Sr, Nd, Pb and Hf isotopes of basalts from the Quebrada/Discovery/Gofar transform fault system;key to test models of melt generation,transport and focusing beneath mid-ocean ridges

Brown University, Providence RI

Investigators

Abstract

Mid-ocean ridges are associated with the largest number of active volcanoes and volcanic features on Earth. Understanding how magmas erupting on the seafloor form and from what depths and parent compositions/lithologies they are sourced, is critical for being able to predict and model complex crustal processes. This research will complete the geochemical characterization of an important suite of lavas collected from the East Pacific Rise in the Central Pacific Ocean by producing the Sr, Nd, Pb, and Hf isotopic compositions of over eighty lavas from the Quebrada/Discovery/Gofar transform fault system. The isotope data will complement already existing major and trace element chemical suites and measurements of volatiles trapped in the volcanic glasses. By combining these new geochemical data with computer models of geodynamic processes, this research will allow the composition of mantle source material to be determined, as well as the physical condition under which melts are generated, transported, and aggregated under mid-ocean ridges. Broader impacts of this research are multifaceted and strong. They include tight integration of research and education, with undergraduates being involved in the full research process and being trained in state-of-the-art geochemical analytical work. Working with university programs that recruit minority scholars, the investigator will include minority students in his research group and train them in research thinking and high-end analytical work over the summer. Through the lead investigator and students involved in his laboratory, there will also be significant interaction with local elementary schools to help provide them with science programs and scientist role models to replace science educators who, due to budgetary constraints, have been cut from elementary school programs. Other broader impacts include support of an institution in an EPSCoR state (Rhode Island) and support of an NSF-funded analytical instrument which serves institutions across the state of Rhode Island.