Partition Studies in the Sediments of Deep Sea Drilling Project Site 220 in the Southeastern Arabian Sea

Abstract

Partition patterns of Al, Fe, Mn, Ni, Co and Cu have been studied in sediments. These studies have revealed that all the elements have both acid insoluble and non-lithogenous components in these sediments and exhibit differences in their distribution pattern in the sedimentary column. While the concentrations of different elements associated with the acid insoluble fractions are fixed in sediments in a solid state and the differences found can be attributed to differences in the nature of the material the site received during different periods, the concentrations associated with the non-lithogenous component of sediments appear to have been fixed in a number of ways. While Al, Fe and Mn seem to be associated with the clays and carbonate phase, Ni, Co and Cu in sediments appear to have been fixed through adsorption on clays and organic matter and by ferric and manganese hydroxides. Considering the depositional history of the site, rates of sedimentation during different geological periods and the nature of the material deposited, it is tentatively suggested that the differences found in the concentrations of different elements in the nonlithogenous fraction are related to a large extent to differences in rates of sedimentation and to the character of the material in the different lithological units.