Natural disaster mitigation using geophysical methods

Abstract

The research has been carried out about natural disasters (landslides, ground motion, drought) using geophysical methods. This research was conducted in several places, in East Java, i.e. land slides and ground motion occurred in Malang and Blitar areas and drought occurred in theTulungagung and Malang areas. This research uses resistivity and self-potential. The active method is resistivity, which means that an electric current is injected into the earth, after which the resulting potential difference is recorded, then processed. Self-potential and geomagnetic methods, are passive methods. In the self-potential method, the potential difference that occurs between two points, which have a certain distance, is recorded (the middle between those two points becomes a point measurement). The data of several points of measurement, that have been made within a certain distance, then is processed for determining underground river tracing. The equipment used is the OYO Mac Ohm resistivity meter. The results obtained are, an artesian well in the Tulungagung area, at a depth of 108 m, an indication of new faults in the Blitar area, and ground motion cracks in the Malang area.