Analysis of Subsurface Resistivity Distribution of the Kelud Volcano Using Magnetotelluric Method

Abstract

Indonesia has the world’s most active volcanoes, with more than 30% of them lying within its borders. The Kelud volcano erupted in 2007, resulting in the development of a Lava Dome in the crater lake. This phenomena is known as effusive. The magnetotelluric approach is used in this study to predict the subsurface resistivity distribution in the Kelud volcano area. Data was obtained at 10 different locations around the Kelud volcano area. The subsurface structure of the Kelud Volcano can be identified based on resistivity values that show significant differences, according to the modelling results. According to the findings, the surface resistivity surrounding the Kelud volcano ranges from 1 to 100 ohm. The main structure of the hydrothermal system’s clay cap was discovered at a depth of 1000 m from the surface in the western part of the summit, with resistivity values ranging from 1-10.m. With a resistivity of more than 100 ohm.m., a high resistivity forming a conduit appears in the centre of the summit area. The subsurface structure values obtained indicate that these structures are volcanic.