A wave field separation method and device for reflected acoustic wave logging

Abstract

The invention discloses a reflection acoustic logging wave field separation method and device. The method comprises the steps: carrying out the preprocessing of an actual measurement waveform, and calculating the slowness range of a direct wave in the actual measurement waveform after preprocessing; constructing a propagation matrix according to the calculated slowness range; obtaining the waveform of the direct wave through inversion according to the propagation matrix and the actual measurement waveform after preprocessing; removing the waveform, obtained through inversion, of the direct wave from the actual measurement waveform after preprocessing, obtaining a reflection waveform, carrying out the migration imaging of the reflection waveform, and obtaining a final reflection waveform. The device comprises a calculation module, a constructing module, an inversion module, and a migration module. The method solves a more accurate propagation matrix through a slowness time coherence method, gives consideration to a plurality of array types of the direct wave based on a frequency dispersion effect, can stably and effectively extract the reflection wave from the actual measurement wave, and provides more accurate and effective information for the reflection acoustic logging.

Description

technical field [0001] The invention relates to the technical field of reflected acoustic wave logging, in particular to a wave field separation method and device for reflected acoustic wave logging. Background technique [0002] With the deepening of oil and gas exploration and development, people have higher and higher requirements for the resolution and accuracy of geophysical data. Although conventional logging technology has high resolution and precision, it cannot detect areas other than the vicinity of the borehole wall due to the limitation of detection range and detection scale. [0003] The technology of reflecting wave imaging of stratum structures and geological bodies in the range of several meters to tens of meters around the well through acoustic logging in the well is called reflected acoustic logging technology. Increase from one meter to tens of meters. The application prospect of this technology is very huge. It can be used to display the geological inte...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to solve the common problems of low imaging accuracy, poor reliability, and strong multi-solution in the existing reflected acoustic logging technology, and provide a wave field separation method and device for reflected acoustic logging. The degree-time coherence method is used to obtain a more accurate propagation matrix, and multiple formations of the direct wave are considered based on the dispersion effect, which can stably and effectively extract the reflected wave from the measured waveform, thereby providing more accurate and effective information for reflected acoustic wave logging

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