Biology and Medicine

Abstract

Characterization of Fine-grained Material Ejected by the Cotopaxi Volcano Employing X-ray Diffraction and Electron Diffraction Scattering Techniques

Andrea V. Vaca, Carlos R. Arroyo, Alexis Debut, Theofilos Toulkeridis, Luis Cumbal, Fernando Mato, Mario Cruz D’Howitt and Eduardo Aguilera

After 138 years of apparent silence, the Cotopaxi volcano awoke on August 14th of 2015 with a sequence of eruption events and the emission of both fine-grained volcanic material and gases. Four samples of the very first eruption were collected at different sites within the fallout area. The analysis of such samples, by using X-Ray Diffraction (XRD) as well as Electron Diffraction Scattering (EDS) techniques, allow us to determine the geochemical and mineralogical composition. On the basisthe presence of juvenile magma at the proximity of the crater has been categorically excluded. Therefore major eruptions and the subsequent generation of far-reaching lahars can be discarded for the duration of this volcanic stage.