| Project/Area Number |
18K03810
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Review Section |
Basic Section 17040:Solid earth sciences-related
|
|---|
| Research Institution | Geospatial Information Authority of Japan (Geography and Crustal Dynamics Research Center) |
|---|
Principal Investigator |
Kobayashi Tomokazu 国土地理院(地理地殻活動研究センター), その他部局等, 研究室長 (40447991)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
安藤 亮輔 東京大学, 大学院理学系研究科(理学部), 准教授 (10455256)
松尾 功二 国土地理院(地理地殻活動研究センター), その他部局等, 主任研究官 (80722800)
中埜 貴元 国土地理院(地理地殻活動研究センター), その他部局等, 研究官 (60511962)
|
|---|
| Project Period (FY) |
2018-04-01 – 2023-03-31
|
| Project Status |
Completed (Fiscal Year 2022)
|
| Budget Amount *help |
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Fiscal Year 2019: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2018: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
|
|---|
| Keywords | 断層破壊の停止 / 内陸地震 / 火山 / 地殻変動 / ＳＡＲ / 重力 / 密度構造 / 3次元動的破壊数値シミュレーション / 熊本地震 / 阿蘇カルデラ / 断層破壊 / 測地観測 / 数値計算 |
|---|
| Outline of Final Research Achievements |
Conducting crustal deformation analysis using synthetic aperture radar satellite data, we have successfully revealed that the fault slip for the 2016 Kumamoto earthquake progressively converged just after penetrating a few km into the Aso caldera. We inferred the density contrast structure using gravity data, and found that a low-density body exists in the shallow part of the western edge of the caldera at a depth of a few km. The fault slip penetrated the low-density region, and then dissipated. It is suggested that a hydrothermal environment has developed in the region, resulting in a high-temperature crustal structure which could prevent from further brittle rupture. Our numerical simulation of dynamic rupture indicates that the presence of low stress field in the caldera is closely related to the terminus of fault rupture.
|
| Academic Significance and Societal Importance of the Research Achievements |
内陸地震における断層末端のすべりの様子とその周囲の地殻構造を従来にない高い空間分解能で捉えたことにより、火山地域における高温の地熱地帯が断層破壊の停止に強く関与していたことを明らかにした。このことは、地震と火山の相互作用が断層破壊の停止の要因を考える上で重要な視点となり得ることを当該研究分野に示すものである。
|
