Application of Geoelectrical Resistivity Methods for Mapping of Seawater Intrusion

Abstract

Excessive land exploitation in Dumai has been replaced by intrusion seawater in aquifers in the coastal area. This is indicated by the increasing number of society's wells that turn into brackish. The intrusion has a wide impact on various aspects of life, such as decreasing soil fertility, damage the buildings, and disrupting public health. The aim of this study is to find out the saturated zone of water and the interface of water with fresh water, so it is known that water zones are suitable for daily use. The study used Geoelectrical Resistivity Survey with 1D Schlumberger configuration to determine the zone of aquifer and its thickness. Based on the research that has been done, the results of the boundary of the intrusion zone in Dumai were obtained that there is an intrusion zone boundary of seawater content. This is indicated by the low resistivity value. It is less than 10 ohms, which is found at the zone of less than 1 km from the beach line.