Comparing Electrical and Magnetic Properties of Soil Layer from Sag Pond near Lembang Fault, West Java, Indonesia

Abstract

Electrical and magnetic properties have been used in soil characterization for various types of soils except for soil originated from sag pond sediment. Formed near fault line, sag pond provides a unique environment for sedimentation. In this study, electrical conductivity and magnetic susceptibility of soil samples obtained by coring process were measured to find out how these two properties were related. A 364 cm core was obtained in a sag pond located next to Lembang Fault in West Java, Indonesia. The core covers two different layers that are differ not only on their coloration and texture but also showed variations in their electrical conductivity and magnetic susceptibility. In the first layer, termed silty loam (above 165 cm), electrical conductivity correlates positively with magnetic susceptibility whereas in the second layer, termed silty-clay (below 165 cm) the correlation is negative. These differences are probably due content of magnetic minerals that is high in silt but low in clay. The results of this study infer that correlation between electrical conductivity and magnetic susceptibility could then be used as a tool to delineate soil layers.