Three-dimensional core image pore and throat segmentation method

Abstract

The invention discloses a three-dimensional core image pore and throat segmentation method and belongs to the technical field of image segmentation. The method includes: making communication marks on a three-dimensional core model; subjecting each communication area to three-dimensional distance transformation; calculating a gradient module value of transformed results; seeking key points; subjecting the found key points to framework generation; adding frameworks generated by all the communication areas to obtain a whole three-dimensional core model framework C; calculating pore-diameter cross section area of each framework point in the framework C; seeking pore seed points; subjecting the pore seed points to region growing to mark out each pore of the three-dimensional core model so as to complete three-dimensional core image pore and throat segmentation, wherein mutual contact positions among pores are throats. By the three-dimensional core image pore and throat segmentation method, problems of large errors, over-segmentation, under-segmentation and the like in traditional segmentation method can be reduced, so that three-dimensional core image pore and throat segmentation results are more accurate and effective.

Description

technical field [0001] The invention relates to an image segmentation technology, in particular to a method for segmenting pores and throats of a three-dimensional rock core image, and belongs to the technical field of image segmentation. Background technique [0002] Reservoirs generally refer to rock formations that can store and infiltrate fluids. The microscopic pore structure inside the reservoir directly affects the ability of the reservoir to store oil and gas and seepage characteristics, and this microscopic pore structure ultimately affects the storage content of oil and natural gas. The so-called pore structure refers to the geometric characteristics, distribution and interconnectivity between the pores and throats (referred to as pore throats) in the rock; the pore refers to the unfilled space in the rock, which reflects the storage of the rock. oil and gas capabilities. The throat is the narrow and long part connecting the adjacent pores of the rock. The shape...

AI Technical Summary

Problems solved by technology

[0003] Due to the complex structure of pores, the traditional pore-throat segmentation method for 3D core images has large errors

For example, the existing watershed algorithm has over-segmentation; the max-min ball algorithm cannot accurately determine the position of the throat and cannot accurately reflect the true radius of the narrow and long pores; and the algorithm based on the skeleton segment has under-segmentation

In recent years, researchers have been continuously researching and exploring the problem of pore-throat segmentation in 3D core images, but the current research situation has not yet proposed an efficient and accurate segmentation method for 3D core images

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