ABSTRACT: Cretaceous sequences of the Cauvery Basin, South India, can serve as an analogue to understand the subsurface successions with proven potential for commercial hydrocarbon exploration. In this area, the distribution of hydrocarbon reservoir and source rock facies was profoundly influenced by relative sea level changes amplified by rifting and related tectonic activities. Of particular interest are the sedimentary strata exposed in mines, quarries and outcrops around the Ariyalur area of Tamil Nadu, that mirror subsurface strata. This study reviews and integrates the stratigraphic studies based on this area and published over the past three decades. In particular, we concentrate on lithological features, macrofossils, microfossils, ichnofossils, magnetic polarity and sequence stratigraphy to reveal the geologic history of the Cauvery Basin. Age control, paleoenvironmental interpretations, paleobathymetry, paleoecology and paleotemperature are based on ammonites, belemnites, brachiopods, mollusks, nannofossils, and foraminifera. Key results include an integrated stratigraphic framework, paleobathymetry and sea level history that shows seven second/third-order depositional sequences, and major sea level falls during the late Turonian and late Maastrichtian linked to the Marion and Reunion mantle plumes, respectively.

Files