Morphology, geochemistry, and evolution of Serocki volcano

Abstract

Basalts collected during drilling and diving programs on Serocki Volcano mostly fall within a limited compositional range, and are moderately evolved, normal MORBs with distinctive high MgO contents and high Al2O3 concentrations. However, samples recovered from within the central crater have lower TiO2 and FeO*/MgO, and higher MgO and Al2O3 concentrations. Comparison of the observed geochemical variations with low-pressure experimental work and other samples from the region suggests that the Serocki Volcano and Site 649 data are compatible with crystal-liquid fractionation involving both olivine and early-stage clinopyroxene, as well as plagioclase, and that the sources may be similar even though Sites 648 and 649 are located in different, but adjacent, spreading cells. Consideration of the stratigraphy and morphology of Serocki Volcano suggests that this feature is more properly described as a metatumulus or lava delta, associated with a steeper, conical peak to the southwest. -from Authors