Late Eocene-Early Oligocene Biostratigraphy of Mansa-Indrora Area, Cambay Basin

Late Eocene-Early Oligocene succession from two well sections of north-eastern margin of Cambay Basin was analysed for their foraminifera1 content. It has yielded rich larger foraminifera a few planktonic and benthonic foraminifera. Three larger foraminiferal biozones have been recognised for the succession in geologically ascending order. These are Nummulites fabianii Partial Range Zone (? 39.4 m.y. to 37.4 m,y., i.e., ? P 15 to 16); Discocyclina dispansa - Nummulites fabianii Concurrent Range Zone (37.4 m.y. to 36 m.y.. i.e., Zone P 17) and Nummulites fichteli Partial Range Zone (36 m.y. to? 35 m.y., i.e., Zone P18), The environment of deposition has varied from shallow marine to inner and outer shelf conditions in the course of the development of the succession.