Method for determining fluid saturation in a porous media through the use of CT scanning

Claim 1

A method for determining the multi-phase fluid saturation in a porous media, comprising the steps of: (a) scanning a sample of said porous media with X-rays of differing energies, (b) producing computed tomographic images of said sample at said differing energies, (c) extracting the multi-phase fluid from said sample, (d) scanning said fluid-extracted sample with X-rays of said differing energies, (e) producing computed tomographic images of said fluid-extracted sample at said differing energies, (f) scanning said extracted fluids with X-rays at said differing energies, (g) producing computed tomographic images of said extracted fluids at said differing energies, (h) determining the X-ray mass attenuation coefficients for said sample and each of the fluid phases of said extracted fluids at each of said differing energies from said computed tomographic images, (i) determining the weight fractions of each of said fluid phases from said mass attenuation coefficients, and (j) determining the volume fractions of each of said fluid phases by multiplying said weight fractions by the densities of the respective fluid phases.

Claim 2

A method for determining the multi-phase fluid saturation in a porous media, comprising the steps of: (a) scanning a sample of said porous media with X-rays of differing energies, (b) producing computed tomographic images of said sample at said differing energies, (c) extracting the multi-phase fluid from said sample, (d) scanning said fluid-extracted sample with X-rays of said differing energies, (e) producing computed tomographic images of said fluid-extracted sample at said differing energies, (f) scanning said extracted fluids with X-rays at said differing energies, (g) producing computed tomographic images of said extracted fluids at said differing energies, (h) determining the X-ray mass attenuation coefficients for said sample and each of the fluid phases of said extracted fluids at each of said differing energies from said computed tomographic images, (i) determining the weight fractions of each of said fluid phases from said mass attenuation coefficients, and (j) determining the volume fractions of each of said fluid phases by multiplying said weight fractions by the densities of the respective fluid phases.

Claim 9

A method for determining three-phase fluid saturation in a porous media from the computed tomographic scanning of said media, comprising the steps of: (a) scanning a sample of said porous media with X-rays of first and second energies, (b) producing computed tomographic numbers for said sample at said first and second energies, (c) extracting the three-phase fluid from said sample, (d) scanning the fluid extracted sample with X-rays of said first and second energies, (e) producing computed tomographic numbers for said fluid extracted sample at said first and second energies, (f) scanning said extracted fluid with X-rays at said first and second energies, (g) producing computed tomographic numbers for each phase of said extracted fluid at said first and second energies, (h) determining X-ray mass attenuation coefficients for said sample and each phase of said extracted fluid at each of said first and second energies from said computed tomographic numbers in accordance with the following expression: N.sub.CT =(μ.sub.M -μ.sub.W)/μ.sub.W ×1000 where N CT =computed tomographic number, μ=X-ray mass attenuation coefficient, M=material scanned, and W=water, (i) determining the weight fractions of each phase of said extracted fluid from said X-ray mass attenuation coefficients.in accordance with the following expressions: μ.sub.M(1) =X.sub.a μ.sub.a(1) +X.sub.b μ.sub.b(1) +X.sub.c μ.sub.c(1), μ.sub.M(2) =X.sub.a μ.sub.a(2) +X.sub.b μ.sub.b(2) +X.sub.c μ.sub.c(2), = X.sub.a +X.sub.b +X.sub.c, where X a , X b , and X c are the weight fractions for the three fluid phases a, b, and c; and (1) and (2) are the first and second energies; and (j) determining the volume fractions of each phase of said extracted fluid by multiplying said weight fractions by the densities of the respective fluid phases.

Claim 10

A method for determining three-phase fluid saturation in a porous media from the computed tomographic scanning of said media, comprising the steps of: (a) scanning a sample of said porous media with X-rays of first and second energies, (b) producing computed tomographic numbers for said sample at said first and second energies, (c) extracting the three-phase fluid from said sample, (d) scanning the fluid extracted sample with X-rays of said first and second energies, (e) producing computed tomographic numbers for said fluid extracted sample at said first and second energies, (f) scanning said extracted fluid with X-rays at said first and second energies, (g) producing computed tomographic numbers for each phase of said extracted fluid at said first and second energies, (h) determining X-ray mass attenuation coefficients for said sample and each phase of said extracted fluid at each of said first and second energies from said computed tomographic numbers in accordance with the following expression: N.sub.CT =(μ.sub.M -μ.sub.W)/μ.sub.W ×1000 where N CT =computed tomographic number, μ=X-ray mass attenuation coefficient, M=material scanned, and W=water, (i) determining the weight fractions of each phase of said extracted fluid from said X-ray mass attenuation coefficients.in accordance with the following expressions: μ.sub.M(1) =X.sub.a μ.sub.a(1) +X.sub.b μ.sub.b(1) +X.sub.c μ.sub.c(1), μ.sub.M(2) =X.sub.a μ.sub.a(2) +X.sub.b μ.sub.b(2) +X.sub.c μ.sub.c(2), = X.sub.a +X.sub.b +X.sub.c, where X a , X b , and X c are the weight fractions for the three fluid phases a, b, and c; and (1) and (2) are the first and second energies; and (j) determining the volume fractions of each phase of said extracted fluid by multiplying said weight fractions by the densities of the respective fluid phases.