Investigation of Groundwater Potential Based On Vertical Electrical Sounding Methode On Gosoma District In North Halmahera

Abstract

Population growth has encourage an increasing of clean water needs as a basic human necessity, both in terms of quality and quantity. River water and rain water are sources of raw materials for these elementary needs, however global climate change has indirectly affected the hydrological characteristics of the last few decades. Thus, the use of ground water is a solution in meeting these needs. The research aims to identify the potential presence of ground water that can be used as a source of fresh water in the village of Gosoma, Tobelo, North Halmahera Regency. This potential fresh water investigation was carried out using a Mc Ohm Mark-2 OYO resistivity meter, while the Schlumberger configuration was the measurement method used. The length of the track geoelectric extends as far as 1,060 m, while for transverse profiles as far as 560 with a total number of measurement points of 6 points. The results of geoelectric measurements show that there are 2 layers that have the potential as deep aquifers. First groundwater layers predicted at a depth that varies between 21.10 m - 83.00 m and secondary groundwater layer may exist deeper than 95.90 m above the surface. This result were indicated by resistivity values measured at the observed points, where the values varies from 18.10 ohms to 91.30 ohms. Those resistivity value illustrates that lithology of the soil layer were indicated as a layer of sand and sandy tuff, where both of the rock lithologies layer have a potential as a layer of ground water.