Facies architecture of a last interglacial barrier: a model for Quaternarybarrier development from the Coorong to Mount Gambier Coastal Plain, southeastern Australia

The last interglacial Woakwine Range, a Linear, barrier shoreline complex o f temperate bioclastic carbonate origin, in the southeast of South Australi a, occurs essentially uninterrupted over a distance of 300 km and up to 10 km inland from the present coastline. Mapping of the internal facies archit ecture of the barrier as revealed in McCourt's Cutting southeast of Robe, r eveals the presence of transgressive and regressive facies associated with the last interglacial maximum (Oxygen Isotope Substage 5e), as well as an o lder aeolianite within the core of the barrier, con-elated herein with Oxyg en Isotope Stage 7. Amino acid racemisation and thermoluminescence dating i ndicate that volumetrically, the majority of the Woakwine Range is of last interglacial age. The bulk of the barrier structure comprises aeolian facie s in the form of landward-migrating coastal dunes. The internal facies appe ar to record the culmination of the post-Stage 6 marine transgression at th e onset of Substage 5e, and possibly the termination of Substage 5e based o n the shallow seaward dip of the discontinuity between regressive littoral and sublittoral facies. (C) 1999 Elsevier Science B.V. All rights reserved.