Use of Geological Lineaments Results in Groundwater Exploration of Crystalline Rocks, Zomba, Southern Malawi

Abstract

Locating aquifiers in Precambrian crystalline rocks offers major problems unless areas of intense weathering or fracturing are targeted. These normally occur along geological lineaments which can be identified during groundwater exploration. Major geological lineaments were identified in the Zomba area, southern Malawi, using landsat imagery and aerial photographs for groundwater exploration. In addition, areas of deep and intense fracturing identified by Very Low Frequency (VLF) geophysical technique were selected for borehole drilling. VLF results were able to locate areas with good resiststivity values which yielded borehole with water yields between 2.0 - 4.0 litres per second.

Keywords: Aquifier yields, fractured zones; Very Low Frequency(VLF) technique