Patent ID: 7937222
Filing Date: 2011-05-03
Classification: G01V

Abstract:
1. A computer-implemented method for determining water saturation within a subterranean reservoir by transforming a deep-reading formation resistivity measurement from a resistivity measuring instrument having at least one receiver coil in a reservoir, said method including the steps of: estimating with a reservoir simulator process a spatial distribution of a parameter related to water conductivity at locations beyond an immediate vicinity of wells within said reservoir; combining said spatial distribution of said parameter related to the water conductivity with a spatial distribution of resistivity as obtained from said deep-reading formation resistivity measurement from the resistivity measuring instrument; deriving a spatial distribution of water saturations at said locations beyond said immediate vicinity of wells; obtaining a first water saturation distribution derived from simulation of the reservoir using reservoir parameters estimated from prior knowledge of the reservoir; obtaining a second water saturation distribution derived from the deep-reading resistivity measurement using inversion parameters; repeating the step of obtaining said first water saturation after changing one or more of said reservoir or inversion parameters until said first and second water saturation distribution converge within a predefined tolerance; and wherein the simulation is used to obtain the first water saturation distribution and a water salinity or conductivity distribution.