Collaborative Research: Chemical Geodynamics of the Galapagos Mantle Plume-Spreading Center System

San Diego State University Foundation, San Diego CA

Investigators

Abstract

This is a collaborative study with German scientists from GEOMAR, as part of the MEGAPRINT expedition that took place aboard the R/V Sonne during 2001. The field program sampled critical, unmapped sections of the eastern Galapagos Spreading Center (GSC) and portions of young seafloor between the archipelago and the spreading center. Elements of the program included multi-beam seafloor mapping, shipboard gravity and magnetic surveys, and sampling of lavas by dredging at ~15 km spacing along the eastern GSC, and at numerous off-axis seamounts and volcanic ridges. Guided by ~100 major element glass analyses already completed, the PIs propose an analytical program that will determine trace element contents, He, Pb, Nd, Sr and Hf isotope compositions, volatile (CO2 ,H2O, Cl, F and S) contents and 40Ar-39Ar radiometric ages of a representative suite of these submarine glasses and rocks. Geophysical data from German colleagues will provide additional constraints on age, structure, thickness and tectonics of the crust and lithosphere.