Palaeocene-Eocene Boundary in Cauvery Basin

The authors favour the placement of Palaeocene-Eocene boundary at the Pseudohastigerina wilcoxensis datum. In the Cauvery basin subsurface, seemingly continuous late Palaeocene-Early Eocene successions are known only in the basinal depressions, which have been exemplified by the Chidambaram well data. Unless the sequences are well represented by cores, problems arise in delineation of Palaeocene-Eocene boundary in the flanks of ridges/highs in Cauvery basin as the index Palaeocene planktonic foraminifera are sometimes found reworked in the Eocene zones.

The occurrence of Nummulites, whose earliest occurrence is lately being attributed to the basal Eocene in the European basins, in the Cauvery basin Palaeocene corresponding to the Globorotalia velascoensis and Globorotalia pseudomenardii Zones - has been stressed. Further research is necessary in order to establish the evolutionary appearance level of these camerinids in the Indian subcontinent.