This is a collaborative project between Alfred Anderson of the University of Chicago and Dork Sahagian of Ohio State.The main goal of the project is to establish whether gas accumulates beneath Kilauea's summit. The idea is that gas accumulation at the structural apex can cause persistent localization of a summit vent. Additional goals are: 1) to use melt inclusions to establish the depths of olivine crystallization beneath Kilauea: and 2) to confirm the initial bulk concentration of C02 and H20 in Kilauean parent magma. Subaerial and submarine Kilauean basalts will be studied. Inclusions of glass in Olivine phenocrysts will be analyzed for major elements and S by electron microprobe and for H20 and C02 by infra-red spectroscopy. In addition the size, abundance and gas pressure of vesicles in glassy submarine basalts will be measured. The sizes and gas pressures of gas bubbles in glass inclusions will be measured for comparison with the vesicles in host glasses. Calculations will be performed to assess the coalescence and rate of rise of bubbles in the evolving body of magma beneath Kilauea. The results will be compared with existing data on the historical rates of outgassing, magma influx, and eruption. The data and computations will be used to test and refine existing models of the outgassing and evolution of Kilauea volcano. Overall, the PIs will test the idea that Kilauea is a centralized volcano because rising gas seeks and maintain a vent at its summit.
