This is a continuation of an integrated, multi-disciplinary project combining seismic, petrologic, geochemical, and numerical modeling. The project focuses on the Galapagos spreading center between 91 and 98 degrees west. The initial work provided the first complete multibeam bathymetry of the axial region, quantified variations in crustal thickness, determined the distribution of seismic reflectors from the top of crustal magma reservoirs, defined along-axis variations in geochemistry, and modeled these variations in terms of mantle source enrichment and extent of partial melting. The objectives of the continuation are to refine models of the relationship between axial thermal structure and axial morphology, combine seismic and petrologic observations to constrain variations in magma reservoir properties, and integrate seismic constraints with new measurement of U-series disequilibria to constrain variations in mantle upwelling rate, temperature and source composition.
