Palaeoecological, Palaeoenvironmental and Age Implications of the Cretaceous-Palaeogene Microbiota-Bearing Deccan Intertrappean beds of the Chhindwara District, Madhya Pradesh, India

Abstract

The charophytes recovered from the intertrappean beds of Jhilmili and Ghat Parasia point to a shallow, alkaline, freshwater/lacustrine environment over a shallow marine environment during low tide intervals in Jhilmili and a freshwater environment in Ghat Parasia. The ostracod assemblage recovered from the four localities, namely, Jhilmili, Ghat Parasia, Shriwas (=Shiraj) well and Government well of the Chhindwara District, Madhya Pradesh, includes both passive swimmers (Darwinula, Frambocythere Gomphocythere and Limnocythere) and active swimmers (Cypridopsis, Mongolianella, Paracypretta and Zonocypris). The vast majority of the ostracod fauna suggests a freshwater, lacustrine low-energy depositional environment. The presence of two brackish water ostracod species (Buntonia whittakerensis sp. nov. and Neocyprideis raoi) and planktic foraminiferans fuels speculation about a marine seaway in central India from Maastrichtian-Early Palaeocene along the Narmada and Tapti rift zones by seasonal offshore currents (short lived transgressive phase). Deposition at Jhilmili locality in central India took place in mainly terrestrial semi-humid to dry environments, followed by a brief aquatic interval (60 ka) of fresh water lakes, which resulted in low coastal marine and estuarine conditions with early Danian Pla planktic foraminiferans and brackish water ostracods. The presence of fish remains containing myliobats, osteoglossids and lepisosteids has led to the conclusion that a freshwater environment prevailed during the deposition of fish-bearing units of the Ghat Parasia, Shriwas (= Shiraj) well and Government well, and Jhilmili intertrappean beds. Furthermore, their occurrences show the occurrence of a near-shore or coastal-plain environment.