Geometric correction method and apparatus for projection data of nanopore structure of shale

Abstract

Embodiments of the invention provide a geometric correction method and apparatus for projection data of a nanopore structure of a shale. The method comprises the steps of performing longitudinal offset correction by utilizing a plane integration cross check algorithm; and performing horizontal offset correction by utilizing an edge detection-based nearest image primitive similarity algorithm. The projection data is subjected to the longitudinal correction through the plane integration cross check algorithm, and the projection data is subjected to the horizontal correction through the edge detection-based nearest image primitive similarity algorithm, so that the pore imaging resolution of a sample is increased, artifacts in the projection data are removed, noises in the projection data are suppressed, and description of nanoscale pore throats of the sample and micron-sized pores can be realized.

Description

technical field [0001] The invention relates to the technical field of geophysical detection, in particular to a geometric correction method and device for shale nano-pore structure projection data. Background technique [0002] In recent years, micro-nano CT technology has been more widely used in fields including geology, geochemistry, and geophysics. Taking shale as an example, due to its special shale oil and gas storage method, the distribution of nano-scale pore throats inside Research is extremely important. It is difficult to realize the study of shale micro-nano pores non-destructively by traditional methods. The use of X-ray scanning has difficulties such as insufficient resolution, low signal-to-noise ratio, and difficulty in imaging weakly absorbing objects. The introduction of the third-generation synchrotron radiation light will provide the hardware possibility to improve the resolution at the light source level, but the problem it brings is the possible offse...

AI Technical Summary

Problems solved by technology

It is difficult to study the micro-nano pores of shale non-destructively by traditional methods. The use of X-ray scanning has difficulties such as insufficient resolution, low signal-to-noise ratio, and difficulty in imaging weakly absorbing objects.

The introduction of the third-generation synchrotron radiation light will provide the hardware possibility to improve the resolution at the light source level, but the problem it brings is the possible offset during the rotation of the sample stage. If it is not well corrected, it will produce severe artifacts

The current calibration methods for nano-CT projection data focus on the least squares sine fitting for projection centroids or calibration objects, but the existence of noise will cause problems in the shape of the weighed image, and it is difficult to accurately realize the shale research on micro-nano pores

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