Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes?
Abstract When evaluating strong ground motions and tsunamis from specified source faults, it is required that the input parameters, such as fault geometry, rake angle, and slip amount, do not deviate from those of a real earthquake. Recently, a regional three-dimensional (3D) tectonic stress field w...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2024-02-01
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| Series: | Earth, Planets and Space |
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| Online Access: | https://doi.org/10.1186/s40623-023-01955-9 |
| _version_ | 1797275549805051904 |
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| author | Takeo Ishibe Toshiko Terakawa Akinori Hashima Masashi Mochizuki Ritsuko S. Matsu’ura |
| author_facet | Takeo Ishibe Toshiko Terakawa Akinori Hashima Masashi Mochizuki Ritsuko S. Matsu’ura |
| author_sort | Takeo Ishibe |
| collection | DOAJ |
| description | Abstract When evaluating strong ground motions and tsunamis from specified source faults, it is required that the input parameters, such as fault geometry, rake angle, and slip amount, do not deviate from those of a real earthquake. Recently, a regional three-dimensional (3D) tectonic stress field was used to estimate rake angles for mapped submarine faults with the Wallace–Bott hypothesis (WBH), the direction of fault slip was parallel to the resolved stress vector on a preexisting fault, and strong ground motions and tsunamis were simulated. However, this modeling technique has not been adequately validated. Additionally, it is necessary to examine how the stress field estimated from seismological data for a limited period (~ 10 years) can be used as a proxy for the long-term tectonic stress field. In this study, to provide such validation, we utilized two catalogs of focal mechanism solutions for earthquakes and compared the observed rake angles with those calculated from the regional 3D tectonic stress field with the WBH by fixing the fault strike and dip angles according to those from the focal mechanism data. The resulting misfit angles between the observed and calculated rake angles are generally small (ranging between − 30° and 30°), excluding several regions (e.g., the source and surrounding regions of the 2011 off the Pacific coast of Tohoku earthquake and swarm-like activities activated after the 2011 quake). We also confirmed that the calculated rake angles and classified fault types are consistent with geomorphologically and geologically evaluated types of faulting for major Quaternary active faults in the Kyushu district of southwest Japan. These results support the validity and effectiveness of estimating rake angles for a specific fault with known geometry from the above method and data, while also showing that close attention is needed to apply this method to, for example, seismically inactive regions where the inverted stress field includes significant uncertainties and/or near sites of recent and large earthquakes where the stress field has been perturbed. Graphical Abstract |
| first_indexed | 2024-03-07T15:15:01Z |
| format | Article |
| id | doaj.art-63fbded661c94b649e224d7288ef7719 |
| institution | Directory Open Access Journal |
| issn | 1880-5981 |
| language | English |
| last_indexed | 2024-03-07T15:15:01Z |
| publishDate | 2024-02-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Earth, Planets and Space |
| spelling | doaj.art-63fbded661c94b649e224d7288ef77192024-03-05T17:56:47ZengSpringerOpenEarth, Planets and Space1880-59812024-02-0176113910.1186/s40623-023-01955-9Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes?Takeo Ishibe0Toshiko Terakawa1Akinori Hashima2Masashi Mochizuki3Ritsuko S. Matsu’ura4Association for the Development of Earthquake PredictionNagoya UniversityTokyo Gakugei UniversityNational Research Institute for Earth Science and Disaster ResilienceAssociation for the Development of Earthquake PredictionAbstract When evaluating strong ground motions and tsunamis from specified source faults, it is required that the input parameters, such as fault geometry, rake angle, and slip amount, do not deviate from those of a real earthquake. Recently, a regional three-dimensional (3D) tectonic stress field was used to estimate rake angles for mapped submarine faults with the Wallace–Bott hypothesis (WBH), the direction of fault slip was parallel to the resolved stress vector on a preexisting fault, and strong ground motions and tsunamis were simulated. However, this modeling technique has not been adequately validated. Additionally, it is necessary to examine how the stress field estimated from seismological data for a limited period (~ 10 years) can be used as a proxy for the long-term tectonic stress field. In this study, to provide such validation, we utilized two catalogs of focal mechanism solutions for earthquakes and compared the observed rake angles with those calculated from the regional 3D tectonic stress field with the WBH by fixing the fault strike and dip angles according to those from the focal mechanism data. The resulting misfit angles between the observed and calculated rake angles are generally small (ranging between − 30° and 30°), excluding several regions (e.g., the source and surrounding regions of the 2011 off the Pacific coast of Tohoku earthquake and swarm-like activities activated after the 2011 quake). We also confirmed that the calculated rake angles and classified fault types are consistent with geomorphologically and geologically evaluated types of faulting for major Quaternary active faults in the Kyushu district of southwest Japan. These results support the validity and effectiveness of estimating rake angles for a specific fault with known geometry from the above method and data, while also showing that close attention is needed to apply this method to, for example, seismically inactive regions where the inverted stress field includes significant uncertainties and/or near sites of recent and large earthquakes where the stress field has been perturbed. Graphical Abstracthttps://doi.org/10.1186/s40623-023-01955-9Wallace–Bott hypothesisTectonic stress fieldRake anglesF-net mechanism solutionsJUNEC FM2Quaternary active faults |
| spellingShingle | Takeo Ishibe Toshiko Terakawa Akinori Hashima Masashi Mochizuki Ritsuko S. Matsu’ura Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes? Earth, Planets and Space Wallace–Bott hypothesis Tectonic stress field Rake angles F-net mechanism solutions JUNEC FM2 Quaternary active faults |
| title | Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes? |
| title_full | Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes? |
| title_fullStr | Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes? |
| title_full_unstemmed | Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes? |
| title_short | Can the regional 3D stress field according to the Wallace–Bott hypothesis predict fault slip directions of future large earthquakes? |
| title_sort | can the regional 3d stress field according to the wallace bott hypothesis predict fault slip directions of future large earthquakes |
| topic | Wallace–Bott hypothesis Tectonic stress field Rake angles F-net mechanism solutions JUNEC FM2 Quaternary active faults |
| url | https://doi.org/10.1186/s40623-023-01955-9 |
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