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Seismic and experimental insights into eruption precursors at Volcan de Colima.

ABSTRACT: We combine geophysical and experimental observations to interpret preeruptive unrest at Volcán de Colima in 1998. 17,893 volcanic earthquakes were detected between 1 October and 31 December 1998, including 504 clusters. Using seismic ambient noise interferometry, we observe a drop in velocity prior to the eruption linked to damage accumulation during magma ascent. This is supported by experimental observations where static stress causes a velocity decrease prior to failure. Furthermore, we observe acoustic emission clusters during the experiments, with lower porosity samples producing higher numbers of repeaters. This behavior introduces tensile failure as an additional viable mechanism for clusters during magma ascent. The findings suggest that preeruptive magma ascent may be monitored to variable degrees of accuracy via descriptions of damage accumulation and associated seismic velocity changes.

SUBMITTER: Lamb OD

PROVIDER: S-EPMC6108408 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Seismic and experimental insights into eruption precursors at Volcán de Colima.

Lamb Oliver D OD De Angelis Silvio S Wall Richard J RJ Lamur Anthony A Varley Nick R NR Reyes-Dávila Gabriel G Arámbula-Mendoza Raúl R Hornby Adrian J AJ Kendrick Jackie E JE Lavallée Yan Y

Geophysical research letters 20170601 12

We combine geophysical and experimental observations to interpret preeruptive unrest at Volcán de Colima in 1998. 17,893 volcanic earthquakes were detected between 1 October and 31 December 1998, including 504 clusters. Using seismic ambient noise interferometry, we observe a drop in velocity prior to the eruption linked to damage accumulation during magma ascent. This is supported by experimental observations where static stress causes a velocity decrease prior to failure. Furthermore, we obser ...[more]

PMID: 30166740

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Dataset Information

Seismic and experimental insights into eruption precursors at Volcan de Colima.

Publications

Seismic and experimental insights into eruption precursors at Volcán de Colima.

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