Method for determining position of reflection interface of seismic data

Abstract

The invention provides a method for determining the position of a reflection interface of seismic data, and belongs to the field of petroleum geophysical exploration. The method includes: (1) supposing seismic waves as f (t), performing Hilbert transform of the f (t), calculating analytic signals of real seismic signals, and obtaining the instantaneous amplitude, the instantaneous phase section Theta (t), and the instantaneous frequency of the seismic waves f (t); (2) performing first-order differential operation based on the instantaneous phase section Theta (t) of the seismic waves, and obtaining the instantaneous phase first-order difference G (t); and (3) obtaining F (t)=-f (t) via the polarity reverse processing of the seismic data f (t), performing Hilbert transform of the F (t), obtaining the instantaneous phase section Theta1 (t), performing first-order differential operation of the instantaneous phase section Theta1 (t), obtaining the instantaneous phase first-order difference j (t) of the seismic waves after polarity reverse, and calculating J (t)=-j (t) via the calculation of the opposite number of the j (t).

Description

technical field [0001] The invention belongs to the field of petroleum geophysical exploration, and in particular relates to a method for determining the position of a reflection interface of seismic data. Background technique [0002] In geophysical exploration, the propagation of reflected waves will produce changes in speed and direction at the interface of the crustal medium. These are the singularities of geophysical signals. Judging the size and position of the singularity can explain the abnormal phenomenon, so The determination of the reflective interface position has special significance for geophysical exploration research. When there is an interface in the underground rock layer, the reflected wave returning to the ground will cause the ground to vibrate. At this time, all the seismic channels in an array will also jump, so there will be an event composed of crests and troughs on the seismic record. Generally, after the formation contains oil and gas, it is quite...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problems existing in the above-mentioned prior art, to provide a method for determining the position of the reflection interface of seismic data, aiming at the shortcomings of using neural network for event tracking, low efficiency and a large number of iterative operations that cannot meet real-time processing , through the Hilbert transform of the seismic data, the virtual seismic record is obtained, and then the instantaneous amplitude and instantaneous phase are obtained, and the sum of the instantaneous amplitude and the instantaneous phase of the seismic record before and after polarity reversal is weighted to obtain the composite attribute, Utilizing this compound attribute can identify the position of the seismic reflection interface more accurately and reliably, and can also obtain accurate event detection results

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