Inter-Conections between Narmada and Cauvery basins during Turonian (Late Cretaceous) Time

During the Late Cretaceous times the Narmada Basin in the Central India and Cauvery Basin in South India received a thick pile of marine sediments as a result of the global Cenomanian marine Transgression. It is believed that Tethyan sea became narrower facilitating the formation of Indian ocean as a result the large part of the Indian Plate especially Kachchh, Narmada and Cauvery basin inundated. The Late Cretaceous sediments of Narmada Basin is popularly known as Bagh Beds which ranges in age from Cenomanian to Coniacian. In the Cauvery Basin Late Cretaceous sediments are known as Trichinopoly Beds and range in age from Middle Aptian to Maastrichtian. The Turonian sediments of Narmada Basin is grouped as Nodular Limestone Formation and in Trichinopoly region Maruvattar and Paravay formations. Both of these have more or less similar history, although affected by fluctuating sea levels, rate of local subsidence and rate of sedimentation resulting in different lithological framework. An attempt has been made to use Turonian bivalves of the two sub-basin to give further ascertain of the views of the faunal synochronisation in these parts of Narmada and Cauvery basins. The common bivalve divides in both these regions during Turonian those are Modilous (Modilus) typicus, Acesta obliquistriata, Plicatula numidica, Pinna laticostata, Plicatula batnensis, Astarte similis, Opis concentricus, Cardium (Protocardia) hillanum, Mytiloides labiatus, Protocardia pondicherriensis, Pycnodonte(phygraea) vesicularis, Lopha(Actinostreon) diluviana, Agerostrea ungulate etc. This may imply that an eastern area of sea could have inundated the lower Narmada Basin and further extended up to Cauvery Basin during Turonian time.