Deep downward fluid percolation driven by localized crust dilatation in Iceland
International audience From a detailed seismic survey on a transform-like plate setting in Iceland, we propose a spatial relationship between highly deformed crustal columns and areas of low Vp/Vs ratio, which are best explained by high fluid pressures at the base of the seismogenic crust. Combined...
Published in: | Geophysical Research Letters |
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Main Authors: | , |
Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2008
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Subjects: | |
Online Access: | https://hal.archives-ouvertes.fr/hal-00323602 https://hal.archives-ouvertes.fr/hal-00323602/document https://hal.archives-ouvertes.fr/hal-00323602/file/2008GL034514.pdf https://doi.org/10.1029/2008GL034514 |
Summary: | International audience From a detailed seismic survey on a transform-like plate setting in Iceland, we propose a spatial relationship between highly deformed crustal columns and areas of low Vp/Vs ratio, which are best explained by high fluid pressures at the base of the seismogenic crust. Combined with geological observations, our seismic data suggest transient and local increases in crust permeability at specific highly dilating areas triggered by dynamical stresses from high-magnitude regional earthquakes. Fluids are then trapped at supercritical conditions in the deep brittle crust which, in turn, increases the capacity of the rocks to deform through cracking and faulting. |
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