RESISTANCE ANALYSIS OF ROCK AND MINERAL UNDER SURFACE BY USING GEOELECTRIC METHOD IN THE VILLAGE OF DOLOK MARAWA SIMALUNGUN DISTRICT

We have conducted the research to analyze the resistivity of rocks and minerals under the surface in the area Dolok Marawa Simalungun District. This research aims to determine the types of rocks and minerals under the surface based on the value of resistivity in the village of Dolok Marawa Simalungun Distrik. Determining the type of rocks and minerals under the surface by using geoelectric method were performed using an ARES geoelectric (Automatic Resistivity System) Schulumberger configuration three path tand length of path is 155 meter. Resistivity value of rocks and minerals below the surface is processed by using software Res2Dinv to obtain two dimensional cross-section. Research results obtained show that the geoelectric resistivity varies in the range of 0.327 Ωm which is groundwater up to 2200 Ωm which is a limestone. Type of Under surface mineral Dolok Marawa Village was the most dominating ground water with a resistivity value of less than 10 Ωm and predicted that in this research area is still ongoing volcanic activity. The rocks that make up the area is still ongoing volcanic activity. The rocks that make up the area are thought to be clay, silt, andesite, alluvium, sandstone and limestone.