as well as establish sub-seismic fault density for fault seal analysis, ultimately reducing uncertainty in an extensional fault regime.