This work proposes to undertake a systematic study of the hydrogen and oxygen isotopic composition of the waters of the Black Sea. These data will establish the origin of the various water units, their mixing patterns and rates. As there are several sources of freshwater input in the Black Sea, simple salinity measurements cannot reveal this information. These data in conjunction with noble gas, 14C, tritium and other radioactive tracer work proposed for the forthcoming Black Sea cruises will enable a more clear understanding of the circulation mechanisms and patterns of the Black Sea. A secondary objective of this proposal is to determine what influence, if any, the decomposition of organic material and hydrocarbons have upon the &D of the water.
