CSEDI Collaborative Geochemical Research on the Deep Mantle

Walker, David

EAR-0001963

This is a collaborative (University of Maryland and Lamont-Doherty Earth Observatory), multidisciplinary project designed to further test the possibility of core-mantle interaction. It will utilize a combination of isotope geochemistry and experimental petrology/geophysics. Specific objectives are to: 1) Precisely measure the 186Os-187Os systematics of two carefully chosen plume-derived systems, and assess if there is a positive relation between 186Os and 187Os enrichment. 2) Begin a search for isotopic anomalies in the short lived 107Pd-107Ag, 182Hf-182W, 98Tc-98Ru and 97Tc-97Mo systems in the plume derived rocks for which the 186Os-187Os evidence suggests the presence of a core component. 3) Begin experimental work to examine the metal-silicate partitioning behaviors of Pt, Re, Os, Hf, W, Pd, Ag, Mo, Tc and Ru between silicate and metal at high pressures. The goal of this research is to generate a substrate of data on which to make predictive models of the behaviors of the isotope systems composed of these elements resulting from core segregation in both metal and silicate reservoirs. 4) Measure FeO solubility in liquid Fe alloy at high pressure to evaluate the potential for recovery of core geochemical signals by transferring material from the core to the mantle by exsolution.