Eruption type probability and eruption source parameters at Cotopaxi and Guagua Pichincha volcanoes (Ecuador) with uncertainty quantification

Future occurrence of explosive eruptive activity at Cotopaxi and Guagua Pichincha volcanoes, Ecuador, is assessed probabilistically, utilizing expert elicitation. Eight eruption types were considered for each volcano. Type event probabilities evaluated the next volcano least one type within 100 years. For type, we elicited relevant source parameters (duration, average plume height, total tephra mass). We investigated robustness these evaluations by deriving probability uncertainties using three scoring methods. Cotopaxi, both rhyolitic andesitic magmas. Elicitation findings indicate that most probable an hydrovolcanic/ash-emission (~ 26–44% median probability), which has also highest recurring over However, joint sub-Plinian or Plinian order 30–40%—a significant chance a violent event. It inferred any could involve longer duration greater erupted mass than event, likely producing prolonged emergency. Pichincha, future are expected to be andesitic/dacitic, vulcanian judged (median ~40–55%); this frequent years, too. there substantial (possibly >40% in average) Plinian, with all implies hazard levels.