Publication Name: The Sedimentary Basins of WA
Authors: M.C. Dentith, A. Long, J. Scott, L.B. Harris and S.A. Wilde
Publication Volume: 1
Date Published: July 1994
Number of Pages: 20
Reference Type: Book Section
Abstract:
Tectonostratigraphic (suspect) terranes have beenrecognised within both the Archaean Yilgarn Craton, to the east of the Perth Basin, and in the Pinjarra Orogen which the basin overlies. However, there is evidence that only one of these Archaean boundaries played a significant role in the evolution of the basin. The intersection of the boundary between the Boddington and Lake Grace terranes with the eastern margin ofthe Perth Basin coincides with a change in trend of the margin, the development of the Urella Fault as the main basinbounding structure and also the location of the Abrolhos fault (accommodation) zone. These is also evidence that the location of the Harvey Ridge, an accommodation structure which separates the Bun bury and Dandaragon troughs, was controlled by reactivated Archaean structures.Proterozoic suspect terranes which form the basement to the Perth Basin contain structures of different type
and orientation. Where basement is at relatively shallow depth, for instance near Northampton, there is a clear
correlation between fault trends in the basin and the basement. Where basement is at greater depth reactivated structures seem to have less influence and analogue modelling suggests that contrasts in basement
rheology may be of greater significance. Different authors have proposed contrasting tectonic histories for the Perth Basin based on studies of fault orientations in particular areas of the basin. Failure to account for the effects of differences in basement across the basin may be the explanation for this lack of consensus.