9616241 McManus Trace element distributions in seawater and in the sediment record are often used as proxies for both modern and paleooceanographic conditions or processes. However, before their full potential can be realized, the behavior of these elements after deposition and shallow burial on the seafloor must be clarified. In this study, researchers at Oregon State University and the University of Southern California will study the geochemistry of two potential paleoindicator elements, barium and germanium, in the hard parts of planktonic marine organisms deposited in sediments collected from several oceanic regions. Specifically they will evaluate the common assumptions that Ge is not fractionated from deposited siliceous frustules and that the Ba: Alkalinity relation in seawater is related to a coupled stoichiometry between organic carbon decomposition, dissolution of barium, and dissolution of calcium carbonate. The results are expected to better define the advantages and limitations of these elements as tools for paleooceanographic reconstructions.
