Siluro-Devonian strata east of Wyalong.

Abstract

Siluro-Devonian fossils in rocks east of Wyalong indicate the presence of Derriwong/ Trundle Beds equivalents in this region.

The terminology dealing with glaciogenic and similar nonglaciogenic sedimentary rocks is briefly reviewed. The term tillite is used as a comprehensive genetic term for both continentally deposited and ice-rafted indurated tills. The term mixtite is used for sedimentary rocks that resemble tillites but are of uncertain or unknown origin. The appropriateness of the term tillite in formal lithostratigraphic nomenclature is discussed.

Two broad physiographic subdivisions may be recognized on that part of the New South Wales continental shelf covered by the Narooma 1:100,000 sheet. The inner, gently sloping region may be designated the shoreline zone and the outer, flat region, the shelf plain. Three lithofacies may be recognized within the unconsolidated shelf sediments.