{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T12:12:34Z","timestamp":1775477554682,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,19]],"date-time":"2019-09-19T00:00:00Z","timestamp":1568851200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and ICT, Republic of Korea.","award":["1711051627"],"award-info":[{"award-number":["1711051627"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>On 15 November 2017, liquefaction phenomena were observed around the epicenter after a 5.4 magnitude earthquake occurred in Pohang in southeast Korea. In this study, we attempted to detect areas of sudden water content increase by using SAR (synthetic aperture radar) and optical satellite images. We analyzed coherence changes using Sentinel-1 SAR coseismic image pairs and analyzed NDWI (normalized difference water index) changes using Landsat 8 and Sentinel-2 optical satellite images from before and after the earthquake. Coherence analysis showed no liquefaction-induced surface changes. The NDWI time series analysis models using Landsat 8 and Sentinel-2 optical images confirmed liquefaction phenomena close to the epicenter but could not detect liquefaction phenomena far from the epicenter. We proposed and evaluated the TDLI (temporal difference liquefaction index), which uses only one SWIR (short-wave infrared) band at 2200 nm, which is sensitive to soil moisture content. The Sentinel-2 TDLI was most consistent with field observations where sand blow from liquefaction was confirmed. We found that Sentinel-2, with its relatively shorter revisit period compared to that of Landsat 8 (5 days vs. 16 days), was more effective for detecting traces of short-lived liquefaction phenomena on the surface. The Sentinel-2 TDLI could help facilitate rapid investigations and responses to liquefaction damage.<\/jats:p>","DOI":"10.3390\/rs11182184","type":"journal-article","created":{"date-parts":[[2019,9,19]],"date-time":"2019-09-19T10:55:21Z","timestamp":1568890521000},"page":"2184","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Detection of Liquefaction Phenomena from the 2017 Pohang (Korea) Earthquake Using Remote Sensing Data"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9282-6947","authenticated-orcid":false,"given":"Hyunseob","family":"Baik","sequence":"first","affiliation":[{"name":"Department of Geophysical Exploration, KIGAM campus, Korea University of Science and Technology (UST), Daejeon 34114, Korea"},{"name":"Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Korea"}]},{"given":"Young-Sun","family":"Son","sequence":"additional","affiliation":[{"name":"Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Korea"}]},{"given":"Kwang-Eun","family":"Kim","sequence":"additional","affiliation":[{"name":"Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon 34132, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"756","DOI":"10.1785\/0120180167","article-title":"Surface Deformations and Rupture Processes Associated with the 2017 Mw 5.4 Pohang, Korea, Earthquake. Bull","volume":"109","author":"Choi","year":"2019","journal-title":"Seismol. Soc. Am."},{"key":"ref_2","first-page":"65","article-title":"Coseismic liquefaction phenomenon analysis by COSMO-SkyMed: 2012 Emilia (Italy) earthquake","volume":"39","author":"Chini","year":"2015","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Gihm, Y.S., Kim, S.W., Ko, K., Choi, J.-H., Bae, H., Hong, P.S., Lee, Y., Lee, H., Jin, K., and Choi, S. (2018). Paleoseismological implications of liquefaction-induced structures caused by the 2017 Pohang earthquake. Geosci. J., 871\u2013880.","DOI":"10.1007\/s12303-018-0051-y"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"22","DOI":"10.5047\/eps.2012.11.002","article-title":"Detection and mapping of soil liquefaction in the 2011 Tohoku earthquake using SAR interferometry","volume":"64","author":"Ishitsuka","year":"2012","journal-title":"Earth Planets Space"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1080\/014311698215856","article-title":"Cover Discrimination of areas susceptible to earthquake-induced liquefaction from Landsat data","volume":"19","author":"Gupta","year":"1998","journal-title":"Int. J. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1007\/BF02989909","article-title":"Damage assessment after 2001 Gujarat earthquake using Landsat-7 satellite images","volume":"29","author":"Yusuf","year":"2001","journal-title":"J. Indian Soc. Remote Sens."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1749","DOI":"10.1080\/01431160110107824","article-title":"Satellite data reveals 26 January 2001 Kutch earthquake-induced ground changes and appearance of water bodies","volume":"23","author":"Saraf","year":"2002","journal-title":"Int. J. Remote Sens."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1581","DOI":"10.1007\/s10706-005-3811-1","article-title":"Mapping the liquefaction induced soil moisture changes using remote sensing technique: An attempt to map the earthquake induced liquefaction around Bhuj, Gujarat, India","volume":"24","author":"Ramakrishnan","year":"2006","journal-title":"Geotech. Geol. Eng."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"063531","DOI":"10.1117\/1.JRS.6.063531","article-title":"Liquefaction identification using class-based sensor independent approach based on single pixel classification after 2001 Bhuj, India earthquake","volume":"6","author":"Sengar","year":"2012","journal-title":"J. Appl. Remote Sens."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"303","DOI":"10.2113\/gseegeosci.19.4.303","article-title":"Documenting earthquake-induced liquefaction using satellite remote sensing image transformations","volume":"19","author":"Oommen","year":"2013","journal-title":"Environ. Eng. Geosci."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Zhu, J., Baise, L.G., and Koch, M. (2016, January 10\u201315). Mapping earthquake induced liquefaction surface effects from the 2011 Tohoku earthquake using satellite imagery. Proceedings of the IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Beijing, China.","DOI":"10.1109\/IGARSS.2016.7729601"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"975","DOI":"10.1193\/1.1774182","article-title":"Use of satellite SAR intensity imagery for detecting building areas damaged due to earthquakes","volume":"20","author":"Matsuoka","year":"2004","journal-title":"Earthq. Spectra"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4433","DOI":"10.1080\/01431160600675895","article-title":"Satellite radar and optical remote sensing for earthquake damage detection: Results from different case studies","volume":"27","author":"Stramondo","year":"2006","journal-title":"Int. J. Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1109\/LGRS.2012.2205661","article-title":"The 2011 Tohoku (Japan) Tsunami Inundation and Liquefaction Investigated Through Optical, Thermal, and SAR Data","volume":"10","author":"Chini","year":"2013","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_15","unstructured":"Bowers, S.A., and Hanks, R. (1971). Reflection of Radiant Energy from Soils. [Ph.D. Thesis, Kansas State University]."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1016\/S0034-4257(96)00067-3","article-title":"NDWI\u2014A normalized difference water index for remote sensing of vegetation liquid water from space","volume":"58","author":"Gao","year":"1996","journal-title":"Remote Sens. Environ."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Wang, L., and Qu, J.J. (2007). NMDI: A normalized multi-band drought index for monitoring soil and vegetation moisture with satellite remote sensing. Geophys. Res. Lett., 34.","DOI":"10.1029\/2007GL031021"},{"key":"ref_18","first-page":"1025","article-title":"Image-based atmospheric corrections-revisited and improved","volume":"62","author":"Chavez","year":"1996","journal-title":"Photogramm. Eng. Remote Sens."},{"key":"ref_19","unstructured":"Louis, J., Debaecker, V., Pflug, B., Main-Knorn, M., Bieniarz, J., Mueller-Wilm, U., Cadau, E., and Gascon, F. (2016, January 9\u201313). Sentinel-2 sen2cor: L2a processor for users. Proceedings of the Living Planet Symposium, Prague, Czech Republic."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1425","DOI":"10.1080\/01431169608948714","article-title":"The use of the Normalized Difference Water Index (NDWI) in the delineation of open water features","volume":"17","author":"McFeeters","year":"1996","journal-title":"Int. J. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"3025","DOI":"10.1080\/01431160600589179","article-title":"Modification of normalised difference water index (NDWI) to enhance open water features in remotely sensed imagery","volume":"27","author":"Xu","year":"2006","journal-title":"Int. J. Remote Sens."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/0034-4257(80)90096-6","article-title":"Remote sensing of leaf water content in the near infrared","volume":"10","author":"Tucker","year":"1980","journal-title":"Remote Sens. Environ."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1016\/S0034-4257(02)00037-8","article-title":"Designing a spectral index to estimate vegetation water content from remote sensing data: Part 1: Theoretical approach","volume":"82","author":"Ceccato","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_24","unstructured":"Chen, D., Jackson, T., Li, F., Cosh, M., Walthall, C., and Anderson, M. (2003, January 21\u201325). Estimation of vegetation water content for corn and soybeans with a normalized difference water index (NDWI) using Landsat Thematic Mapper data. Proceedings of the IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Toulouse, France."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"302","DOI":"10.1364\/JOSA.41.000302","article-title":"The near infrared absorption spectrum of liquid water","volume":"41","author":"Curcio","year":"1951","journal-title":"J. Opt. Soc. Am."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1016\/S0034-4257(98)00013-3","article-title":"Processing of high spectral resolution reflectance data for the retrieval of canopy water content information","volume":"65","author":"Rollin","year":"1998","journal-title":"Remote Sens. Environ."},{"key":"ref_27","unstructured":"Philpot, W. (2010, January 23\u201325). Spectral reflectance of wetted soils. Proceedings of the ASD and IEEE GRS, Art, Science and Applications of Reflectance Spectroscopy Symposium, Boulder, CO, USA."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"3184","DOI":"10.3390\/rs70303184","article-title":"Improvement of soil moisture retrieval from hyperspectral VNIR-SWIR data using clay content information: From laboratory to field experiments","volume":"7","author":"Baup","year":"2015","journal-title":"Remote Sens."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/18\/2184\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:22:03Z","timestamp":1760188923000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/18\/2184"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,9,19]]},"references-count":28,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2019,9]]}},"alternative-id":["rs11182184"],"URL":"https:\/\/doi.org\/10.3390\/rs11182184","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,9,19]]}}}