Three-dimensional array imaging measurement method of dielectric resistivity around wellbore

Abstract

The invention discloses a three-dimensional array imaging measurement method for the resistivity of a well surrounding medium. The method comprises the following steps: I, placing a detector into a well, wherein the detector is provided with an array direction electrode system, the array direction electrode system comprises a plurality of electrodes and works in a plurality of different working modes, each working mode corresponds to one type of electric field distribution, and signals are transmitted at different working frequencies in each working mode; II, calculating a plurality of array lateral curves; III, calculating a plurality of direction lateral curves; IV, imaging the direction lateral curves to obtain a well surrounding 360-degree numerical simulation imaging pattern; V, analyzing the resistivity of heterogeneity stratums in different directions around a well through the array lateral curves, the direction lateral curves and the well surrounding imaging pattern, evaluating inclined wells, highly-deviated wells, horizontal wells, thin layers, heterogeneity stratums, non-induced fractures and holes, quantitatively explaining the resistivity of flushed zones, invasion zones and undisturbed formations, and judging the radiuses of the invasion zones and the flushed zones.

Description

technical field [0001] The invention relates to an array azimuth lateral logging method, in particular to a three-dimensional array imaging measurement method for medium resistivity around a well and an array azimuth electrode system for realizing the method. Background technique [0002] With the needs of oilfield exploration and development, the accuracy of reservoir evaluation is getting higher and higher, and logging instruments are also developing continuously. Some traditional logging tools are increasingly unable to meet the requirements of logging analysis, especially for the detailed description and quantitative orientation of deviated wells, highly deviated wells, horizontal wells, thin beds, heterogeneous formations, non-induced fractures and caves Interpret flushing zone, invasion zone, undisturbed formation resistivity, judge invasion zone radius, flushing zone radius, etc. [0003] The original array lateral instrument uses hardware focusing, and the circuit r...

AI Technical Summary

Problems solved by technology

Some traditional logging tools are increasingly unable to meet the requirements of logging analysis, especially for the detailed description and quantitative orientation of deviated wells, highly deviated wells, horizontal wells, thin beds, heterogeneous formations, non-induced fractures and caves Interpret flushing zone, invasion zone, undisturbed formation resistivity, judge invasion zone radius, flushing zone radius, etc.

[0003] The original array lateral instrument uses hardware focusing, and the circuit realizes the main monitoring control through a closed loop, which is greatly affected by the external environment (such as temperature changes, power fluctuations, etc.), and the residual voltage between the hardware focusing monitoring electrodes cannot be eliminated, and the focusing effect is poor. Moreover, due to the influence of surrounding rock, the vertical resolution is not high enough, and at the same time, it cannot provide heterogeneity information around the well

Micro-resistivity scanning tools and peripheral scanning imaging can conduct directional analysis of the medium around the wellbore, but the detection range is very shallow, and there is no ability to distinguish the induced fractures and holes induced during the drilling process from the original formation fractures and holes

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