2016 Fiscal Year Final Research Report
Quantitative evaluation of earthquake induced phenomena based on fixed point measurement of shallow crustal stress
| Project/Area Number |
26289346
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Partial Multi-year Fund |
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| Section | 一般 |
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| Research Field |
Earth system and resources engineering
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| Research Institution | Tohoku University |
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Principal Investigator |
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| Co-Investigator(Kenkyū-buntansha) |
渡邉 則昭 東北大学, 環境科学研究科, 准教授 (60466539)
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| Research Collaborator |
YOKOYAMA Tatsuya 応用地質(株)
Lin Weiren JAMSTEC
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| Project Period (FY) |
2014-04-01 – 2017-03-31
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| Keywords | 地圧測定 / 地震 / 東北太平洋沖地震 / 絶対地圧 |
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| Outline of Final Research Achievements |
To examine the change in in-situ stress between before and after the 2011 Tohoku-oki earthquake, we performed stress measurements after the earthquake in the Kamaishi mine, located near the northern termination of the mainshock rupture. The in-situ stress measurement period was from 1991 to 2017. The results showed that the magnitudes of the three-dimensional principal stresses and the vertical stress drastically increased during the mainshock and, at one year after the earthquake, were more than double those before the earthquake. The principal stress magnitudes then decreased with time, and returned almost to the pre-earthquake levels at about five years after the earthquake. The increasing and decreasing trends in stress in the Kamaishi mine can be interpreted in terms of the effects of coseismic rupture behavior of the Tohoku-oki earthquake mainshock and the occurrence of aftershocks in the Sanriku-oki low-seismicity region (SLSR), where the Kamaishi mine is located.
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| Free Research Field |
ジオメカニクス
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