Edifice Sector Failure at Soufriere Hills Volcano, Montserrat: Documenting the Failure Dynamics of a Hydrothermally-Altered Edifice in Three-Dimensions

Pennsylvania State Univ University Park, University Park PA

Investigators

Abstract

9909673 Voight and Elsworth The potential for catastrophic structural failure of volcanoes and related hazards implications are now well recognized, but apart from a study at Mount St Helens, the mechanisms of collapse are poorly understood. The major edifice failure on Montserrat in December 1997 provides an unusual opportunity for a comprehensive analysis of collapse. The failure occurred on the altered south flank of Soufriere Hills volcano, generated a debris avalanche that reached the coast, and triggered a volcanic blast. The failure has been well documented, and abundant volcano monitoring data have been collected by Montserrat Volcano Observatory; one of us, BV, is a member of this organization. We propose to analyze the deformation and stability of this volcano, using powerful computer-modeling tools not used previously in volcano analyses. The study will evaluate realistic models representing gradual to sudden collapse, examine the effects of earthquake loading in a rigorous fashion, and consider the potential for collapse prediction from monitored data. The results of this study are likely to have a significant impact on evaluations of potential structural failure at other volcanoes, with an important bearing on volcano hazard management.