Connate Water in Oil and Gas Sands

Abstract

Several investigators have reported evidence of the existence of native orconnate water in oil-and-gas-bearing strata. Both water and salt have beendetected in cores of oil sands that yielded oil and gas exclusively whenproduced. Electrical logs often reveal unexpectedly low resistivity through oiland gas sands, indicating the presence of some material that is a considerablybetter conductor of current than oil and gas. Furthermore, calculations of theoil and gas content of reservoirs based upon production and reservoir-pressuredecline data indicate appreciably lower values than are arrived at under theassumption that the pore space is occupied completely by oil and gas.