ARTÍCULO
Flank collapse scenarios at Volcán de Colima, Mexico: A relative instability analysis
Lorenzo Borselli, Lucia Capra,Damiano Sarocchi , Servando De la Cruz-Reyna
Journal of Volcanology and Geothermal Research 208 pp. (51-65), 2011.
ABSTRACT:
Previous studies on de bris avalanche deposits of Volcán de Colima suggest acyclic process of repetitive flank collapse striggered by majore ruptions(VEIN4). The recurrence interval o f major collapse events during the last 10,000 years is calculated here using a sto chastic approach, yielding amean recurrence interval of 2698yr,with an uncertainty range of 180yr. The analysis yields an increased probability of flank collapse in the interval between −110yrand+345yr from the present. This generates a series of scenarios ranging from optimistic, considering a collapse with in the next 345years,to pessimistic,derived from the 110year delay. The analysis of relative mass/volume deficit in the volcano structure, made using the new VOLCANOFIT 2.0 software, and a limit equilibrium analysis on the volcano flanks point to the SW quadrant as potentially the most unstable sector of the edifice under a wide range of scenarios. The TITAN2D numerical modelis also used to simulate the extent of debris avalanches caused by failure of the SW flank. This approach may be applied to any volcano with a potential for flank collapse.