Integrated Geophysical Analysis for Landslide Risk Mitigation: A Case Study on the Weak Zone Area of Jantho-Lamno Route, Aceh, Indonesia

Abstract

A study was conducted along the Jantho-Lamno road to identify and mitigate landslide risks by analyzing the relationship between seismic wave propagation velocity and rock resistivity. The research aimed to assess geological conditions and pinpoint areas prone to slope failure, employing both seismic and resistivity methods on three selected lines (L1, L2, L3). Seismic wave propagation velocity (Vp) and resistivity (ρ) values were analyzed using ZondST2D and Res2Dinv software. The results revealed a distinct weak zone characterized by contrasting layers: a soft first layer and a denser second layer. Within this zone, Vp ranged from 0.3 to 0.9 km/s, with resistivity measuring less than 10 Ωm, mainly comprising sandstone and clay. This weak zone acted as a slip plane, driven by a water-saturated layer's pushing force, making it susceptible to structural instability due to gravitational pressure. To mitigate land creep, the proposed strategy involved constructing retaining walls, piles, shotcrete, wire mesh, net rock bolting, and rock removal techniques, tailored to the geological conditions of L2 and L3 Jantho. Similar measures would be implemented at L1 Lamno. L1 Lamno was identified as an ideal location for studying slope stability mitigation measures. Landslides in Aceh Province result from factors such as active tectonic movements, intense rainfall, geological structures, weathering processes, and seismic activity. Implementing slope stabilization and protection methods effectively reduces landslide risks, benefiting the region's safety and infrastructure.