Lithostratigraphy of the upper Lower Devonian through the upper Middle Devonian succession of the southeast Darling Basin, western New South Wales, southeastern Australia: a case study of sedimentological features and significance of depositional facies

Detailed sedimentological analysis of depositional facies through lithostratigraphic correlation was conducted for the upper Lower Devonian through the upper Middle Devonian Snake Cave Interval strata of the southeast Darling Basin. The methodology used includes identifying changes in rock types from sedimentary lithotypes within different facies associations from well data, wireline-log patterns and palaeoenvironmental reconstruction. This has helped to define a lithostratigraphic correlation for the Snake Cave Interval section. This study has re-interpreted the upper and lower boundaries of the Snake Cave Interval using marked changes in gamma-ray log features and core and cutting lithology logs to estimate the depth of these boundaries from three wells. The Snake Cave Interval consists of ten lithotypes that define three facies associations (FAs) in the three available wells. These were deposited within three main facies associations: meandering fluvial facies association A (MFFA-A), braided fluvial facies association B (BFFA-B) and fluvio-shallow lacustrine complex facies association C (FSLCFA-C). The paper includes a broad description of the significance of lithostratigraphic facies related to depositional environments of the upper Lower Devonian through the upper middle Devonian succession section.