Title: | Variations of fluid pressure within the subducting oceanic crust and slow earthquakes |
Authors: | Kato, Aitaro Browse this author |
Iidaka, Takashi Browse this author |
Ikuta, Ryoya Browse this author |
Yoshida, Yasuhiro Browse this author |
Katsumata, Kei Browse this author →KAKEN DB |
Iwasaki, Takaya Browse this author |
Sakai, Shin'ichi Browse this author |
Thurber, Clifford Browse this author |
Tsumura, Noriko Browse this author |
Yamaoka, Koshun Browse this author |
Watanabe, Toshiki Browse this author |
Kunitomo, Takahiro Browse this author |
Yamazaki, Fumihito Browse this author |
Okubo, Makoto Browse this author |
Suzuki, Sadaomi Browse this author |
Hirata, Naoshi Browse this author |
Issue Date: | 29-Jul-2010 |
Publisher: | American Geophysical Union |
Journal Title: | Geophysical Research Letters |
Volume: | 37 |
Start Page: | L14310 |
Publisher DOI: | 10.1029/2010GL043723 |
Abstract: | We show fine‐scale variations of seismic velocities and converted teleseismic waves that reveal the presence of zones of high‐pressure fluids released by progressive metamorphic dehydration reactions in the subducting Philippine Sea plate in Tokai district, Japan. These zones have a strong correlation with the distribution of slow earthquakes, including long-term slow slip (LTSS) and low-frequency earthquakes (LFEs). Overpressured fluids in the LTSS region appear to be trapped within the oceanic crust by an impermeable cap rock in the fore-arc, and impede intraslab earthquakes therein. In contrast, fluid pressures are reduced in the LFE zone, which is deeper than the centroid of the LTSS, because there fluids are able to infiltrate into the narrow corner of the mantle wedge, leading to mantle serpentinization. The combination of fluids released from the subducting oceanic crust with heterogeneous fluid transport properties in the hanging wall generates variations of fluid pressures along the downgoing plate boundary, which in turn control the occurrence of slow earthquakes. |
Rights: | Copyright 2010 by the American Geophysical Union |
Type: | article |
URI: | http://hdl.handle.net/2115/50076 |
Appears in Collections: | 理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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