The lack of access to potable water in Kitui has resulted to famine and high infant mortality rates, which has risen to 9.8% and life expectancy is declining steadily. The fact that the basement system is hard Precambrian rock, ground water tends to be more localized and thus sustainable wells cannot be dug on a trial and error basis. The aim of this project was to evaluate groundwater potential located in the concealed fractured /faulted zones which act as groundwater storage and conduits, using magnetic and geo-electrical geophysical techniques. A terrameter was used to collect resistivity data and subsequently determine the subsurface layer resistivity anomalies using Wenner profiling and resistivity sounding inversion software, IP2WIN. Proton precession magnetometer was used to measure the total magnetic field intensity of the earth and 2D Euler deconvolution software was used to model the disintegrated basement. Magnetic surveys showed distinct magnetic anomalies signifying disruption of the basement rock which occur due to faulting. Resistivity surveys also showed low resistivity anomaly at points of significant magnetic anomaly. This suggests groundwater potential in the inferred fault.

Forward modelling of gravity and magnetic data was done simultaneously to show the correlation between gravity and magnetic anomalies on a measured heat flux region. The results were used to characterize the heat source structures in Eburru area. Modelling was done using Oasis montaj geosoft software which is an iteration process where the gravity and magnetic anomalies were calculated and compared to the observed residual anomaly until there was a fit. The start model was constructed based on depths from Euler deconvolution and models constrained using stratigraphy data from the existing wells in the study area. Forward modelling of gravity and magnetic data revealed intrusions within the Earth's subsurface with depth to the top of the sources ranging from 739 m to 5811 m. The density of the sources ranges between 3.0 g/cm 3 and 3.2 g/cm 3 while their magnetic susceptibility was zero. This implies that intrusions from the mantle with a magnetic susceptibility of zero have temperatures exceeding the curie temperature of rocks. The density of the intrusions modelled was higher than 2.67 g/cm 3 , the average crustal density, hence it explains the observed positive gravity anomaly. The results also revealed that areas with high heat flux have shallow heat sources and if the heat sources are deep, then there must be a good heat transfer mechanism to the surface.