Method and device for phase shift attribute based on geosteering

Abstract

The invention provides a method and device for a phase shift attribute based on geosteering, and relates to the technical field of oil and gas seismic exploration interpretation. The method comprisesthe steps that according to a normalized complex seismic channel of a post-stack seismic data body and multiple pieces of preset information of a direction perpendicular to the geologic structure trend, complex value correlation corresponding to various directions is calculated to determine an adjacent model track along each direction; then a complex correlation coefficient matrix corresponding tothe various directions is determined; then an instantaneous phase shift attribute of a point in the complex correlation coefficient matrix corresponding to the various directions is determined as thephase shift of the point; a maximum value of the phase shift of the point corresponding to the various directions as an identification result of the phase shift attribute of the point. The method anddevice for the phase shift attribute based on the geosteering have the advantages that the ancient geomorphological structure illusion with an inclination angle can be identified by using the calculation result of the phase shift, the information of the direction perpendicular to the geologic structure trend is introduced, the weak discontinuous anomalous body border can be better identified, thereby being conductive to determining a weak reflective structure and a minute structure.

Description

technical field [0001] The invention relates to the technical field of oil and gas seismic exploration interpretation, in particular to a method and device for identifying phase shift attributes based on geosteering. Background technique [0002] At present, in the conventional real coherence technology, it is generally to correlate adjacent real seismic traces to obtain the similarity coefficient of adjacent real seismic traces, and then characterize the discontinuity of the underground medium. Because this traditional method uses amplitude for calculation, the reflection coefficient has a great influence on the results. At the same time, for areas with dip angles, structural artifacts may be caused due to the influence of dip angles, which interferes with the analysis and interpretation work. Therefore, the complex coherence technology is developed on this basis, that is, the normalized complex seismic traces are obtained through the Hilbert transform, and the complex corr...

AI Technical Summary

Problems solved by technology

This method overcomes the shortcomings of real coherent technology to a certain extent, but because the signal is smoothed in the process of taking the envelope, the resolution of the calculation result is reduced

[0003] It can be seen that the traditional correlation calculation is seriously affected by the reflection strength due to the use of amplitude attributes, and cannot effectively identify weak reflections and small faults. At the same time, the existing seismic coherence technology is mainly coherent along the main survey line and the contact survey line. A geometric mean result, or coherence of seismic traces in two adjacent elliptical or rectangular regions

These coherence results are generally a comprehensive reflection of the discontinuity of geological bodies. Due to the influence of the dip angle, the calculation results will also show low correlation, which is likely to cause structural artifacts

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