Campanian - Maastrichtian Nannoplankton biostratigraphy of the Narsapur claystone Formation, Krishna-Godavari Basin, India

Nannoplankton biostratigraphy of the Campanian - Maastrichtian 870 metre thick argillaceous subsurface sediments below the Lowest trap of Narsapur area, Krishna-Godavari Basin has been presented in the paper. These infratrappean sediments are assigned to Micula nurus and Arkhangelskiella cymbifomis zones of Late Maasbichtian age and undifferentiated CC 19-CC 23 nannoplankton zones of the Campanian age. Occurrence of global Late Maastrichtian marker Micula murus just below the lowest trap is significant and considered to be important short lived nanno-event in Late Maastrichtian times. The initiation of oldest volcanic eruption in the Narsapur area is around 67.0 Ma. (middle of Micula mums zone) and it is correlated with the lowest limit of the Deccan volcanism in Razole area.