Silicified wood of Early MioceneNothofagus, Acaciaand Myrtaceae (aff.EucalyptusB) from the upper Lachlan valley, New South Wales

Abstract

Three specimens of silicified wood, two transported and one probably in situ, have been found in association with Early Miocene basaltic lavas in the upper Lachlan valley, N.S.W. On the basis of their preserved structure, the three specimens have been identified as belonging to Nothofagus, Acacia, and the family Myrtaceae, respectively. The specimen of Nothofagus (one of the transported specimens) constitutes the first identification of a macrofossil of this genus from this interval in southeastern mainland Australia, while its conjunction with the myrtaceous specimens (one probably in situ) may indicate vegetation zonation according to elevation, as proposed on pollen evidence from Kiandra. Such zonation is not demanded by the upper Lachlan evidence, however, but if it is favoured, reconstruction of the Early Miocene geography of the upper Lachlan constrains the maximum elevation above the locality of the myrtaceous fossils to be 350 m.