Investigating the effects of event scale and vent location on pyroclastic density current hazard maps of Campi Flegrei caldera (Italy)

Abstract

Campi Flegrei (CF) is an active, densely populated, caldera with very high risks associated with the occurrence of pyroclastic density currents (PDCs). Mapping of PDCs hazard in caldera settings is challenging due to the large uncertainty on future eruption scale and vent location as well as the complex dynamics of flows over caldera topography. First background probability maps of PDC invasion were produced adopting a vent-opening probability map, with associated uncertainty, of the whole caldera based on the eruptive record of the last 15 kyr. Maps were produced by a Monte Carlo approach by using a simplified inundation model based on the “box model” approximation tuned to results from 2D transient numerical simulations of flow dynamics. In this presentation we illustrate the independent effects of event scale and vent location, as well as of possible correlations between them, on the resulting invasion maps. The analysis allowed to identify areas with elevated probabilities of flow invasion as a function of the diverse assumptions made. With quantification of some sources of uncertainty in relation to the system, we were able also to provide mean and percentile maps of PDC hazard levels.