The Wenner configuration of geoelectrical method to identify landslide areas on protocol street (case study: Jl. Raya Kambal – Mulyorejo, Ngantang, Malang)

This research investigated the alleged existence of potential landslides in front of the Kambal-Mulyorejo Highway section Ngantang District Malang Regency. The purposes of this research determined the subsurface geological structure in front of Highway Kambal – Mulyorejo, Ngantang subdistrict of Malang Regency, and to find out the potential landslides in this area. This research utilizes the Wenner configuration of the geoelectric resistivity method. Measurement was taken in 3 tracks with two tracks in the vertical direction and one track in the horizontal direction. Every track has 200 m with a space of electrode 10 m. Transition resistivity values use Res2dinV software that can provide 2D information from the color that can explain values from each layer resistivity. The three layers have one thing in common, namely the presence of a clay layer with a range of resistivity values of 1.74– 26.1 Ωm. Suspected on the first and third track, there is a slip plane. Because it was found that there's a layer that easily absorbs water but doesn't escape the water, so it will easily collapse when on a slope. In addition, this layer also follows the slope, so it was thought to be a slip plane. Meanwhile, in the second track, it was suspected that slip planes in there, this occurs because the waterproof layer tends to be flat and not tilted following the slope.