Steady subsidence of a repeatedly erupting caldera through InSAR observations: Aso, Japan
Authors
Nobile, A.
Acocella, V.
Ruch, J.
Aoki, Y.
Borgstrom, S.
Siniscalchi, V.
Geshi, N.
Discipline
Earth and related Environmental sciences
Subject
Natural hazards
Audience
Scientific
Date
2017Publisher
Springer
Metadata
Show full item recordDescription
The relation between unrest and eruption at calderas is still poorly understood. Aso caldera, Japan, shows minor episodic phreatomagmatic eruptions associated with steady subsidence. We analyse the deformation of Aso using SAR images from 1993 to 2011 and compare it with the eruptive activity. Although the dataset suffers from limitations (e.g. atmospheric effects, coherence loss, low signal-to-noise ratio), we observe a steady subsidence signal from 1996 to 1998, which suggests an overall contraction of a magmatic source below the caldera centre, from 4 to 5 km depth. We propose that the observed contraction may have been induced by the release of the magmatic fluids feeding the eruptions. If confirmed by further data, this hypothesis suggests that degassing processes play a crucial role in triggering minor eruptions within open conduit calderas, such as at Aso. Our study underlines the importance of defining any eruptive potential also from deflating magmatic systems with open conduit.
Citation
Nobile, A.; Acocella, V.; Ruch, J.; Aoki, Y.; Borgstrom, S.; Siniscalchi, V.; Geshi, N. (2017). Steady subsidence of a repeatedly erupting caldera through InSAR observations: Aso, Japan. , Bulletin of Volcanology, Vol. 79:32, Springer, DOI: 10.1007/s00445-017-1112-1.Identifiers
Type
Article
Peer-Review
Yes
Language
eng