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University of South Florida

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Geophysics and Seismology

2003

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Exploring Links Between Physical And Probabilistic Models Of Volcanic Eruptions: The Soufriere Hills Volcano, Montserrat, Charles B. Connor, R. S. J. Sparks, R. M. Mason, Costanza Bonadonna, S. R. Young Jul 2003

Exploring Links Between Physical And Probabilistic Models Of Volcanic Eruptions: The Soufriere Hills Volcano, Montserrat, Charles B. Connor, R. S. J. Sparks, R. M. Mason, Costanza Bonadonna, S. R. Young

Geology Faculty Publications

Probabilistic methods play an increasingly important role in volcanic hazards forecasts. Here we show that a probability distribution characterized by competing processes provides an excellent statistical fit (>99% confidence) to repose intervals between 75 vulcanian explosions of Soufrière Hills Volcano, Montserrat in September–October, 1997. The excellent fit is explained by a physical model in which there are competing processes operating in the upper volcano conduit on different time scales: pressurization due to rheological stiffening and gas exsolution, and depressurization due to development of permeability and gas escape. Our experience with the Soufrière Hills Volcano eruption sequence suggests that volcanic …


Melting Processes And Fluid And Sediment Transport Rates Along The Alaska-Aleutian Arc From An Integrated U-Th-Ra-Be Isotope Study, Rhiannon George, Simon Turner, Chris Hawkesworth, Julie Morris, Chris Nye, Jeffrey G. Ryan, Shu-Hui Zheng May 2003

Melting Processes And Fluid And Sediment Transport Rates Along The Alaska-Aleutian Arc From An Integrated U-Th-Ra-Be Isotope Study, Rhiannon George, Simon Turner, Chris Hawkesworth, Julie Morris, Chris Nye, Jeffrey G. Ryan, Shu-Hui Zheng

Geology Faculty Publications

A comprehensive data set for young lavas erupted along the Alaska-Aleutian arc is used to examine how fluid and sediment transport rates and melting processes vary in response to systematic changes in subduction rate and dip along the arc and across the ocean-continent boundary. Positive correlations between convergence rate, volcano volume, and 238U excesses suggest that magmatic output is closely linked to the size of the fluid flux which occurred <10 kyr prior to eruption. Sediment-sensitive tracers like Th/Nb, Ce/Ce*, and 10Be/9Be also increase with convergence rate. However, the inferred 10Be/9Be ratio of this component is low relative to that in the incoming sediments, …