Mechanism of the 2019 Yahuokou landslide reactivation in Gansu, China and its causes

In this paper, we demonstrate the estimation capabilities of landslide reactivation based on various SAR (Synthetic Aperture Radar) methods: Cloude-Pottier decomposition of Sentinel-1 dual polarimetry data, MT-InSAR (Multi-temporal Interferometric Synthetic Aperture Radar) techniques, and cloud computing of backscattering time series. The object of the study is the landslide in the east of Russia that took place on 11 December 2018 on the Bureya River. H-α-A polarimetric decomposition of C-band radar images not detected significant transformations of scattering mechanisms for the surface of the rupture, whereas L-band radar data show changes in scattering mechanisms before and after the main landslide. The assessment of ground displacements along the surface of the rupture in the 2019–2021 snowless periods was carried out using MT-InSAR methods. These displacements were 40 mm/year along the line of sight. The SBAS-InSAR results have allowed us to reveal displacements of great area in 2020 and 2021 snowless periods that were 30–40 mm/year along the line-of-sight. In general, the results obtained by MT-InSAR methods showed, on the one hand, the continuation of displacements along the surface of the rupture and on the other hand, some stabilization of the rate of landslide processes.

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Trees and Crops Arrangement in the Agroforestry System Based on Slope Units to Control Landslide Reactivation on Volcanic Foot Slopes in Java, Indonesia

Land ◽

10.3390/land9090327 ◽

2020 ◽

Vol 9 (9) ◽

pp. 327

Author(s):

Rina Purwaningsih ◽

Junun Sartohadi ◽

Muhammad Anggri Setiawan

Keyword(s):

Land Use ◽

Soil Layer ◽

Agroforestry System ◽

Rill Erosion ◽

Aerial Photo ◽

Aerial Photo Interpretation ◽

Photo Interpretation ◽

Landslide Reactivation ◽

Geomorphological Processes ◽

Controlling Processes

Agroforestry, as the dominant land use at the volcanic foot slope in Java Island, is prone to landslide due to a combination of rough relief and thick soil layer. However, evaluations of specific vegetation patterns against landslide reactivation due to soil erosion, which relays on the existing slope units and geomorphological processes, are still limited. The research data were collected through aerial photo interpretation by delineating morphological units of old landslides, slope units, and the existing land use. This was followed by field surveys for two consecutive purposes, i.e., (1) verification of aerial photo interpretation and (2) identification and intensity assessment of existing geomorphological processes. The data were tabulated according to slope units, as a basis for tree and crop arrangement in controlling erosion and landslide, by considering economic, social, and ecological functions. The agroforestry would control the landslides reactivation if the tree and crop arrangement was based on the morphological units formed by the previous landslide. The slope units are classified into residual zones at the highest elevations with flat slopes, erosion zones with the steepest slope, and sedimentation zones at the lowest elevations with gentle slopes. Trees and crops at those three units of the former landslide have different functions in controlling processes of rill erosion, gully erosion, and soil creep.

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Climate-induced landslide reactivation at the edge of the Most Basin (Czech Republic) – progress towards better landslide prediction

Natural Hazards and Earth System Science ◽

10.5194/nhess-13-361-2013 ◽

2013 ◽

Vol 13 (2) ◽

pp. 361-374 ◽

Cited By ~ 10

Author(s):

J. Burda ◽

F. Hartvich ◽

J. Valenta ◽

V. Smítka ◽

J. Rybář

Keyword(s):

Water Table ◽

Laser Scanning ◽

Shear Plane ◽

Morphological Development ◽

Climatic Data ◽

Landslide Activity ◽

Geomorphological Mapping ◽

Reactivated Landslide ◽

Dramatic Rise ◽

Landslide Reactivation

Abstract. The catastrophic landslide at Eisenberg in North Bohemia was reactivated during January 2011. This study integrates a range of geoscientific evidence in order to constrain the spatial and temporal development of this reactivation. It has investigated long-term geodetic measurements to assess the morphological development of the site over the last two decades. There is evidence to suggest that, over this period, the site had been subjected to progressive deformation caused by the collapse of an old mine gallery. However, climatic data show that the reactivation itself was triggered by a dramatic rise in the water table induced by rapid snowmelt during a period of winter warming. Furthermore, geomorphological mapping has been used to characterise the morphology of the reactivated landslide and geophysical profiling has been used to analyse its internal structure. The results show that fissures are continuing to develop above the reactivated landslide scarp while highly saturated stiff-fissured claystones provide an incipient slide plane. The application of laser scanning has shown minimal evidence for ongoing landslide activity. It is, however, clear that future landslide events will occur here due to the favourable lithological, structural, and geotechnical conditions. Finally, we propose that future landslide activity at the site may be predicted by the height of water table as this defines theoretical pore pressure at the depth of the shear plane.

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