Late Cretaceous-Tertiary Sediments and Associated Faults in Southern Meghalaya Plateau of India Vis-a-Vis South Tibet: Their Interrelationships and Regional Implications

Late Cretaceous-Tertiary sediments together with the underlying Sylhet Trap and Precambrian granites/gneisses are exposed along the southern fringe of Meghalaya plateau. This huge pile of sediments is dissected by E-W and NNE-SSW striking faults. Several workers postulated a direct correlation between tectonism and sedimentation, interpreting the E-W striking Dauki fault as a 'growth fault'. The present work suggests that the sedimentation of this pile is controlled by basin transgression and regression and not by the Dauki or other faults. Dauki fjult being post-Kopili (post-Eocene) in age, could not have acted as a growth fault during the deposition of these Late Cretaceous-Palaeogene sediments.

In the plate tectonic version of Greater India in Gondwanaland, a broadly coeval lithofacies and biofacies assemblages existed in Late Cretaceous-Palaeogene sequences of the southern Tibetan plateau and southern Meghalaya plateau. While the sedimentation in Tibet during Palacogene is dominated by carbonate rocks - except at the KIT boundary (Jidula Formation), the sedimentation in southern Meghalaya is represented by arenaceous and calcareous rocks.