Age of Deccan Volcanism across KTB in Kxishna-Godavari Basin : New Evidences

摘要

The latest Paleontologlcal data suggest that the duration of Deccan trap eruption in Krishna-UoilaYari basin varies from place to place and could be anywhere between <0,5 Ma and 6 Ma across KTB. Three groups of fossils viz., Plankiic forarninii'era, Nannoplanktics and Dinoflagellate cysts suggest that the initiation of volcanism was during latest Maastrichtian within the upper part of Ahathomphalus mayai imnsis Zone, Micula murus Zone arid Tribiastula ulinensis Zone between 67 arid 66.5 Ma There are conflicting evidences in dating the upper age limit of the volcarucs probably due to diverse methods employed in calibration of foraniinifero' and narmoplanktic scales or selective retrieval of very small siied planUtics of zones PO and PI in well cuttings.