Acta Geodynamica et Geomaterialia

Title: INTEGRATED ANALYSIS OF GEOPHYSICAL METHODS FOR LANDSLIDE CHARACTERIZATION
Authors: Zakaria Muhammad Taqiuddin, Muztaza Nordiana Mohd and Ismail Nur Azwin
DOI: 10.13168/AGG.2023.0015
Journal: Acta Geodynamica et Geomaterialia, Vol. 20, No. 4 (212), Prague 2023
Full Text: PDF file (1.9 MB)
Keywords: resistivity, seismic refraction, landslide
Abstract: Landslides are often regarded as secondary hazards, typically triggered by major catastrophic events like storms, floods, volcanic eruptions, and earthquakes. In tropical regions such as Malaysia, the prevalent geohazard phenomenon involves landslides induced by moisture or rainfall. These incidents predominantly occur due to the unique composition of residual soils in the area, resulting from the weathering of bedrock in situ. Major landslides and local slope failures occur when water saturation exceeds a critical limit in certain parts of the slope. The foundation of a dependable stability analysis lies in the geological model of the landslide, which should accurately reflect the actual conditions. To achieve this, a thorough understanding of the landslide phenomenon and access to high-quality datasets are essential. In this study, 2D electrical resistivity imaging and seismic refraction tomography were utilized to identify subsurface characteristics, along with geotechnical data for data corroboration. The study shows a highly weathered zone (ρ< 1200 Ωm; Vp< 1200 m/s) was identified at a depth of less than 5 m. The number of blows (N-values) for standard penetration test (SPT) indicate a low range of 1–15, representing the low stiffness of the soil condition. The N-values show variation in the number of blows with depth, suggesting that the layer may not be competent due to the present heterogeneous material caused by the highly weathered process. The results emphasize the benefits of incorporating both geophysical and geotechnical parameters to define subsurface properties. The study offers insights into how spatial distributions of these parameters can be utilized to minimize uncertainty in ground models.