| Project/Area Number |
17310104
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Natural disaster science
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| Research Institution | Tohoku University |
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Principal Investigator |
HIRANO Shin-ichi Tohoku University, Graduate School of Science Earth Science, Associate Professor (10228801)
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| Co-Investigator(Kenkyū-buntansha) |
MATSUMOTO Hideaki Tohoku Gakuin University, Faculty of Liberal Arts, Professor (30173909)
KOIWA Naoto Hirosaki University, Faculty of Education, Associate Professor (70296002)
MURAYAMA Yoshiyuki Yamagata University, Faculty of Education, Art and Science, Associate Professor (10210072)
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| Project Period (FY) |
2005 – 2007
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| Project Status |
Completed (Fiscal Year 2007)
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| Budget Amount *help |
¥13,510,000 (Direct Cost: ¥12,400,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2007: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2006: ¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2005: ¥4,600,000 (Direct Cost: ¥4,600,000)
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| Keywords | Seismic hazard / active fault |
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| Research Abstract |
Northeastern Japan is one of the most typical island arc-trench systems. The primary active faults of the Tohoku region lie at the boundaries of the mountains and the lowland, and most of these run in a north-south direction. Most are reverse faults, indicating that the area is uniformly being compressed in an east-west direction. This research is to clarify the precise location and Late Pleistocene-Holocene activity of the reverse fault for the reduction of the damage related to ground condition. The study areas are as follows; Nagamachi-Rifu Line fault zone, marginal fault zone of the western Fukushima basin and the Tsugaru mountains area.
1. The Nagamachi-Rifu Line fault zone is an active fault system running through the urban area of Sendai, it stretches with the direction of NE-SW. Several river terraces and recent back marsh surface (alluvial plain) have deformed by the fault zone. The last seismic activity of the Nagamachi-Rifu Line fault probably has not moved since at least abo
… More
ut2,600^<14>C years B. P. based on the borehole survey across the fault. And the coseismic uplift reached1.4m as derived from a topographic profile measured perpendicular to the trace of the fault scarplet. Moreover the upper limit of the alluvial basal gravel bed is offset by the fault and shows3.2m.
2. In the western margin of the Fukushima basin, several faults delineate the boundary between the mountain and basin area. In the northern part of the Fukushima basin, the fault zone is made up the Fujita Higashi fault and the Kori fault. It stretches in the direction NE-SW.
The radiocarbon ages indicate that the timing of the last faulting event occurred after3,300^<14>C years B. P. And the displacement was about1.3m.
3. The Kuroishi fault locates at the western boundary region of the Tsugaru mountains. It stretches with high certainty in the direction of N・S,23kilometers long. The vertical offset of the Holocene terraces are 0.4to 0.8m. Moreover the displacement of the strata located about 10m in depth is1.0to1.5m. The average slip rate of the fault is smaller than that of a previous presumption.
4. In the Aomori alluvial plain, it was clarified that the acceleration increase in soft soil such as abandoned channel based on the observation of the seismometer. Less
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