Geophysical investigation for groundwater exploration at UKM's Kuala Pilah Matriculation Centre, Negeri Sembilan

Abstract

A geophysical investigation was conducted at the UKM's matriculation centre in Kuala Pilah, Negeri Sembilan by the Department of Geology, Universiti Kebangsaan Malaysia. The study was initiated as a result of water shortage in the area. The normal supply of piped water by Jabatan Bekalan Air (JBA) is either insufficient or totally cut off for several days especially during dry season. The aim of the study was to look for groundwater as a possible source of back up water supply for the centre. Geoelectrical resistivity sounding and seismic methods were adopted for assessment of the groundwater potential of the site and to determine the subsurface conditions of the area. A total of eleven sounding stations and eight seismic profiles were established. A layer of low resistivity « 100 ohm-m) was detected at eight sounding localities within the study area. This conductive layer could be associated with a near surface water saturated zone or aquifer. However based on seismic data and by taking velocity of 1,600 to 1,700 mls for the water saturated zone, only one location (S4ISP3) was found to be favourable. The potential water saturated layer has a resistivity value and a seismic velocity of about 80 ohm-m and 1,690 mls respectively. Both geoelectrical and seismic results show good agreement in term of depth below surface (- 2 metres) and layer thickness (- 30 metres). However, these results need to be confirmed by drilling.