LITHOGENIC FLUXES IN THE BAY-OF-BENGAL MEASURED BY SEDIMENT TRAPS

Lithogenic flu measured continuously for 1 year using time-series sedi ment traps at two sites in the Bay of Bengal show a strong seasonality with 43-49% of the duxes to the deep traps occurring during the SW mo nsoon. Lithogenic fluxes increased with depth and the rate of increase was maximum during periods of high freshwater influx. Simultaneous se dimentation of lithogenic and organic matter is seen at both the sites . Clay mineral studies show that illite percentage decrease and smecti te percentage increase with depth. Due to the prevailing circulation p attern, iIlite-rich suspended sediments from the Ganges-Brahmaputra Ri vers are transported southwards in the surface low salinity layer whil e smectite-rich muds from the continental margins are resuspended and transported at depth in perhaps somewhat heavier clock-wise circulatio n. (C) 1997 Elsevier Science Ltd.