Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea
An MW 5.5 earthquake occurred in Pohang, Korea, on 15 November 2017 and caused large damage. In and around the epicentral area the earthquake also remained numerous sand boils, which is a surface representation of soil liquefaction at shallow depth during the earthquake. Soil liquefaction is one of...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-11-01
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| Series: | Frontiers in Earth Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/feart.2022.1029996/full |
| _version_ | 1798023105620213760 |
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| author | Su Young Kang Kwang-Hee Kim Yong Sik Gihm Byungmin Kim |
| author_facet | Su Young Kang Kwang-Hee Kim Yong Sik Gihm Byungmin Kim |
| author_sort | Su Young Kang |
| collection | DOAJ |
| description | An MW 5.5 earthquake occurred in Pohang, Korea, on 15 November 2017 and caused large damage. In and around the epicentral area the earthquake also remained numerous sand boils, which is a surface representation of soil liquefaction at shallow depth during the earthquake. Soil liquefaction is one of the most dangerous consequences of an earthquake. Here we show that the spatial distribution of the ground vulnerability index (Kg), which we estimate via ambient noise analysis, correlates very well with the distribution of sand boils. Our Kg model based on the dense microtremor surveys at differing geological conditions and urbanizations indicates that only 28.4% of the study area is vulnerable to ground shaking (Kg > 20), with 91.1% of the observed sand boils occurring in these vulnerable areas. We also observed that Kg values estimated in the study correlate well with both VS30 values and geologic units in the study area. This case report confirmed that the Kg can be an affordable supplement to traditional, but expensive and time-consuming, geotechnical/geophysical techniques for the initial screening and regional evaluations. Such a Kg map can assist stakeholders in earthquake-prone regions in identifying areas more susceptible to liquefaction and bring a recommendation to consider seismic hazard mitigation. |
| first_indexed | 2024-04-11T17:40:56Z |
| format | Article |
| id | doaj.art-2e6c0e1ada5f469595ce0008b9253657 |
| institution | Directory Open Access Journal |
| issn | 2296-6463 |
| language | English |
| last_indexed | 2024-04-11T17:40:56Z |
| publishDate | 2022-11-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-2e6c0e1ada5f469595ce0008b92536572022-12-22T04:11:29ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632022-11-011010.3389/feart.2022.10299961029996Soil liquefaction potential assessment using ambient noise: A case study in Pohang, KoreaSu Young Kang0Kwang-Hee Kim1Yong Sik Gihm2Byungmin Kim3Institute of Geohazard Research, Pusan National University, Busan, KoreaDepartment of Geological Sciences, Pusan National University, Busan, KoreaSchool of Earth System Science, Kyungpook National University, Daegu, KoreaDepartment of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, Ulsan, KoreaAn MW 5.5 earthquake occurred in Pohang, Korea, on 15 November 2017 and caused large damage. In and around the epicentral area the earthquake also remained numerous sand boils, which is a surface representation of soil liquefaction at shallow depth during the earthquake. Soil liquefaction is one of the most dangerous consequences of an earthquake. Here we show that the spatial distribution of the ground vulnerability index (Kg), which we estimate via ambient noise analysis, correlates very well with the distribution of sand boils. Our Kg model based on the dense microtremor surveys at differing geological conditions and urbanizations indicates that only 28.4% of the study area is vulnerable to ground shaking (Kg > 20), with 91.1% of the observed sand boils occurring in these vulnerable areas. We also observed that Kg values estimated in the study correlate well with both VS30 values and geologic units in the study area. This case report confirmed that the Kg can be an affordable supplement to traditional, but expensive and time-consuming, geotechnical/geophysical techniques for the initial screening and regional evaluations. Such a Kg map can assist stakeholders in earthquake-prone regions in identifying areas more susceptible to liquefaction and bring a recommendation to consider seismic hazard mitigation.https://www.frontiersin.org/articles/10.3389/feart.2022.1029996/fullearthquakessoil liquefactionseismic hazardground vulnerabilityhorizontal-to-vertical spectral ratio |
| spellingShingle | Su Young Kang Kwang-Hee Kim Yong Sik Gihm Byungmin Kim Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea Frontiers in Earth Science earthquakes soil liquefaction seismic hazard ground vulnerability horizontal-to-vertical spectral ratio |
| title | Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea |
| title_full | Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea |
| title_fullStr | Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea |
| title_full_unstemmed | Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea |
| title_short | Soil liquefaction potential assessment using ambient noise: A case study in Pohang, Korea |
| title_sort | soil liquefaction potential assessment using ambient noise a case study in pohang korea |
| topic | earthquakes soil liquefaction seismic hazard ground vulnerability horizontal-to-vertical spectral ratio |
| url | https://www.frontiersin.org/articles/10.3389/feart.2022.1029996/full |
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