Numerical reconstruction of the “Pómez Ezequiel Montes” Plinian fallout deposit: advantages in the use of numerical models for the reconstruction of fallout deposits from past eruptions

Abstract

A simple semi-analytical model (HAZMAP) for ash-fall deposit was applied to reconstruct the distribution of tephra deposits of the unit A of the SW lobe of the Pómez Ezequiel Montes Plinian eruption. This eruption, from the Amazcala caldera, represents one of the most important explosive events in the northern central sector of the Mexican Volcanic Belt where unit A is the thickest, more widely dispersed and well stratigraphically constrained fallout layer of this eruption. For this reason it represents a good candidate for the application of a semi-analytical model for the reconstruction of the isopach map and the eruptive parameters. The simulation results are in good agreement with estimations provided by other independent methods and were able to capture the actual deposit thickness and the effective total erupted mass, providing a closer approximation to more real eruptive parameters.