Late Cretaceous diurnal tidal system: A study from Nimar Sandstone, Bagh Group, Narmada Valley, Central India

Abstract

Tidalites from the Cenomanian Nimar Sandstone, Bagh Group, Central India, are represented by (i) laterally accreted tidal bundles, (ii) herringbone cross-strata, (iii) sigmoidal cross-strata and (iv) tidal rhythmites with lenticular/wavy bedding. These indicate sedimentation in an upper subtidal to lower intertidal setting within fluvio marine interactive system. Time-series analysis of continuous rhythmic foreset bundles (sub-annual scale) manifests neap-spring tidal cycles within a diurnal tidal system with synodic and sidereal month lengths of ~28.4 lunar days and ~26.28 solar days respectively. Estimated Earth-Moon system parameters of the Late Cretaceous reveal no significant changes during the last ~100 Ma.