Laboratory simulation of volcano seismicity.
The physical processes generating seismicity within volcanic edifices are highly complex and not fully understood. We report results from a laboratory experiment in which basalt from Mount Etna volcano (Italy) was deformed and fractured. The experiment was monitored with an array of transducers around the sample to permit full-waveform capture, location, and analysis of microseismic events. Rapid post-failure decompression of the water-filled pore volume and damage zone triggered many low-frequency events, analogous to volcanic long-period seismicity. The low frequencies were associated with pore fluid decompression and were located in the damage zone in the fractured sample; these events exhibited a weak component of shear (double-couple) slip, consistent with fluid-driven events occurring beneath active volcanoes.
Benson
Philip M
PM
Rock and Ice Physics Laboratory, Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, UK. p.benson@ucl.ac.uk
Vinciguerra
Sergio
S
Meredith
Philip G
PG
Young
R Paul
RP