The model demonstrates that subsidiary faults in the hanging wall may significantly influence the construction of the master listric fault geometry at depth. Negating heave/extension by the subsidiary faults can result in an under-estimation of the amount of extension and hence an over-estimation of the depth to the main fault plane, with the error in the depth calculation increasing for progressively deeper segments of the fault. Using the proposed method for incorporating extension by subsidiary faults into the main extension by the master fault allows a close correspondence between calculated and observed fault position to be achieved. Strike-slip movement, transtensional deformation and basin inversion are common features in the Perth Basin. Basin inversion is characterised by extensive uplift and erosion, and by folding of the pre-breakup strata in major depocentres. The dextral strike-slip deformation in the latest Jurassic to Early Cretaceous, during final breakup of the Great India and Australia, resulted in a series of NW trending folds along major northerly striking faults. At the restraining bends of the major faults, contractional anticlines developed. Breakup of Great India and Australia also results in broad uplift and strong erosion. E-W transfer faults have been recognised only in the northernmost part of the onshore basin. They cut the major normal faults into segments of contrasting characteristics, limit the length of the extensional features, and transfer displacement among normal faults. There are also NW transfer zones which were active during breakup and control deformation of the sedimentary cover. Some of the northerly trending faults may swing at the NW transfers and some are restricted to one side of the transfer.s model is i.