Carboniferous–Permian Event: Rise of the Glossopteris Flora on Gondwanaland

Vijaya

pp. 77-86, 1 plate, in English

Abstract:

The present paper is an analysis of the impact of Late Palaeozoic glacial stress on the evolving patterns in the morphology of spore-pollen, which were produced by the floras at the beginning of Mid-Carboniferous on Gondwanaland. The episodic occurrences of glaciation in Carboniferous–Early Permian had triggered the evolutionary shift in the cosmopolitan Lepidodendropsis flora of Early Carboniferous. This is an important event. Astray records of Glossopteris leaf in early Late Carboniferous NBG (Nothorachopteris, Botrychiopsis and Ginkophyllum) flora, and the occurrence of a disaccate pollen with fair number of radial monosaccate pollen, in the cingulated-zonate spores dominant assemblage is significant in the Southern hemisphere. The recently determined Zircon dates of Upper Carboniferous strata in eastern Australia gives a younger aspect to the Potonieisporites assemblage zone. With this datum, the Granulatisporites confluence oppel zone of the Grant Formation in Australia, younger to Potonieisporites Assemblage zone, may now be considered to span from Early Asselian to Sakmarian. The record of Stephanian on Gondwanaland thus becomes doubtful.

Keywords: Gondwanaland, flora, event