Abstract : We interpret the subsurface distribution pattern of Late Cretaceous sandstone reservoirs in the Ramnad sub-basin within the framework of sequence stratigraphy via biostratigraphic and lithostratigraphic correlation with outcrop sections in the Ariyalur area of the Cauvery basin. The sequence stratigraphic surfaces recognized in outcrop sections can be correlated to subsurface sections by using biostratigraphic datum markers. By this method five 2 nd and 3 rd order sequences can be recognized in outcrops of the Ariyalur area based on sequence boundaries (SB): 1) the top of the Terani Formation (latest Aptian-earliest Albian SB1), 2) the Karai Formation (middle Turonian Marginotruncana sigali Zone SB2), 3) the Anaipadi member of Garudamangalam Formation (late Santonian Dicarinella asymetrica Zone SB3), 4) the Sillakudi Formation (late Campanian Globotruncanita calcarata Zone SB4), 5) the Ottakovil Formation (early late Maastrichtian Gansserina gansseri Zone SB5), and 6) the Kallamedu Formation (late Maastrichtian Abathomphalus mayaroensis Zone SB6). Examination of log profiles of the Koluvur, Ramnad, Perungulam, Chumaitangi, Kanjirangudi, Periapattinam, Ramanavalasai and Uchipuli structures show that sea level lowstands at the end of the middle Turonian, late Santonian and late Maastrichtian are associated with coarser clastic sediments in deeper parts of the basin. This suggests that low sea levels are associated with bypass of coarser clastics in shelf areas and deposition as fan deposits in the deeper parts of the basin. Major sea level falls thus significantly influence the distribution of coarser clastic sediments and the application of sequence stratigraphic concepts aids the understanding of sandstone reservoirs in the Ramnad sub-basin.