Dr. Leinen (URI) has been awarded funds to work with co-investigator Dr. Kyte (UCLA) to build upon earlier research funded by NSF. This previous work has demonstrated that non-fossiliferous pelagic clays may contain important but often overlooked geologic and paleoceanographic information. To date, the authors have conducted neutron activation analyses on 325 samples spanning 70 Ma of sediment in core LL4-GPC3 from the central N Pacific. They developed an inverse modeling technique that juggles the 39 elements analyzed in this core to match 8 end-member sediment components. From this is emerging a history of eolian, volcanic, hydrothermal, hydrogenous and biologic contribution to the Pacific ocean basin. With the present award, Drs. Kyte and Leinen will extend these analyses and modeling techniques to another long record (DSDP Site 576 in the western N Pacific) and will incorporate parallel mineralogic (XRD) analyses on surface sediments from throughout the N Pacific. The goal is to refine their understanding of the chemical and mineralogical controls on the distribution of major, minor + trace elements in N Pacific sediments, and continue to develop this technique as a new approach in paleoenvironmental interpretation.