APPLICATION OF ELECTRICAL RESISTIVITY TOMOGRAPHY FOR DETECTING DIAPIR STRUCTURES IN MUD VOLCANO ZONES

Abstract

This article discusses the use of Electrical Resistivity Tomography (ERT) to analyze the diapir structure underneath the Ciuyah mud volcano zone in Kuningan, West Java. A mud volcano is a natural occurrence where fluid and gas materials are forced to the surface due to intense pressure beneath the surface, particularly during diapir formation. Mud volcano phenomena are commonly linked to structures such as faults or fractures caused by tectonic activity, providing pathways for mud to emerge. This study aimed to determine the geological structure and lithology of the layers in the area by analyzing the distribution of resistivity values. The method employed was electrical resistivity tomography (ERT), which involves passing direct current into the rocks. Physical properties of the rocks, such as current and potential difference, were measured, and the apparent resistivity was calculated. The ERT measurements revealed variations in resistivity values. The upper layer, composed of sand mixed with mud volcano eruption products, exhibited a resistivity of 1.0 – 3 Ωm, while the underlying calcareous clay layer had a resistivity of 5 – 60 Ωm. Furthermore, the ERT cross-section indicated a discontinuity pattern in the layers, potentially indicative of the presence of a fault structure oriented east-southeast to west-northwest (ESE-WNW) and a folding pattern in the form of a syncline with compression directed to the northeast. Other structures identified included a salt diapir, suspected to contribute to the migration of mud and saline water to the surface