2-D Cross-Plot Model Analysis Using Integrated Geophysical Methods for Landslides Assessment

Abstract

The large or small scale of a landslide is a natural, widespread process, resulting from the downward and outward movement of slope-forming materials, such as sculpting the landscape. Characterized landslide material and properties’ inhomogeneities conditions become a challenge as the process required the availability of a wide range of data, observations, and measurements with an evaluation of geological and hydrological conditions. Detailed investigations represent an essential component of the landslide risk mitigation process, relying on subsurface investigations, discrete subsurface sampling, and laboratory tests. To extend this approach, seismic refraction and two-dimensional (2-D) resistivity were utilized to study the landslides activities in Ulu Yam. The cross-plot analysis was introduced to integrate the geophysical results based on the criteria of the model. Velocity distributions from seismic refraction revealed the stiffness of the soil, where weak zones identified with values of Vp ≤ 1200 m/s, defined as threshold frequency for failure to occur. The 2-D resistivity shows that the weak zones were identified with resistivity values of <1200 Ωm. The 2-D cross-plot model gives a comprehensive interpretation where a low velocity and resistivity value represents the failure plane of materials to failure. The volume of mass sliding was calculated based on retrieved information from the model.

Keywords

• 2-D resistivity
• seismic refraction
• rainfall-landslide
• geophysics
• environmental engineering