HR: 16:00h
AN: V24B-01    [Abstracts]
TI: Rapid Syn-eruptive Ground Deformation During July 2003 Soufriere Hills Volcano Eruption Constrained by Continuous Kinematic GPS
AU: * Styron, R H
EM: rstyron@uark.edu
AF: Department of Geosciences, University of Arkansas, 113 Ozark Hall, Fayetteville, AR 72701, United States
AU: Mattioli, G S
EM: mattioli@uark.edu
AF: Department of Geosciences, University of Arkansas, 113 Ozark Hall, Fayetteville, AR 72701, United States
AB: Elastic ground deformation during the volcanic events associated with the 12-13 July 2003 world-record andesite dome collapse of Soufrière Hills Volcano, Montserrat, was measured by a network of continuous GPS receivers on the island. GPS data were collected and processed at 30 s intervals using kinematic analysis with GIPSY-OASIS II and JPL's high-rate orbit and clock parameters. Several sequences of rapid inflation, vulcanian explosion and synchronous collapse of the volcanic edifice were observed over the two days of eruption. Vertical, recoverable displacements of up to 1.8 m in an hour during the most vigorous intervals of activity were recorded at the most proximal site, approx. 1.6 km from the vent. CGPS data were used to model the deformations as Mogi source inflations and deflations. The data preclude a single Mogi source at any depth below the volcanic edifice, indicating a system with multiple, vertically-stacked sources, as well as some small contribution from the removal and redistribution of 210 Mm³ of rock constituting the andesite dome collapse.
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 8419 Volcano monitoring (7280)
DE: 8428 Explosive volcanism
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting