Assiut Univ. J. of Geology 37(2), P-P.189-209 (2008). EMPIRICAL RELATIONSHIP BETWEEN BOREHOLE RESISTIVITY AND HYDRAULIC PARAMETERS IN EL AWKAF AREA, EAST EL OWEINAT, SOUTH WESTERN DESERT M. S. Barseem * and M. M. El Osta ** * Geophysical Department, Desert Research Center, El Matarya, Cairo, Egypt. ** Hydrology Department, Desert Research Center, El Matarya, Cairo, Egypt. Emails: Mostafa_barseem @yahoo.com & drmagedelosta@gawab.com Received:27/9/2008 El Awkaf area is one of the new reclaimed areas of East El Oweinat project. The agricultural and human activities in that area depend mainly on the groundwater of the Nubian Sandstone aquifer, which represents the only source of groundwater. The available electric well logging and pumping test data for twelve wells were used to establish geoelectric and hydraulic parameters. The well logging data indicates that, the area under investigation represents homogenous subsurface succession that is built mainly from Nubian Sandstone with limited lateral changes in thickness of the layers. The lower part of the succession is the water – bearing formation having true resistivity varying from 94.06 to 215.9 Ohm.m. Thickness of this formation ranges between 213 m and 327.13 m. The effective porosity of the saturation zone varies from 15.54% to 25.6% with an average 21.2942%. The transmissivity and hydraulic conductivity that estimated from analysis of pumping test data were compared with there calculated from well logging data. A concordance was obtained between the estimated and calculated parameters with an average error 14.1% to 24.3% for the transmissivity and 14.2% to 24.3% for hydraulic conductivity. The established empirical equations between the estimated and calculated hydraulic parameters can be used to estimate the hydraulic parameters of the Nubian Sandstone aquifer in all sites at which either well logs or vertical electrical sounding measurements are found without performing the pumping tests in the study area. INTRODUCTION The development of groundwater resources and management of its agricultural and human activities depend on the porosity and permeability of water bearing formation. The determination of hydraulic characteristics of the aquifer such as hydraulic conductivity, transmissivity and storativity are generally obtained by analyses of pumping tests. Several formulae have been proposed for computing these parameters, but their validity depends on the various assumptions, such as the type of aquifer, rate of pumping and well storage under field conditions. However, if the number of pump – tested wells and their distribution in the study area are not sufficient or difficult to employ the tests; an alternative approach for the estimation of aquifer hydraulic