Presenter: Aprilia Nurmawati
Date: 2016/12/01
Abstract
Hydrothermal explosions frequently occurs in geothermal area. The various mechanisms can be identified by investigating the explosivity. The dynamics and energy of the explosion are inferred from the deposits. Furthermore the lithology of the geothermal system also controls the efficiency in the energy release during an explosion. Here the energy of the explosion is considered as properties of an isolated system. This energy is then evaluated to get the energy conversion ratio as the energy is partitioned into several parts, such as energy to create crater, kinetic energy to eject the Volcanic Ballistic Projectiles (VBP), and seismic energy. The example of 2013 Gengissig lake events shows a multidisciplinary approach combining detailed field work, laboratory studies and explosion models. The comparison of field work data and the result from models yields a robust constraints on the explosion energy. The detailed mapping of the deposits show good estimations of the ejected mass and volume, which are also reasonably consistent to theoretical models.
Reference
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