The Hawkesbury Sandstone dominates the Sydney region, both from the viewpoint of engineering structures and the natural topography. This Formation thickens from its western and southern outcrop margins in the Blue Mountains and Illawarra to about 290 m near the Hawkesbury River.
This article is an expansion of one published in 1985 in the volume “Engineering Geology of the Sydney Region”. The original document concentrated on the engineering properties of the intact sandstone (i.e. the ‘substance’) whereas this article covers both substance and rock mass parameters. Much of the original information on substance parameters is reproduced here with additions from papers published in the volume “Sandstone City” published in 2000 by the Geological Society of Australia. The rock mass data are taken from papers published since 1985.