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| Titel |
Numerical tools for modelling the origins of seismic signals on volcanoes |
| VerfasserIn |
C. J. Bean, G. O'Brien |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250031369
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| Zusammenfassung |
| Multi-phase fluids play an important role in generating volcano-seismicity. Water, steam, gas and rock melt are by-products of the physical and chemical processes at work at active volcanoes. The interaction of these fluids with the surrounding rock can generate a multitude of seismic signals which are generally recorded at the surface. If they can be quantitatively interpreted, seismic signals can be used to help infer the activity-type and state of the volcano. However many seismic signals produced by these processes are still poorly understood, in a quantitative sense. This in part is due to a lack of numerical tools capable of handling systems which exhibit such complexity. In this talk we take a step towards filling this gap. We outline a method for mechanical fluid-rock interactions capable of generating static and dynamic (seismic) signals, which incorporates multi-phase fluids. The method combines an elastic-lattice scheme for dynamic and static elastic deformation with a lattice Boltzmann method for multi-phase fluid flow. As an example we model gas slug ascent in a vertical conduit demonstrating that this process is capable of generating LP and VLP like signals. A moment tensor inversion is performed on these synthetic VLP signals retrieving a source mechanism equivalent to that of a pipe structure. Hence these emerging schemes will help us to define implicit volcano source models in terms of ‘traditional’ seismological source descriptions. |
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