Asian Journal of Applied Sciences (ISSN: 2321 – 0893) Volume 03 – Issue 01, February 2015 Asian Online Journals (www.ajouronline.com ) 146 Estimating Aquifer Transmissivity by the Application of Electrical Resistivity Data and Dar Zarrouk Parameters in Owhelogbo, Isoko North LGA, of Delta State, Nigeria J. C. Egbai 1* , R. E. Iserhien-Emekeme 2 , C. O. Aigbogun 3 and Efeya Pius 4 1 Department of Physics, Delta State University, Abraka, Nigeria 2 Department of Physics, Delta State University, Abraka, Nigeria 3 Department of Physics, University of Benin, Benin City, Nigeria 4 Department of Physics, Delta State University, Abraka, Nigeria * Corresponding author’s email: jamesegbai@ yahoo.com ____________________________________________________________________________________________________________ ABSTRACT---- Thirteen Vertical Electrical Soundings using Schlumberger configuration with a maximum current electrode separation of 500m was carried out in Owhelogbo to determine the aquifer parameters. The data obtained were analysed first by curve matching before computer iteration to obtain the model parameters in terms of resistivity, thickness and lithology of the various layers. The Dar-Zarrouk parameters were used to obtain the hydraulic conductivity, K from aquifer conductivity σ and longitudinal conductance S. The hydraulic conductivity, Kσ values and the transmissivity of the aquifer layers were obtained for the various locations. VEV 4 and VES 2 have the highest and lowest transmissivity of 330.0m 2 /day and 140.0m 2 /day respectively. Keywords---- aquifer parameters, Dar-Zarrouk parameters, Owhelogbo, hydraulic conductivity, Resistivity _________________________________________________________________________________________________ 1. INTRODUCTION Owhelogbo lies between latitude 5 0 35 1 N and 5 0 40 1 N and longitude 6 0 18 1 E 6 0 24 1 E. It is bounded by Ozoro in the East and Orogun in the West while in the North by Abbi and South Otor Owhe. The area has flat terrain with no mountains or hills. It has good roads. It experiences dry and wet seasons with rainy season starting from April to October while the dry season start from November to April. Rain forest is the vegetation of the area. Transmissivity of aquifer expresses the degree of the aquifer characteristics to transmit water in a given geologic formation. It could also be known as the rate at which groundwater is transmitted through a unit width of an aquifer under hydraulic gradient (Allaby, 2008). It is the product of the hydraulic conductivity and thickness of the aquifer. Aquifer are large body of permeable material where ground water is present in the saturated zone in the other words it simply refers to rock or soil mass which not only contains water, but from which can be readily abstracted in significant quantities (Katty et al , 1997). Good aquifers have high permeability such as sand stone and gravel, have high underground storage reservoir which are known for high porosity and permeability (County, 1997). The estimation of aquifer transmissivity by the application of electrical resistivity and Dar Zarrouk parameters have been carefully reviewed by many geophysicists (Niwas and Singhai, 1981, Mazac et al., 1985; Onuoha and Mbazi, 1988; Huntley, 1986; Mbonu et al, 1991; Ijeh and Onu, 2012, Imali and Dharmgunwardhane, 2013; Udoinyang and Igboekwu, 2012). The evaluation of aquifer transmissivity using Dar Zarrouk parameters and electrical resistivity data was applied in the sedimentary basin area of Owhelogbo Isoko North Local Government Area of Delta State, Nigeria. The aim of electrical resistivity method is to measure the potential difference due to flow of current in the ground. The calculation aquifer transmissivity is as a result of the knowledge of layer thickness got from the model parameters; interpretation of resistivity sounding data and hydraulic conductivity derived from the geophysical and hydrogeophysical parameters.