Method for extracting reflection transverse waves from dipole transverse wave data

Abstract

The invention discloses a method for extracting reflection transverse waves from dipole transverse wave data and relates to the technical field of array sound wave logging information treatment and application. The method includes steps of 1, performing waveform restoration on dipole transverse waves; 2, performing band-pass filtering on the transverse wave data; 3, performing time slowness analysis on the transverse wave data and acquiring transverse wave change range in different depths; 4, establishing a transverse wave data propagation matrix; 5, solving reflection transverse wave data. According to the invention, dipole transverse wave information and instrument structure information are combined for comprehensive analysis, multiple direct wave speeds are adopted for filtering treatment in stratums having severe transverse wave dispersion, so that direct wave removal incompleteness caused by single-speed filtering is avoided.

Description

technical field [0001] The invention relates to the technical field of array acoustic logging data processing and application, in particular to a method for extracting reflected shear waves from dipole shear wave data collected by array acoustic logging. Background technique [0002] Extracting reflected shear waves with azimuth information from dipole shear wave data is a key technology in array acoustic wave data processing, laying the foundation for migration imaging processing. Recognition accuracy of equal reflectors. [0003] At present, the methods of extracting reflected waves from array acoustic wave data mainly include median filtering method, F-K filtering method, and high-resolution Radon transform method. [0004] Disadvantages of the prior art: 1. Median filtering is very difficult to select the window length for formations with different mode waves and different acoustic wave speeds. If the window length is too small, a large amount of direct waves will remai...

AI Technical Summary

Problems solved by technology

[0004] Disadvantages of the existing technology: ① It is very difficult to select the window length for different mode waves and formations with different acoustic velocities by median filtering. If the window length is too small, a large number of direct waves will remain, and if the window length is too long, part of the reflected waves will be filtered out. And the processing efficiency is low; ②F-K filtering is mainly due to the influence of the sampling law, it is easy to cause the Gibbs phenomenon, resulting in spectrum leakage and false waves; ③The main problem of the high-resolution Radon transform method is that the source distance of the acoustic wave instrument is relatively large Short and low number of receivers, resulting in frequent aliasing and endpoint effects

[0006] The prior art represented by the above-mentioned patents does not take into account the problem of direct wave dispersion. The method of filtering at the velocity of a single mode wave cannot completely filter the direct wave in some formations where direct wave dispersion is serious. In addition, thus affecting the accuracy of the reflected wave signal

The current method of extracting reflected waves does not specifically deal with reflected shear waves, so special technical methods are needed to solve them

Images