Palynostratigraphic Zonations with Emphasis on Eco-Climatic Analysis to Resolve Major-Minor Environmental Changes in the Early Permian Sediments of Saharjuri Basin, Jharkhand
Subscribe/Renew Journal
Each of the palynostratigraphic zone represents a characteristic ecological phase of deposition. The palynostratigraphic zones have been identified on the basis of the stratigraphically restricted occul-rence of quantitatively dominant and qualitatively significant taxa in the palynoassemblages. Altogether fifteen such zones are recognised viz., Ecol. Ph. PNSJ T and I-XIV. These fifteen Eco- palynostratigraphic zones were deposited under the influence of major climatic phases viz. cool climatic phase (C1. Ph. I), temperate climatic phase (C1. Ph. II) and warm climatic phase (C1. Ph. III). The temperate climatic phase C1. Ph. II is the most prolonged phase of deposition in the Saharjuri basin; this phase however has record of three minor but distinct sub-phases of climatic fluctuations. The sub-phases are stratigraphically restricted and represent characteristic palynoassemblages. One of the ecological phases viz., Ecol. Ph, PNSJ XII is distinct from the other ecoassemblages in the qualitative and quantitative abundance of taxa of brackish to marine environment. This minor phase of deposition is identified as Marine Transgression in the essentially continental facies of deposition. The stratigraphic horizons with characteristic assemblage of clearly distinguishable minor Eco-Climatic zones are identified as 'Marker Horizons'.
The major and minor climatic phases, sub-phases, ecological phases of Marine Transgression, identified as the Marker Horizons in the Saharjuri basin closely correspond with the similar sequential changes of climatic and ecological phases of Marker Horizons in the adjoining Rajmahal basin and other basins of India and Early Permian of Bhutan in the eastern Indian subcontinent.
Keywords
Abstract Views: 176
PDF Views: 2