A TIDAL ISLAND MODEL FOR CARBONATE SEDIMENTATION - KARONDIA LIMESTONEOF CRETACEOUS NARMADA BASIN, INDIA

The Cretaceous sedimentary sequence of Narmada basin comprise a lower elastic formation (Nimar Sandstone) and an upper carbonate sequence (K arondia Limestone). The depositional model of limestones was reconstru cted by identifying 8 microfacies which were regrouped into 5 facies a ssociations. The carbonate sequence of the study area was interpreted to be deposited on a ramp without a striking break in the slope of the ramp and where shelf margin was not developed. The vertical arrangeme nt of facies of Karondia Limestone forms a shallowing upward sequence. It shows much lateral and vertical variation which can be attributed to deposition on a platform dotted by a mosaic of exposed banks or isl and separated by subtidal areas with the whole complex shifting both l aterally and vertically in response to hydrodynamic conditions through time.