Depth variations in seismic velocity in the subducting crust : Evidence for fluid-related embrittlement for intermediate-depth earthquakes
Bibliographic Information
- Other Title
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- Depth variations in seismic velocity in the subducting crust: Evidence for fluid‐related embrittlement for intermediate‐depth earthquakes
Abstract
We investigated seismic wave velocity in the subducting crust of the Pacific slab beneath eastern Hokkaido, northern Japan. To detect depth-dependent properties of the seismic velocities in the crust, we analyzed guided waves that propagate in the crust and estimated P wave velocity (V-p) of 6.5-7.5km/s and S wave velocity (V-s) of 3.6-4.2km/s at depths of 50-100km. The results show that the obtained V-p and V-s are 10-15% lower than those expected for the fully hydrated mid-ocean ridge basalt, suggesting the existence of aqueous fluids by similar to 1 vol % in the crust at this depth range. Our observations suggest that overpressurized fluids channeled in the subducting crust plays as a dominant factor for facilitating the genesis of crustal earthquakes at intermediate depths.
Journal
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- Geophysical research letters
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Geophysical research letters 44 (2), 810-817, 2017-01-28
American Geophysical Union
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Details 詳細情報について
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- CRID
- 1050282813999632512
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- NII Article ID
- 120006329011
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- ISSN
- 19448007
- 00948276
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- HANDLE
- 2115/66865
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- Text Lang
- en
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- Article Type
- journal article
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- Data Source
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- IRDB
- Crossref
- CiNii Articles
- KAKEN