Patent ID: 6879154
Filing Date: 2005-04-12
Classification: G01N,G01V,Y02A

Abstract:
1. A method for determining variations of resistivity index of a family of rock samples as a function of water saturation, in the presence of a non-electrically conducting fluid, comprising: for each sample of the family of rock samples comprising at least first and second pore networks, determining a volume fraction occupied by each pore network by applying to the rock samples an NMR type relaxometry technique; for each sample of the family of rock samples, measuring by mercury injection a pore throat distribution in the at least first and second pore networks; determining experimentally on a sample used as a reference from at least the family of rock samples values of coefficients relating variation of electrical resistivity of the sample used as the reference as a function of water saturation of the sample used as the reference; and determining the resistivity index of all the samples of the family of rock samples on a basis of a variation of parameters describing a layout of the pore networks and using values of the coefficients measured from the sample used as the reference.