HR: 0800h
AN: V31E-0710    [Abstracts]
TI: Calm Before the Storm? Immediate Identification of Volcanic Eruption Intensity: Promising Test of a New Monitoring System at the Active Volcano Popocatépetl, Mexico
AU: * Berger, P
EM: pia.berger@gmail.com
AF: Instituto de Geofisica, UNAM Ciudad Universitaria, Coyoacan, Mexico City, DF 04510, Mexico
AB: Experiments by the Physikalisch Vulkanologisches Labor (PVL) in Wuerzburg, Germany, have shown that the intensity of violent volcanic eruptions, occurring when magma undergoes brittle fragmentation, is mirrored within brief electrical charges that can be detected on a short timescale (ms). Laboratory studies and certain explosion experiments offer the opportunity to calibrate the energy release of volcanic eruptions. Based on these results, a new high-precision, low-cost, real-time surveillance system is developed and tested at the active volcano of Popocat\´{e}petl, Mexico. This volcano, situated about 60 km southeast of Mexico City, offers excellent testing conditions, erupting regularly and intensively and violent eruptions are expected in the near future. The system, which detects short-term electrostatic field gradients (dc voltage against local ground), mainly consists of an antenna and a specially-designed amplifier. Depending on eruption intensity, as little as two or three eruptions will provide a sufficient amount of data. Amount, size, and shape of erupted particles give important indications about the physical fragmentation process which formed the pyroclasts, and hence about the type and intensity of the eruption. The evaluation and analysis of the samples collected at the volcano after each documented eruption will be carried out at the PVL. This physics lab, with a specially-designed experimental setup, allows controlled explosion experiments wherein rock from lava or bombs - related to the sampled pyroclasts - will be melted and subsequently brought to explosion. The energy released during these laboratory experiments will be calibrated to Popocat\´{e}petl using the ejecta volume of the observed eruptions, allowing a correlation of the actual energy release to the registered electrical field data. The aims of the project are: (1) quantification of individual magma properties of Popocat\´{e}petl (2) on-line measurement of mechanical energy release and mass flux and (3) immediate risk assessment of ongoing volcanic eruptions using permanent sensors located on volcanoes with pyroclastic eruptions.
DE: 8404 Volcanoclastic deposits
DE: 8411 Thermodynamics (0766, 1011, 3611)
DE: 8419 Volcano monitoring (7280)
DE: 8445 Experimental volcanism
DE: 8494 Instruments and techniques
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting