Publication Name: The Sedimentary Basins of WA
Authors: Brian W. Logan, David J. Frances and Maritsa Economo
Publication Volume: 1
Date Published: July 1994
Number of Pages: 35
Reference Type: Book Section
Abstract:
The paper is an account of the nature and genesis of a carbonate dilaform that is embedded in Devonian formations that crop out on Brooking Springs station in the northern Canning Basin. It is a kilometre-scale,composite structure composed of a 30 km-long vertical wall and a sub-horizontal, 20 m thick, tongue-like
apophysis. The dilaform is an example of a range of congeneric structures that occur in the Canning and other sedimentary basins and that are of considerable exploration significance.
The term 'dilaform' is used to denote-carbonate masses that occur in basinal sections and which are ecognisable
as having grown therein during the burial phase or ensuing tectonic events. Dilaform growth reflects the volume increases (inflation) and mass gains that are consequences of dilation of the host (precursor) formation by pressurised fluids.
Cavity-cast networks composed of materials that were introduced at the time of inflationary growth make up the greater part of the structure along with subordinate quantities of precursor limestone. The cavity-fillings include various carbonate precipitates and also materials that were injected as pressurised slurries.