Predicting carbonate rock solid permittivity

摘要

Apparatus and methods for determining the rock solid (matrix) dielectric permittivity for subterranean rocks, such as carbonate rocks, are described. According to some embodiments, this is accomplished by linking the matrix permittivity to the detailed chemical composition of the rock. The linking function is defined by coefficients for each component that can be determined by inversion in a laboratory calibration process such that the function compensates for the permittivity contribution of rock components that may be undetectable through downhole logging procedures.

主权项

1. A computer implemented method of evaluating properties of a subterranean rock formation surrounding a borehole comprising:
receiving composition data reflecting downhole composition measurements made using a gamma ray logging tool at one more locations along the borehole of the rock formation surrounding the wellbore; generating a measure of the rock solid permittivity associated with the rock formation at the one or more locations based at least in part on a function relating the downhole composition data and the measure of the rock solid permittivity; wherein the composition data indicates a plurality of compositional components of the rock that are detectable using the composition measurements, and the function is adapted to compensate, in the measure of the rock solid permittivity, for the contribution of the one or more components that are not detectable using the composition measurements; and wherein the composition data indicates chemical and/or lithology composition of the subterranean rock formation at the one or more locations.