Method for joint inversion of stratigraphic dip on basis of array induction and anisotropy

Abstract

The invention discloses a method for joint inversion of a stratigraphic dip on the basis of array induction and anisotropy. Firstly, on the basis of array induction electrical resistivity logging data, computational formulas of apparent conductivity and horizontal conductivity of a double-coil system in an inclined heterogeneous stratum are derived; a relation formula of apparent conductivity andhorizontal conductivity of an ideal potentiometric electrode system in an infinitely thick transverse anisotropic stratum is introduced; an anisotropic parameter calculation model of an target stratumsection is built; and apparent conductivity and horizontal conductivity of the target stratum section are obtained through processing with array induction electrical resistivity logging, a functionalrelational expression is built through the apparent conductivity, the horizontal conductivity and anisotropy, and the method for joint inversion of the stratigraphic dip through array induction and anisotropy is formed. The method is applied in a new well, the stratigraphic dip of the target stratum section is obtained, the stratigraphic dip and electric imaging logging are processed to obtain the stratigraphic dip, data dependency is good, so that the tight sandstone stratigraphic dip is calculated accurately through array induction electrical resistivity logging data, precision is high, andreliable data are provided for looking for a tight gas reservoir trap in the future.

Description

technical field [0001] The invention belongs to the technical field of logging evaluation of tight sandstone reservoirs in petroleum exploration, and relates to a method for reversing formation dip angles in tight sandstones by using the anisotropy calculated jointly by conventional logging and array induction logging. Background technique [0002] The formation dip parameters of unconventional tight sandstone reservoirs are mainly obtained by direct measurement of formation dip logging tools and fine interpretation processing of electrical imaging logging, and are rarely calculated by joint inversion of conventional basic logging data. At present, based on the principle of electromagnetic induction, it is mainly to study the characteristics of array induction affected by dip angle and the correction method based on array induction logging affected by dip angle, and rarely use conductivity logging curves and formation anisotropy to continuously quantify formation dip inversi...

AI Technical Summary

Problems solved by technology

However, currently, in heterogeneous formations, the current line of array induction logging is no longer rotationally symmetric about the tool axis due to the influence of formation dip, but flows along a spatially complex trajectory, which makes the result of array induction synthesis processing abnormal

Images