Earthflow reactivation assessment by multichannel analysis of surface waves and electrical resistivity tomography: A case study

Open Geosciences

Iqbal Ibrar¹  Abdelrahman Kamal²  Alzahrani Hassan²  Badran Osman M.³  El-Raouf Amr Abd⁴  Meister Julia⁵ 

[1] College of Geosciences, Guilin University of Technology, Guilin, 541004, Guangxi, China;Department of Geology and Geophysics, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia;Geology Department, Faculty of Science, Damanhour University, El-Gomhouria St, Damanhour 22511, Egypt;Geology Department, Faculty of Science, Zagazig University, Zagazig 44519, Egypt;Institute of Geography and Geology, Chair of Physical Geography, University of Würzburg, Am Hubland, 97074 Würzburg, Germany;

关键词: earthflow;    geophysical approach;    electrical resistivity tomography;    pseudo-3d survey;    multichannel analysis of surface waves;    noninvasive;   

DOI  :  10.1515/geo-2020-0310

来源: DOAJ

【 摘 要 】

In this study, we investigated the stability and reactivation of preexisting Tonghua landslide deposits in China, including the adjacent stable slope. We used an integrated approach, combining a multichannel analysis of surface waves (MASW) and electrical resistivity tomography (ERT). We used ERT to determine groundwater seepage paths, weathering conditions, water content, and the depth to bedrock. High-resolution two-dimensional (2D) shear-wave velocity MASW images, on the other hand, played an essential role in detecting both horizontal and vertical compositions, disjointedness, and sliding surfaces related to lithological borders. Based on seismic models, we considered four geological layers encountered in the stable slope, including fractured (gravel) and weathered (phyllite) materials, as a sliding mass. We combined the 2D resistivity profiles obtained to create pseudo-three-dimensional ERT images to estimate water-saturated and unsaturated masses. From the tomography results, we identified different preexisting deposits, including buried arable clay deposits, old accumulated earthflow deposits, a water accumulation zone, and a fissure runoff. Based on the resistivity results, the bottom of the earthflow deposits is susceptible to water, and oversaturation can reactivate the earthflow.

【 授权许可】

Unknown