Method and system for correcting well logging synthetical histogram of carbonate rock stratum

Abstract

The invention provides a method and system for correcting a well logging synthetical histogram of a carbonate rock stratum. The method comprises the following steps: obtaining the well logging information of the carbonate rock stratum on which well-logging synthetical histogram correction needs to be performed, and the lithologic classification of a cored carbonate rock stratum; generating a target discrimination function by utilizing a Fisher discrimination method according to the lithologic classification of the cored carbonate rock stratum and the well logging information; identifying lithological characters of an uncored carbonate rock stratum of the carbonate rock stratum to perform well-logging synthetical histogram correction by utilizing the target discrimination function; and correcting the well-logging synthetical histogram of the carbonate rock stratum on which well-logging synthetical histogram correction needs to be performed according to an identification result. According to the method disclosed by the invention, a relationship between the lithological characters and a well logging response is established by utilizing the drilling and coring information and the well logging information, the re-identification of lithological characters based on Fisher discriminant analysis is realized, and an original low-precision well logging histogram is corrected, so that the precision of a lithologic section is improved.

Description

technical field [0001] The invention relates to the technical field of oil and gas exploration, in particular to a method and system for correcting a comprehensive histogram of mud logging in carbonate formations. Background technique [0002] The comprehensive histogram of formation logging is the most basic data in petroleum geological research. The study of single well sedimentary facies depends on accurate lithology profile, the more accurate the mud logging profile, the more accurate the division of single well facies. At present, the acquisition of mud logging sections mainly depends on cuttings logging. However, the mud logging work at the drilling site is limited by time, experience, and environment, and the accuracy of the original mud logging section obtained is often poor, especially for carbonate formations with small lithological differences. At present, the lithology of mud logging sections in carbonate rock formations is very single, which cannot reflect the...

AI Technical Summary

Problems solved by technology

However, the logging work at the drilling site is limited by time, experience, and environment, and the accuracy of the original logging profile obtained is often poor, especially for carbonate formations with small lithological differences.

At present, the lithology of mud logging sections in carbonate rock formations is very single, which cannot reflect the content and lithology changes of carbonate rock particles, limestone, and grains, which restricts the study of sedimentary facies and sequence stratigraphy

Although thin slices of cuttings can correct the mud logging profile, it is time-consuming and expensive, and there are errors in depth homing

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