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SPACE BORNE RADAR INTERFEROMETRIC MAPPING OF PRECURSORY DEFORMATIONS OF A DYKE COLLAPSE, DEAD SEA, JORDAN. Closson, Abou Karaki, al-Fugha dclosson@mail.com naj@paris.com. Ikonos : 19-10-2000. The case study : the collapse of the salt evaporation pond 19 of the Arab poatsh Company. 1650m.
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SPACE BORNE RADAR INTERFEROMETRIC MAPPING OF PRECURSORY DEFORMATIONS OF A DYKE COLLAPSE, DEAD SEA, JORDAN Closson, Abou Karaki, al-Fugha dclosson@mail.com naj@paris.com
Ikonos : 19-10-2000 The case study : the collapse of the salt evaporation pond 19 of the Arab poatsh Company 1650m
The SEP costed 32 M Jordan Dinar It collapsed on March 22, 2000 55 M m3 brine to the Dead Sea in less than one our
After the mid sixties The Dead Sea Decrease from -392m To -418m
1961-1962 1993 1999 June, 30 1993 ERS Radar Images May, 29 1999 Lisan Coastline
Remote sensing SAR • SAR = Synthetic Aperture RADAR (RAdio Detection And Ranging) • SAR is a sensor able to generate high resolution images • imaging sensor: • Allows the observation of the Earth surface in 2D • exemple of another sensor : • Radar altimetre: provide data in one dimension. Allow generation of topographic maps
SAR remote sensing - properties • main characteristics of SAR images: • 1. It is an active system (illuminate the area of interest with microwaves) • independant of solar illumination • allows measurement in day and night conditions • 2. use micro-waves to penetrate through cloud cover • allows observations in cloud cover areas • remark: it alters the accuracy of measurements • 3. Its a coherent system by opposition to visible remote sensing wich • use the incoherent light of the sun • allows the use of interferometry technic
SAR remote sensing - properties • 4. SAR allows the observation of Earth surface properties that are not accessible to visible sensors • - rugosity, dielectric properties (through coherence images) • - possibilities to penetrate • - the vegetation (L band) • - ultra dry soil • - snow cap • 5. The Sar resolution is independant of the distance between the sensor • and the objective • 6. – Allows the utilisation of different polarization in transmission as well as • in reception : • HH, HV, VV, VH • - Allows the utilization of different frequencies
SAR applications • 1. Geometric applications, based on the interferometric phase: • - Generation of digital terrain model (DTM) • Technic: SAR interferometry (InSAR) - Control the deformations fields over the Earth surface • Technic:differential SAR interferometry (DInSAR) • 2. Thematic application • - Change detection from coherence variation through time (soil erosion, flood)
M S P P’ Deformation fields : principle
DInSAR Topo topographic phase Mov movement Atm atmosphere Noise noise of instruments The differential interferometric phase is a sum of several components