THE LOWER BOUNDARY OF THE TRIASSIC AND ITS CORRELATION IN MARINE SEDIMENTS: PAPER 1. BOUNDARY SECTIONS OF THE TETHYS

Abstract

In the Tethys region, the Triassic starts with the ammonite Otoceras woodwardi Zone accepted as basal in this system more than a hundred years ago. The boundary layers in Ciscaucasia, Iran, western Pakistan, Kashmir, central Himalayas, southern China, and Thailand are considered. The uppermost Permian deposits bearing Paratirolites or Pseudotirolites are well represented in the Paleotethys sections. In the Neotethys sections, the Otoceras genus often appears along with the Ophiceras genus and in association with conodonts Hindeodus parvis.