Trace fossil assemblage of Oligocene (Barail Group) from Zote Area, Champhai District, Mizoram

Abstract

The Barail Group (Oligocene) of Zote section, Champhai district, Mizoram has been studied, for the first time, on the basis of trace fossil. The study areas consist of different rocks like Sandstone, siltstone, shale and their admixture in various proportion. The present paper documents 14 ichnofossils such as Arenicolites isp., Gyrolithes lorcaensis, Helminthopsis abeli, H. hieroglyphica, H. tenuis, Laevicyclus mongraensis, Lanicodichna medulata, Palaeophycus sulcatus, P. heberti, Psilonichnus tubiformis, Skolithos linearis, S. verticalis, Teichichnus spiralis and Thalasinoides paradoxicus. The different ichnoassemblages present in Zote area correspond to the Psilonichnus, Skolithos and Cruziana facies. With the analysis of Ichnofacies and lithofacies, studied rock of Barail Group exposed in Zote area is interpreted as to have been deposited under fluctuating energy condition, sandy substrate to sublittoral zone of shallow marine environment.