Method and device for determining horizontal surface relaxation rate

Abstract

The invention provides a method and device for determining horizontal surface relaxation rate. The method comprises the step of carrying out CT scanning on a rock core sample to acquire a gray level image of the rock core sample, carrying out binarization processing on the gray level image to generate a binary image and extract a hole grillage, carrying out nuclear magnetic resonance measurement on the rock core sample to determine measured horizontal relaxation signals, carrying out relaxation simulation on the rock core sample according to the extracted binary image of the hole grillage and the preset surface relaxation rate to determine simulated horizontal relaxation signals, comparing whether the simulated horizontal relaxation time signals coincide with the components at the right-most ends of the measured horizontal relaxation time signals, and choosing the preset surface relaxation rate as the determined horizontal surface relaxation rate of the rock core sample to be outputted when the simulated horizontal relaxation time signals coincide with the component of the right-most ends of the measured horizontal relaxation time signals. The method and device for determining horizontal surface relaxation rate has the advantages of being more reliable in principle, simple in calculating process, easy to achieve, strong in actual operability and the like.

Description

technical field [0001] The present invention relates to well logging technology in oil exploration, in particular to the technology for determining surface relaxation rate by combining nuclear magnetic resonance experiment and CT scanning experiment in clastic rock reservoirs, specifically a method for determining lateral surface relaxation rate method and device. Background technique [0002] Nuclear magnetic resonance technology has been widely used in oil and gas field exploration, mainly used to evaluate the pore structure of complex clastic rock reservoirs, such as the distribution of pore radius and pore throats of different sizes, and is currently the only logging tool that can be used to characterize pore structure information The technology has extremely important application value in the current exploration key areas such as tight sandstone and mud shale and the main contribution fields of domestic energy in the future. [0003] The main mechanism that NMR logging...

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Problems solved by technology

[0008] Accurately determining the relaxation rate of the reservoir surface is crucial to quantitatively estimating the pore throat radius and evaluating the reservoir quality, but foreign technologies have theoretical flaws, because the mercury injection experiment mainly describes the throat information of the reservoir, while the nuclear magnetic resonance The experiment mainly reflects the size of the pores. The method of determining the value of ρ by using the mercury intrusion experiment scale nuclear magnetic resonance experiment has a large theoretical error, and there is no relevant technology in China that can solve this kind of problem.

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