Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence
Foreshocks and aftershocks occurred before and after the ML6.8 (Mw7.0) earthquake in eastern Taiwan on 18 September 2022. We explore the epicentral distribution and temporal variations for the mainshock, foreshocks, and aftershocks. Most of the events were located in the area around the Longitudinal...
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Frontiers Media S.A.
2024-03-01
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| Series: | Frontiers in Earth Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/feart.2024.1327943/full |
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| author | Kou-Cheng Chen Bor-Shouh Huang Kwang-Hee Kim Jeen-Hwa Wang Jeen-Hwa Wang |
| author_facet | Kou-Cheng Chen Bor-Shouh Huang Kwang-Hee Kim Jeen-Hwa Wang Jeen-Hwa Wang |
| author_sort | Kou-Cheng Chen |
| collection | DOAJ |
| description | Foreshocks and aftershocks occurred before and after the ML6.8 (Mw7.0) earthquake in eastern Taiwan on 18 September 2022. We explore the epicentral distribution and temporal variations for the mainshock, foreshocks, and aftershocks. Most of the events were located in the area around the Longitudinal Valley. Most foreshocks occurred around the mainshock, while the aftershocks happened outwards from the foreshock area. The temporal variations in seismic-wave energy show that the largest foreshock and the mainshock were responsible for releasing most of the energy during the earthquake sequence. In addition, the b values of the Gutenberg-Richter frequency-magnitude law were 0.62 for foreshocks, 0.87 for aftershocks, and 0.71 for the whole seismic activity by using the least squares method and 0.52 for foreshocks, 0.84 for aftershocks, and 0.65 for the whole seismic activity by using the maximum likelihood method. The b values increase from foreshocks to aftershocks, suggesting the possibility that the fluid pressure of faults during foreshocks is higher than that of the faults during aftershocks due to the outward migration of water. The p-value of the Omori-Utsu law for the aftershock sequence was estimated to be 0.92 for all aftershocks in the study, 1.39 for the aftershocks occurred in the first 6 days, and 1.30 for the aftershocks occurred in the first 12 days. The foreshock sequence could not be described by the inverse Omori law. |
| first_indexed | 2024-03-07T16:22:33Z |
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| id | doaj.art-4e885be6f4554e02a62a2c28179e7318 |
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| language | English |
| last_indexed | 2024-03-07T16:22:33Z |
| publishDate | 2024-03-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-4e885be6f4554e02a62a2c28179e73182024-03-04T04:46:04ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632024-03-011210.3389/feart.2024.13279431327943Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequenceKou-Cheng Chen0Bor-Shouh Huang1Kwang-Hee Kim2Jeen-Hwa Wang3Jeen-Hwa Wang4Institute of Earth Sciences, Academia Sinica, Nangang, TaiwanInstitute of Earth Sciences, Academia Sinica, Nangang, TaiwanDepartment of Geological Sciences, Pusan National University, Pusan, Republic of KoreaInstitute of Earth Sciences, Academia Sinica, Nangang, TaiwanDepartment of Earth Sciences, National Central University, Taoyuan, TaiwanForeshocks and aftershocks occurred before and after the ML6.8 (Mw7.0) earthquake in eastern Taiwan on 18 September 2022. We explore the epicentral distribution and temporal variations for the mainshock, foreshocks, and aftershocks. Most of the events were located in the area around the Longitudinal Valley. Most foreshocks occurred around the mainshock, while the aftershocks happened outwards from the foreshock area. The temporal variations in seismic-wave energy show that the largest foreshock and the mainshock were responsible for releasing most of the energy during the earthquake sequence. In addition, the b values of the Gutenberg-Richter frequency-magnitude law were 0.62 for foreshocks, 0.87 for aftershocks, and 0.71 for the whole seismic activity by using the least squares method and 0.52 for foreshocks, 0.84 for aftershocks, and 0.65 for the whole seismic activity by using the maximum likelihood method. The b values increase from foreshocks to aftershocks, suggesting the possibility that the fluid pressure of faults during foreshocks is higher than that of the faults during aftershocks due to the outward migration of water. The p-value of the Omori-Utsu law for the aftershock sequence was estimated to be 0.92 for all aftershocks in the study, 1.39 for the aftershocks occurred in the first 6 days, and 1.30 for the aftershocks occurred in the first 12 days. The foreshock sequence could not be described by the inverse Omori law.https://www.frontiersin.org/articles/10.3389/feart.2024.1327943/fullforeshockaftershockepicentral distributionseismic-wave energyb-valuep-value |
| spellingShingle | Kou-Cheng Chen Bor-Shouh Huang Kwang-Hee Kim Jeen-Hwa Wang Jeen-Hwa Wang Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence Frontiers in Earth Science foreshock aftershock epicentral distribution seismic-wave energy b-value p-value |
| title | Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence |
| title_full | Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence |
| title_fullStr | Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence |
| title_full_unstemmed | Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence |
| title_short | Some characteristics of foreshocks and aftershocks of the 2022 ML6.8 Chihshang, Taiwan, earthquake sequence |
| title_sort | some characteristics of foreshocks and aftershocks of the 2022 ml6 8 chihshang taiwan earthquake sequence |
| topic | foreshock aftershock epicentral distribution seismic-wave energy b-value p-value |
| url | https://www.frontiersin.org/articles/10.3389/feart.2024.1327943/full |
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