CN-122014231-A - Distributed optical fiber acoustic logging depth correction method, device, equipment and medium

CN122014231ACN 122014231 ACN122014231 ACN 122014231ACN-122014231-A

Abstract

The embodiment of the application provides a method, a device, equipment and a medium for correcting the depth of a distributed optical fiber acoustic logging, which comprise the steps of analyzing a distributed optical fiber acoustic logging waterfall diagram, determining an optical fiber length range corresponding to the position of a blowout preventer, carrying out fast Fourier transform on distributed optical fiber acoustic logging data in the optical fiber length range, determining the bottom position of the blowout preventer, and carrying out logging depth correction on a distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer to obtain corrected logging depth. In the embodiment of the application, the fiber length range approximately corresponding to the position of the blowout preventer is determined by analyzing the distributed fiber acoustic logging waterfall map, the specific position of the bottom of the blowout preventer is determined by utilizing the fast Fourier transform of the distributed fiber acoustic logging data, and further the logging depth correction is carried out on the distributed fiber acoustic logging curve, so that the corrected logging depth is obtained, and the accurate logging depth is provided for the distributed fiber acoustic logging curve.

Inventors

ZOU YOULONG
LI JUN
SU JUNLEI
ZHANG AIQIN
JIN WUJUN
HUANG XIN

Assignees

中国石油化工股份有限公司
中国石油化工股份有限公司石油勘探开发研究院

Dates

Publication Date: 20260512
Application Date: 20241112

Claims (14)

1. The distributed optical fiber acoustic logging depth correction method is characterized by comprising the following steps of: analyzing a distributed optical fiber acoustic logging waterfall diagram, and determining an optical fiber length range corresponding to the position of the blowout preventer; Performing fast Fourier transform on the distributed optical fiber acoustic logging data within the optical fiber length range, and determining the bottom position of the blowout preventer; and correcting the logging depth of the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer, and obtaining corrected logging depth.
2. The method of claim 1, wherein analyzing the distributed fiber optic sonic logging waterfall graph to determine a range of fiber lengths corresponding to a blowout preventer location comprises: Analyzing the distributed optical fiber acoustic logging waterfall diagram, and determining that the position where the acoustic signal at the top of the optical fiber is strong and the acoustic signal shows regular vibration is the optical fiber length range corresponding to the position of the blowout preventer.
3. The method of claim 1, wherein the performing a fast fourier transform on the distributed fiber optic acoustic logging data over the range of fiber optic lengths to determine a bottom position of the blowout preventer comprises: Performing fast Fourier transform on the distributed optical fiber acoustic logging data within the optical fiber length range to obtain an optical fiber length-frequency waterfall diagram; And analyzing the optical fiber length-frequency waterfall diagram to determine the bottom position of the blowout preventer.
4. The method of claim 3, wherein the analyzing the fiber length-frequency waterfall plot to determine a bottom location of the blowout preventer comprises: and analyzing the optical fiber length-frequency waterfall diagram to determine the position of the low-frequency bottom strong signal as the bottom position of the blowout preventer.
5. The method of claim 1, wherein correcting the depth of log for the distributed fiber optic acoustic log based on the bottom position of the blowout preventer, to obtain a corrected depth of log, comprises: and correcting the logging depth of the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer and the height between the square bushing and the bottom position of the blowout preventer, and obtaining corrected logging depth.
6. The method of claim 5, wherein the performing a log depth correction on the distributed fiber optic acoustic log based on the bottom position of the blowout preventer and the height between the square center of gravity and the bottom position of the blowout preventer to obtain a corrected log depth comprises: According to the formula d c ＝l-(h r +h d ), carrying out logging depth correction on the distributed optical fiber acoustic logging curve to obtain corrected logging depth d c , wherein l is the length of an optical fiber, h r is the bottom position of the blowout preventer, and h d is the height between the square center of gravity and the bottom position of the blowout preventer.
7. A distributed optical fiber acoustic logging depth correction apparatus, comprising: the optical fiber length range determining module is used for analyzing the distributed optical fiber acoustic logging waterfall diagram and determining the optical fiber length range corresponding to the position of the blowout preventer; The bottom position determining module is used for performing fast Fourier transform on the distributed optical fiber acoustic logging data within the optical fiber length range and determining the bottom position of the blowout preventer; And the logging depth correction module is used for carrying out logging depth correction on the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer, and obtaining corrected logging depth.
8. The apparatus of claim 7, wherein the fiber length range determination module is configured to: Analyzing the distributed optical fiber acoustic logging waterfall diagram, and determining that the position where the acoustic signal at the top of the optical fiber is strong and the acoustic signal shows regular vibration is the optical fiber length range corresponding to the position of the blowout preventer.
9. The apparatus of claim 7, wherein the bottom position determination module is configured to: Performing fast Fourier transform on the distributed optical fiber acoustic logging data within the optical fiber length range to obtain an optical fiber length-frequency waterfall diagram; And analyzing the optical fiber length-frequency waterfall diagram to determine the bottom position of the blowout preventer.
10. The apparatus of claim 9, wherein the analyzing the fiber length-frequency waterfall plot to determine the bottom location of the blowout preventer comprises: and analyzing the optical fiber length-frequency waterfall diagram to determine the position of the low-frequency bottom strong signal as the bottom position of the blowout preventer.
11. The apparatus of claim 6, wherein the logging depth correction module is specifically configured to: and correcting the logging depth of the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer and the height between the square bushing and the bottom position of the blowout preventer, and obtaining corrected logging depth.
12. The apparatus of claim 11, wherein the logging depth correction module is specifically configured to: According to the formula h c ＝l-(h r +h d ), carrying out logging depth correction on the distributed optical fiber acoustic logging curve to obtain corrected logging depth d c , wherein l is the length of an optical fiber, h r is the bottom position of the blowout preventer, and h d is the height between the square center of gravity and the bottom position of the blowout preventer.
13. An electronic device, comprising: A processor; a memory; And a computer program, wherein the computer program is stored in the memory, the computer program comprising instructions that, when executed by the processor, cause the electronic device to perform the method of any one of claims 1 to 6.
14. A computer readable storage medium, characterized in that the computer readable storage medium comprises a stored program, wherein the program when run controls a device in which the computer readable storage medium is located to perform the method according to any one of claims 1 to 6.

Description

Distributed optical fiber acoustic logging depth correction method, device, equipment and medium Technical Field The application relates to the technical field of oil and gas exploration and development, in particular to a distributed optical fiber acoustic logging depth correction method, device, equipment and medium. Background The distributed optical fiber acoustic sensing technology utilizes the phase of coherent Rayleigh scattered light to detect signals such as sound or vibration from audio frequency to very low frequency, and linearly restores the amplitude, phase and frequency of sound or vibration at different points of the optical fiber through phase information. The distributed optical fiber sensor has the advantages of high measurement precision, low probability of electromagnetic interference, non-contact measurement, simple and convenient installation, easiness in underground long-term or permanent monitoring and the like, and is widely applied to horizontal well fracturing, liquid production profile interpretation and the like in oil and gas well production. And when the distributed optical fiber acoustic logging is carried out, the optical fiber is taken down along with the steel cable, and acoustic vibration signals of the whole section of optical fiber are continuously measured and recorded, so that a distributed optical fiber acoustic logging curve is obtained. In a distributed fiber acoustic logging, the logging depth is characterized by the length of the fiber. However, characterizing the well depth using fiber length is not accurate, and therefore, depth correction of fiber length is also required to be converted into data interpretable well depths. It should be noted that the information disclosed in the background section of the present application is only for enhancement of understanding of the general background of the present application and should not be taken as an admission or any form of suggestion that this information forms the prior art that is well known to a person skilled in the art. Disclosure of Invention In view of the above, the present application provides a method, apparatus, device and medium for correcting the depth of a distributed optical fiber acoustic logging, so as to solve the problem of inaccurate logging depth in a distributed optical fiber acoustic logging curve in the prior art. In a first aspect, an embodiment of the present application provides a distributed optical fiber acoustic logging depth correction method, including: analyzing a distributed optical fiber acoustic logging waterfall diagram, and determining an optical fiber length range corresponding to the position of the blowout preventer; Performing fast Fourier transform on the distributed optical fiber acoustic logging data within the optical fiber length range, and determining the bottom position of the blowout preventer; and correcting the logging depth of the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer, and obtaining corrected logging depth. In one possible implementation, the analyzing the distributed optical fiber acoustic logging waterfall map to determine the optical fiber length range corresponding to the position of the blowout preventer includes: Analyzing the distributed optical fiber acoustic logging waterfall diagram, and determining that the position where the acoustic signal at the top of the optical fiber is strong and the acoustic signal shows regular vibration is the optical fiber length range corresponding to the position of the blowout preventer. In one possible implementation, the performing a fast fourier transform on the distributed fiber acoustic log data over the range of fiber lengths to determine a bottom position of the blowout preventer includes: Performing fast Fourier transform on the distributed optical fiber acoustic logging data within the optical fiber length range to obtain an optical fiber length-frequency waterfall diagram; And analyzing the optical fiber length-frequency waterfall diagram to determine the bottom position of the blowout preventer. In one possible implementation, the analyzing the fiber length-frequency waterfall plot to determine a bottom position of the blowout preventer includes: and analyzing the optical fiber length-frequency waterfall diagram to determine the position of the low-frequency bottom strong signal as the bottom position of the blowout preventer. In one possible implementation manner, the correcting the logging depth of the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer to obtain the corrected logging depth includes: and correcting the logging depth of the distributed optical fiber acoustic logging curve according to the bottom position of the blowout preventer and the height between the square bushing and the bottom position of the blowout preventer, and obtaining corrected logging depth. In one poss