9730743 Basu This grant provides three years of partial salary support for a Technical Associate in the mass spectrometry laboratories of the Department of Earth and Environmental Sciences at the University of Rochester. The isotope geochemistry Technical Associate will provide support for both the thermal ionization and plasma source mass spectrometer laboratories under the directions of Dr. Asish Basu and Dr. Ariel Anbar, respectively. The combined mass spectrometer laboratories at Rochester offer unique analytical capabilities for a variety of trace element and isotope ratio measurements that will augment the research of faculty and students in earth processes and evolution. The support for the technical position will allow collaborative work among Rochester faculty and with outside investigators, and will promote in-house analytical research involving trace element and isotope geochemistry. ***