Late Quaternary Evolution of the Shelf Environment off North Kerala: Faunal and Sedimentological Evidence

Four gravity cores from the shelf off the southwest coast of India were studied in detail for various microfaunal and sedimentological parameters The study enabled to establish chronostratigraphic subdivisisons in two late Quaternary outershelf sediment cores using stable oxygen isotopes foraminifera and pteropod records and Iithological characteristics combined with the radiocarbon dates The Innershelf cores display two distinct benthic foraminiferal biofacies and corresponding hthofacies representing the late Pleistocene and the Holocene periods The investigation indicates that the planktic forarninifera/ benthic foraminifera ratio, pteropods/planktic foraminifera ratio, absolute abundance, species diversity and epifaunal/infaunal ratio In benthic foraminifera1 population can be potential criteria for biostratigraphic subdivisions in shelf sedimentary records which are mainly expressions of past changes in sea level and environmental condlt~onsD own-core vanatlon in benthic foramin~ferarle cordsreflects changes In bathymetry and environmental conditions associated with sea level variation and glacial interglacial boundary conditions in the last 23 kyr Foraminiferal and sedimentological records further indicate a probable existence of paleoestuary In the study area.