2017 Fiscal Year Final Research Report
Evaluation on the structural features of active fault damage zone and activity of faults.
Project/Area Number |
15K01248
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Natural disaster / Disaster prevention science
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Research Institution | Kyoto University |
Principal Investigator |
Lin Aiming 京都大学, 理学研究科, 教授 (90283861)
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Project Period (FY) |
2015-04-01 – 2018-03-31
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Keywords | 活断層 / 断層破砕帯 / 地震断層 / 脈状断層岩 / 断層摩擦熱 / 流体化作用 / 震源断層 / 断層物性 |
Outline of Final Research Achievements |
Based on field investigations and meso- and microstructural analyses of fault zones of the active Nojima Fault and Arima-Takatsuki Tectonic Line active fault system, the following results have been obtained: 1) the vein networks of pseudotachylyte with both melt and crush origins, as well as ultracataclastic rocks formed by rapid injection of ultrafine- to fine-grained material are sourced from pulverized ultracataclastic rocks in seismogenic fault zones under thermal pressurization and fluidization during seismic faulting; 2) the fault damage zones of both faults have been strongly pulverized; 3) the recurrence interval of large earthquakes in the Nojima Fault is inferred to be =900~1000 years that are shorter than that previously reported; 4) the 1596 Keicho-Fushimi earthquake probably ruptured the western segment around the Arima-Spring. Field investigations also demonstrated that the Mw 7.1 2016 Kumamoto earthquake ruptures the preexisting active faults.
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Free Research Field |
地震地質学
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