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Source mechanism of very-long-period signals accompanying dome growth activity at Merapi volcano, Indonesia

D. Hidayat·B. Chouet·B. Voight·P. Dawson·Antonius Ratdomopurbo
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Abstract

Very-long-period (VLP) pulses with period of 6–7s, displaying similar waveforms, were identified in 1998 from broadband seismographs around the summit crater. These pulses accompanied most of multiphase (MP) earthquakes, a type of long-period event locally defined at Merapi Volcano. Source mechanisms for several VLP pulses were examined by applying moment tensor inversion to the waveform data. Solutions were consistent with a crack striking ∼70° and dipping ∼50° SW, 100m under the active dome, suggest pressurized gas transport involving accumulation and sudden release of 10–60 m 3 of gas in the crack over a 6s interval.

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D. Hidayat, B. Chouet, B. Voight, P. Dawson, Antonius Ratdomopurbo. 2002-12-11. Source mechanism of very-long-period signals accompanying dome growth activity at Merapi volcano, Indonesia. https://doi.org/10.1029/2002gl015013

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