Publication Name: The Sedimentary Basins of WA
Authors: V.R. Labutis
Publication Volume: 1
Date Published: July 1994
Number of Pages: 33
Reference Type: Book Section
Abstract:
An abundance of papers based on various approaches to sequence stratigraphy has appeared in the international and Australian literature in recent years. That not all have shown a thorough understanding ofthe basic concepts is understandable, given the confusing array of models and terminology.
Biostratigraphy is one of the criteria for identifying and correlating sequence boundaries but is fraught with difficulties in regional and global ties between different zonations and time scales. Condensed sections do not
necessarily indicate basinal or deep water environments and those penetrated in wells are generally from nearshore environments. Also sequence stratigraphy recognises many more unconformities than have been
previously identified, intensifying problems related to accurate age dating and extensive reworking of fossil
assemblages at sequence boundaries.
A sequence stratigraphic framework is presented for the North West Shelf based on the Australian zonation of Helby et al. (1987), EXXON models of sequence stratigraphy and the time scale of Harland (1982). Previous work has emphasised deep water environments for the Jurassic-Cretaceous and the shelf-break basin model in sequence stratigraphic studies. However, the ramp basin models are more appropriate for the twinrift development of the North West Shelf basins without a shelf break. The sequence stratigraphic analysis provides insight into the timing, rifting history and type of tectonic deformation affecting the North West Shelf.