A scanning radioactive well caliper measuring device and method

Abstract

The invention discloses a scanning radioactive borehole diameter measurement method and equipment, which selects a gamma radiation source, sets a plurality of collimation holes at the gamma radiation source, and correspondingly a plurality of near and far gamma detectors record scattering Gamma counting: Gamma counting is the result of the weighted average effect of mud density and formation density, based on the fact that the contribution of mud to detector gamma counting is related to the mud gap, and there is a nonlinear relationship between the two; Gamma counting in various azimuths at different depths along the wellbore forms a method for quantitatively evaluating the size of the wellbore. By setting multiple sets of collimation holes-detectors, the statistical error of gamma counting is reduced, and the accuracy of azimuth and caliper data is improved; the equipment measures in the way of rotating and scanning downhole, and records all azimuths at different depths downhole Caliper data for caliper imaging display.

Description

technical field [0001] The invention relates to a well logging device for measuring borehole diameter by nuclear radiation method and a borehole diameter measuring method based on the measuring equipment, belonging to the technical field of mine geophysics logging. Background technique [0002] With the deepening of exploration and development of oil and gas fields, the accurate description of oil and gas reservoirs and reservoir parameters is the key to formulating oil and gas field development plans to improve recovery and oil and gas production, and geophysical logging is the main technology to directly determine the formation parameters. Radius logging data is an important basis for in-situ stress analysis, real-time drilling monitoring, completion cement volume estimation, logging curve correction, borehole scour evaluation, and storage division. [0003] At present, the caliper measurement methods and equipment mainly include mechanical multi-arm caliper logging and no...

AI Technical Summary

Problems solved by technology

Among them, when the contact mechanical multi-arm caliper measuring instrument is used for logging, the measuring arms in each direction are mechanically displaced according to the change of the caliper, and the caliper data is transmitted to the ground by the cable for recording, realizing multi-directional caliper measurement. The instrument is heavy and relatively complex in structure

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