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Active open-vent volcanoes produce intense infrasound air- waves, and volcanoes with prominent craters can create strongly resonant signals, which are inaudible to humans, and often peak around 1 Hz. Study of volcano infrasound is used to model erup- tion dynamics, the structure of volcanic craters, and can be used as a component of volcano monitoring infrastructure. We have de- veloped a portable on-site real-time sonification device that emits an audible sound in response to an infrasonic airwave. This de- vice can be used near an active volcano both as a real-time edu- cational aid and as an accessible tool for monitoring the state of volcano activity. This paper presents this device with its hardware and software implementation, its parameter mapping sonification algorithm, recommendations for its use in the field, and strategies for future improvements.
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Volcano Opto‐Acoustics: Mapping the Infrasound Wavefield at Yasur Volcano (Vanuatu)
Abstract We explore the capabilities of volcano opto‐acoustics, a promising technique for measuring explosion and infrasound resonance phenomena at open‐vent volcanoes. Joint visual and infrasound study at Yasur Volcano (Vanuatu) demonstrate that even consumer‐grade cameras are capable of recording infrasound with high fidelity. Passage of infrasonic waves, ranging from as low as 5 Pa to hundreds of Pa, from both explosions and persistent tremor, pressurizes and depressurizes ambient plumes inducing visible vaporization and condensation respectively. Optical tracking of these pressure wavefields can be used to identify spectral characteristics, which vary within Yasur's two deep craters and are distinct for explosion and tremor sources. Wavefield maps can illuminate the propagation of blasts as well as the dynamics of persistent infrasonic tremor associated with standing waves in the craters. We propose that opto‐acoustic monitoring is useful for extraction of near‐vent infrasound signal and for tracking volcanic unrest from a remote distance.
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- Award ID(s):
- 1830976
- PAR ID:
- 10409569
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 50
- Issue:
- 8
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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