Remote Sensing for Characterisation and Kinematic Analysis of Large Slope Failures: Debre Sina Landslide, Main Ethiopian Rift Escarpment

Remote Sensing

Ivo Baroň¹  Joachim Eberle²  Volker Hochschild²  Jan Kropáček²  Atanu Bhattacharya³  Zuzana Vařilová⁴ 

[1] Department of Geology and Paleontology, Natural History Museum Vienna, Burgring 7, 1010 Vienna, Austria;Department of Geosciences, University of Tuebingen, Rümelinstr. 19–23, 72070 Tübingen, Germany;Institute for Cartography, TU Dresden, Helmholzstr. 10, 01062 Dresden, Germany;Municipal Museum of Ústí nad Labem, Masarykova 1000/3, 400 01 Ústí nad Labem, Czech Republic;

关键词: Ethiopian rift;    Tarmaber area;    Debre Sina;    large landslide;    feature tracking;    amplitude tracking;    DEM differencing;    ICESat;   

DOI  :  10.3390/rs71215821

来源: DOAJ

【 摘 要 】

Frequently occurring landslides in Ethiopia endanger rapidly expanding settlements and infrastructure. We investigated a large landslide on the western escarpment of the Main Ethiopian Rift close to Debre Sina. To understand the extent and amplitude of the movements, we derived vectors of horizontal displacements by feature matching of very high resolution satellite images (VHR). The major movements occurred in two phases, after the rainy seasons in 2005 and 2006 reaching magnitudes of 48 ± 10.1 m and 114 ± 7.2 m, respectively. The results for the first phase were supported by amplitude tracking using two Envisat/ASAR scenes from the 31 July 2004 and the 29 October 2005. Surface changes in vertical direction were analyzed by subtraction of a pre-event digital elevation model (DEM) from aerial photographs and post-event DEM from ALOS/PRISM triplet data. Furthermore, we derived elevation changes using satellite laser altimetry measurement acquired by the ICESat satellite. These analyses allowed us to delineate the main landslide, which covers an area of 6.5 km2, shallow landslides surrounding the main landslide body that increased the area to 8.5 km2, and the stable area in the lower part of the slope. We assume that the main triggering factor for such a large landslide was precipitation cumulated over several months and we suspect that the slope failure will progress towards the foot of the slope.

【 授权许可】

Unknown