K-Ar dated palynofloras in Tasmania 1: Early Oligocene, Proteacidites tuberculatus Zone sediments, Wilmot Dam, northwestern Tasmania

Abstract

Tertiaty lake sediments at Wilmot Dam, northwestern Tasmania, are dated as Lower Proteacidites tuberculatus Zone, based on the palynological zonation developed for the Gippsland Basin in eastern Bass Strait. The age limits of Early-Middle Oligocene for this zone are in excellent agreement with a K/Ar date of 26.7 Ma for basalts capping this deposit. Three new species are described: Tricolpites stylidioides, Mutisiapollis patersonii and Periporopollenites hexaporus. The first two appear to be the earliest records to date of Stylidiaceae and Mutisia (Asteraceae:tribe Mutisieae) respectively.