Abstract: A method of determining the distribution of shales, sands and water in a reservoir including laminated shaly sands using vertical and horizontal conductivities derived from nuclear, NMR, and multi-component induction data such as from a Multicomponent Induction Logging Tool

Abstract: The present invention is method of determining the distribution of shales, sands and water in a reservoir including laminated shaly sands using vertical and horizontal conductivities derived from nuclear, NMR, and multi-component induction data such as from a Transverse Induction Logging Tool (TILT). Making assumptions about the anisotropic properties of the laminated shale component and an assumption that the sand is isotropic, the TILT data are inverted. An estimate of the laminated shale volume from this inversion is compared with an estimate of laminated shale volume from nuclear logs using a Thomas-Stieber and Waxman-Smits model. A difference between the two estimates is an indication that the sands may be anisotropic. A check is made to see if a bulk water volume determined from the inversion is greater than a bulk irreducible water volume from NMR measurements. In one embodiment of the invention, NMR data are then used to obtain sand distribution in the reservoir.

Abstract: The total porosity of said formation, a fractional volume of the shale, and a resistivity of the shale are determined in a laminated reservoir including sands that may have dispersed shales therein. A tensor petrophysical model determines the laminar shale volume and laminar sand conductivity from vertical and horizontal conductivities derived from multi-component induction log data. The volume of dispersed shale and the total and effective porosities of the laminar sand fraction are determined using a Thomas-Stieber-Juhasz approach. Removal of laminar shale conductivity and porosity effects reduces the laminated shaly sand problem to a single dispersed shaly sand model to which the Waxman-Smits equation can be applied.

Abstract: The distribution of shales, sands and water in a reservoir including laminated shaly sands using vertical and horizontal conductivities is derived from nuclear, NMR, and multi-component induction data. The multicomponent data are inverted and an estimate of the laminated shale volume from this inversion is compared with an estimate of laminated shale volume from nuclear logs. The bulk water volume determined from the inversion is compared with a bulk irreducible water volume from NMR measurements. NMR data are then used to obtain a sand distribution in the reservoir and this sand distribution is used in a second inversion of the multicomponent data. Alternatively, a bulk permeability measurement is used as a constraint in inverting the properties of the anisotropic sand component of the reservoir. From the resistivities of the sand laminae, empirical relations are used to predict anisotropic reservoir properties of the reservoir.

Abstract: The total porosity of a formation, a fractional volume of the shale, and a resistivity of the shale are determined in a laminated reservoir including sands that may have dispersed shales therein. A tensor petrophysical model determines the laminar shale volume and laminar sand conductivity from vertical and horizontal conductivities derived from multi-component induction log data. The volume of dispersed shale and the total and effective porosities of the laminar sand fraction are determined using a Thomas-Stieber-Juhasz approach. Removal of laminar shale conductivity and porosity effects reduces the laminated shaly sand problem to a single dispersed shaly sand model to which the Waxman-Smits equation can be applied.

Abstract: The present invention is method of determining the distribution of shales, sands and water in a reservoir including laminated shaly sands using vertical and horizontal conductivities derived from nuclear, NMR, and multi-component induction data such as from a Transverse Induction Logging Tool (TILT). Making assumptions about the anisotropic properties of the laminated shale component and an assumption that the sand is isotropic, the TILT data are inverted. An estimate of the laminated shale volume from this inversion is compared with an estimate of laminated shale volume from nuclear logs using a Thomas-Stieber and Waxman-Smits model. A difference between the two estimates is an indication that the sands may be anisotropic. A check is made to see if a bulk water volume determined from the inversion is greater than a bulk irreducible water volume from NMR measurements. In one embodiment of the invention, NMR data are then used to obtain sand distribution in the reservoir.