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Cauvery Basin is a pericratonic rift basin formed during Late Jurassic to early Cretaceous. This basin gained importance, as it comprises the Albian-Maastrichtian outcrop sediments with good fossil record. This synrift sequences have high hydrocarbon potential with a good source rock development in the basin. A re-look of Cretaceous stratigraphy of southern India with an integrated concepts attempted and proposed the sequence stratigraphic classification. This classification is based on the vertico-lateral relationship of rock record, high resolution biostratgraphy, petrography, and events signatures. The four mega sequences of 2nd/3rd order sequences were recognized, viz; Dalmiapuram, Garudamangalam, Sillakudi and Kallankurchchi sequences. The oldest sedimentary unit overlying the Archaean basement is the Terani plant beds is bounded below by sequence boundary-1(SB-1).The surface separating Terani plant beds and the overlying coral algal limestone of Dalmiapuram Formation is the SB-2. The upper surface of Karai shale unit was exposed due to basin uplift possibly caused by the rise of Marion igneous intrusion, represents the SB-3 of Dalmiapuram sequence. The Garudamangalam sequence is bounded below by SB-3 and above by SB-4. In the Campanian section(Sillakkudi Formation), the Kaller conglomerate bed marks the SB-4, formed due to RSL fall at the end of Sillakkudi sequence. Overlying the Kaller conglomerate is the Kallankurchchi Formation, represents four parasequences. The base of ferruginous limestone is a transgressive surface indicating first marine flooding within the Kallankurchchi Formation. The TST consists of three deepening upward parasequences of ferruginous limestone, lower arenaceous limestone and Gryphaea limestone. The stacking patterns of these retrogradational parasequences correspond to intermittent flooding events. Both mega,and microfossil assemblages, the frequencies and preservation of microfossil tests, indicates a gradual upward increase in paleobathymetry. The Gryphaea limestone unit represents the best developed MFS in the area.Abundant giant-sized Gryphaea suggests a tranquil environment, observed during high stand sea-levels. The upper Arenaceous limestone unit with high silica content and reduced faunal frequency forms the HST. Paleobathymetry trend as inferred from Dalmiapuram Formation compares with the global and regional sea-level curves. The fall in relative sea-level that accompanies the coral algal limestone of Dalmiapuram Formation is affirmation with the eustatic sea-level curves of Haq (1987) and relative sea-level curves of Ramanathan (1977). Rise in relative sea-level during Karai Formation agrees well with Haq and Ramanathan. The occurrence of Garudamangalam Formation indicates abrupt shallowing of the basin overlain by sandstone facies. The distinct unconformity surfaces marked by Kaller conglomerate at the upper boundary of Campanian corroborate with relative fall in the global sea-level curve.
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