Slope Stability Finite Element Modeling of El Misti Volcano, Peru

Hollander J.A.; Walton G.; Villeneuve M.; Salas G.; Luza C. · 58th US Rock Mechanics / Geomechanics Symposium 2024, ARMA 2024 (2024) · DOI: 10.56952/arma-2024-0811

Resumen

El Misti is a 5822 m elevation symmetrical, andesitic stratovolcano located near the city of Arequipa in Peru. Numerous historic debris and avalanche deposits indicate that the volcano slopes could be unstable, and that seismic or volcanogenic activity might have the potential to trigger movement that could threaten Arequipa. To evaluate this potential, a cross-section was first developed along a transect from the summit southwest towards Arequipa based on available geologic information. The stability of the southwestern slope of El Misti approaching Arequipa was then investigated using 2D finite element homogenized continuum modeling. The shear strength reduction (SSR) method was used to find critical strength reduction factors (SRF) at which the slope is marginally stable (SRF ~ 1) given a pseudo-static seismic loading based on the peak ground acceleration (PGA) for Arequipa. Possible mechanisms of slope failure for different assigned subsurface conditions were investigated. Copyright 2024 ARMA, American Rock Mechanics Association.

Instituciones: Universidad Nacional de San Agustín de Arequipa