{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T20:49:32Z","timestamp":1768682972276,"version":"3.49.0"},"reference-count":42,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2009,1,21]],"date-time":"2009-01-21T00:00:00Z","timestamp":1232496000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Slope instabilities are one of the most important geo-hazards in terms of socio-economic costs. The island of La R\u00e9union (Indian Ocean) is affected by constant slope movements and huge landslides due to a combination of rough topography, wet tropical climate and its specific geological context. We show that remote sensing techniques (Differential SAR Interferometry and correlation of optical images) provide complementary means to characterize landslides on a regional scale. The vegetation cover generally hampers the analysis of C\u2013band interferograms. We used JERS-1 images to show that the L-band can be used to overcome the loss of coherence observed in Radarsat C-band interferograms. Image correlation was applied to optical airborne and SPOT 5 sensors images. The two techniques were applied to a landslide near the town of Hellbourg in order to assess their performance for detecting and quantifying the ground motion associated to this landslide. They allowed the mapping of the unstable areas. Ground displacement of about 0.5 m yr-1 was measured.<\/jats:p>","DOI":"10.3390\/s90100616","type":"journal-article","created":{"date-parts":[[2009,1,21]],"date-time":"2009-01-21T10:53:12Z","timestamp":1232535192000},"page":"616-630","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Observation of a Large Landslide on La Reunion Island Using Differential Sar Interferometry (JERS and Radarsat) and Correlation of Optical (Spot5 and Aerial) Images"],"prefix":"10.3390","volume":"9","author":[{"given":"Christophe","family":"Delacourt","sequence":"first","affiliation":[{"name":"Universit\u00e9 Europ\u00e9enne de Bretagne, Universit\u00e9 de Brest; CNRS; UMR 6538 Domaines Oc\u00e9aniques; Institut Universitaire Europ\u00e9en de la Mer, Place Copernic, 29280 Plouzan\u00e9, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Raucoules","sequence":"additional","affiliation":[{"name":"BRGM, Am\u00e9nagement et Risque Naturels, 3 avenue Claude Guillemin, 45060 Orl\u00e9ans cedex 2, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"St\u00e9phane","family":"Le Mou\u00e9lic","sequence":"additional","affiliation":[{"name":"Laboratoire de Plan\u00e9tologie et G\u00e9odynamique, CNRS\/UMR 6112, Universit\u00e9 de Nantes, 2 rue de la Houssini\u00e8re, 44322 Nantes cedex, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudie","family":"Carnec","sequence":"additional","affiliation":[{"name":"BRGM, Am\u00e9nagement et Risque Naturels, 3 avenue Claude Guillemin, 45060 Orl\u00e9ans cedex 2, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Denis","family":"Feurer","sequence":"additional","affiliation":[{"name":"BRGM, Am\u00e9nagement et Risque Naturels, 3 avenue Claude Guillemin, 45060 Orl\u00e9ans cedex 2, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pascal","family":"Allemand","sequence":"additional","affiliation":[{"name":"Laboratoire Sciences de la Terre \u2013 UCBL&ENS-UMR 5570 CNRS Bat G\u00e9ode 2 Rue Dubois 69622 Villeurbanne Cedex, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marc","family":"Cruchet","sequence":"additional","affiliation":[{"name":"BRGM, Am\u00e9nagement et Risque Naturels, 3 avenue Claude Guillemin, 45060 Orl\u00e9ans cedex 2, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2009,1,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"446","DOI":"10.1111\/j.1744-7429.2006.00178.x","article-title":"Landslides and their contribution to land-cover in the mountains of Mexico and Central America","volume":"38","author":"Restrepo","year":"2006","journal-title":"Biotropica"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1078\/1433-8319-00042","article-title":"Tropical forest recovery: legacies of human impact and natural disturbances. Perspectives","volume":"6","author":"Chazdon","year":"2003","journal-title":"Plant Ecol. Evolution. Syst."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/S0013-7952(01)00093-X","article-title":"Landslide risk assessment and management: an overview","volume":"64","author":"Dai","year":"2002","journal-title":"Engineering Geology."},{"key":"ref_4","unstructured":"Cruchet, M. (1994). Rapport BRGM\/RR-37962-FR."},{"key":"ref_5","unstructured":"Faye, J., and Lakhdar, Y. (2000). Dossier d'information du Minist\u00e8re de l'Am\u00e9nagement du Territoire et de l'Environnement."},{"key":"ref_6","unstructured":"Cruchet, M. (2000). Rapport BRGM\/RP\u201350112\u2013FR."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/S0013-7952(99)00122-2","article-title":"A critical review of landslide monitoring experiences","volume":"55","author":"Angeli","year":"2000","journal-title":"Eng. Geol."},{"key":"ref_8","first-page":"93","article-title":"Measurement of local horizontal velocities on the Slumgullion landslide using the Global Positioning System","volume":"2130","author":"Jackson","year":"1996","journal-title":"U.S. Geol. Surv. Bull."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/S0169-555X(01)00098-8","article-title":"The use of Global Positioning System techniques for the continuous monitoring of landslides","volume":"43","author":"Malet","year":"2002","journal-title":"Geomorphology"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1016\/j.enggeo.2005.01.015","article-title":"Differential single-frequency GPS monitoring of the La Valette landslide (French Alps)","volume":"79","author":"Squarzoni","year":"2005","journal-title":"Eng. Geol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1016\/S0040-1951(96)00047-9","article-title":"Observation and modelling of the Saint-Etienne-de-Tin\u00e9e landslide using SAR interferometry","volume":"265","author":"Fruneau","year":"1996","journal-title":"Tectonophysics"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"3579","DOI":"10.1029\/96GL03042","article-title":"Two examples of the use of SAR interferometry on displacement fields of small spatial extension","volume":"23","author":"Carnec","year":"1996","journal-title":"Geophys. Res. Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/S0013-7952(02)00198-9","article-title":"Nine years of spatial and temporal evolution of the \u201cLa Valette\u201d landslide observed by SAR interferometry","volume":"68","author":"Squarzoni","year":"2003","journal-title":"Eng. Geol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1702","DOI":"10.1109\/TGRS.2003.813273","article-title":"JERS SAR interferometry for land subsidence monitoring","volume":"41","author":"Strozzi","year":"2003","journal-title":"IEEE. Trans. Geosci. Remote Sens."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"527","DOI":"10.5194\/nhess-5-527-2005","article-title":"Remote sensing of glacier- and permafrost-related hazards in high mountains: An overview","volume":"5","author":"Huggel","year":"2005","journal-title":"Nat. Haz. Earth Syst. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1029\/2004GL020193","article-title":"Velocity field of the \u201cLa Clapi\u00e8re\u201d landslide measured by the correlation of aerial and QuickBird images","volume":"31","author":"Delacourt","year":"2004","journal-title":"Geophys. Res. Lett."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"89","DOI":"10.2113\/gssgfbull.178.2.89","article-title":"Remote-sensing techniques for analysing landslide kinematics: a review","volume":"178","author":"Delacourt","year":"2007","journal-title":"Bull.Soc. G\u00e9olog. France"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"425","DOI":"10.5194\/nhess-5-425-2005","article-title":"Contribution of multi-temporal remote sensing images to characterize landslide slip surface \u2013 Application to the La Clapi\u00e8re landslide (France)","volume":"5","author":"Casson","year":"2005","journal-title":"Nat. Haz. Earth Syst. Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1111\/j.1365-246X.2008.03743.x","article-title":"Measuring coseismic deformation on the northern segment of the Bam Baravat escarpment associated with the 2003 Bam (Iran) earthquake, by correlation of very-high-resolution satellite imagery","volume":"173","author":"Raucoules","year":"2008","journal-title":"Geophys. J. Int."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"950","DOI":"10.1109\/36.175330","article-title":"Decorrelation in interferometric radar echoes","volume":"30","author":"Zebker","year":"1992","journal-title":"IEEE. Trans. Geosci. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1029\/97RG03139","article-title":"Radar interferometry and its application to changes in the earth's surface","volume":"4","author":"Massonnet","year":"1998","journal-title":"Rev. Geophys."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1038\/364138a0","article-title":"The displacement field of the Landers earthquake mapped by radar interferometry","volume":"364","author":"Massonnet","year":"1993","journal-title":"Nature"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"4035","DOI":"10.1029\/1998GL900033","article-title":"Radar Interferogram filtering for geophysical applications","volume":"25","author":"Goldstein","year":"1998","journal-title":"Geophys. Res. Lett."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1038\/375567a0","article-title":"Deflation of Mount Etna monitored by spaceborn radar interferometry","volume":"375","author":"Massonnet","year":"1995","journal-title":"Nature"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/S0926-9851(99)00032-4","article-title":"Three years of mining subsidence monitored by SAR Interferometry, near Gardanne, France","volume":"43","author":"Carnec","year":"2000","journal-title":"Appl. Geophys."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1016\/j.crte.2007.02.002","article-title":"Use of SAR interferometry for detecting and assessing ground subsidence","volume":"339","author":"Raucoules","year":"2007","journal-title":"Compt. Rend. Geosci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"27051","DOI":"10.1029\/98JB02794","article-title":"Integrated satellite interferometry: tropospheric noise, GPS estimates and implications for interferometric synthethic aperture products","volume":"103","author":"Williams","year":"1998","journal-title":"J. Geophys. Res."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"989","DOI":"10.1029\/96GL00622","article-title":"Atmospheric propagation heterogeneities revealed by ERS-1 interferometry","volume":"23","author":"Tarayre","year":"1998","journal-title":"Geophys. Res. Lett."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2849","DOI":"10.1029\/98GL02112","article-title":"Tropospheric corrections of SAR interferograms with strong topography: Application to Etna","volume":"25","author":"Delacourt","year":"1998","journal-title":"Geophys. Res. Letters."},{"key":"ref_30","unstructured":"Strozzi, T., K\u00e4\u00e4b, A., Frauenfelder, R., and Wegm\u00fcller, U. (2003, January July). Detection and Monitoring of Unstable High-Mountain Slopes with L-Band SAR Interferometry. Toulouse, France."},{"key":"ref_31","unstructured":"Wilson, A. (2001, January September). Feasibility of DINSAR for mapping complex motion fields of Alpine ice and rock glaciers. Sheffield, UK."},{"key":"ref_32","unstructured":"Werner, C.L., Wegmuller, U., Strozzi, T., and Wiesmann, A. (2000, January October). GAMMA SAR and interferometric processing software. Gothenburg, Sweden."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"468","DOI":"10.1016\/j.rse.2003.09.005","article-title":"Monitoring of slow ground deformation by ERS radar interferometry - The case of Vauvert (France)","volume":"88","author":"Raucoules","year":"2003","journal-title":"Remote Sens. Environ."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Durand, P., Sigmundsson, F., and Massonnet, D. Opening of the March 1998 eruptive fissure at Piton de la Fournaise volcano measured by RADARSAT satellite radar interferometry.","DOI":"10.1029\/1999GL900055"},{"key":"ref_35","unstructured":"Vadon, H., and Massonnet, D. (, January July). Earthquake displacement fields mapped by very precise correlation. Complementarity with radar interferometry. New York, USA."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"3486","DOI":"10.1364\/AO.39.003486","article-title":"Measuring earthquakes from optical satellite images","volume":"39","author":"Michel","year":"2000","journal-title":"Appl. Optic."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"2062","DOI":"10.1029\/2000JB000102","article-title":"Deformation due to the 17 August 1999 Izmit, Turkey, earthquake measured from SPOT images","volume":"107","author":"Michel","year":"2002","journal-title":"J. Geophys. Res."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"L02307","DOI":"10.1029\/2004GL021897","article-title":"Horizontal coseismic deformation of the 2003 Bam (Iran) earthquake measured from SPOT-5 THR satellite imagery","volume":"32","author":"Binet","year":"2005","journal-title":"Geophys. Res. Lett."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/S0924-2716(02)00114-4","article-title":"Monitoring high-mountain terrain deformation from repeated air- and spaceborne optical data: examples using digital aerial imagery and ASTER data","volume":"57","author":"Kaab","year":"2002","journal-title":"ISPRS J. Photogram. Remote Sens."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.rse.2004.11.005","article-title":"Mountain glaciers surface motion derived from satellite optical imagery","volume":"95","author":"Berthier","year":"2005","journal-title":"Remote Sens. Environ."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1111\/j.1365-246X.2006.03307.x","article-title":"Deformation between 1989 and 1997 at Piton de la Fournaise volcano retrieved from correlation of panchromatic airborne images","volume":"169","author":"Briole","year":"2007","journal-title":"Geophys. J. Int."},{"key":"ref_42","unstructured":"Vadon, H., and Massonnet, P. Earthquake displacement fields mapped by very precise correlation. Complementarity with radar interferometry. New Jersey."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/9\/1\/616\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:09:44Z","timestamp":1760220584000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/9\/1\/616"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,1,21]]},"references-count":42,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2009,1]]}},"alternative-id":["s90100616"],"URL":"https:\/\/doi.org\/10.3390\/s90100616","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,1,21]]}}}