Seismic data de-noising method adopting adaptive wavelet threshold function

A technology of wavelet threshold and seismic data, applied in the field of oil and gas seismic exploration, can solve the problems of signal oscillation, time-varying signal de-noising effect is limited, unsatisfactory, etc.

Inactive Publication Date: 2018-02-16
SOUTHWEST PETROLEUM UNIV
View PDF1 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, these two threshold functions still have defects: when using hard threshold denoising, because the function is discontinuous, the reconstructed signal will oscillate, and many artificial noise points will be generated at the edge of the image
However, when this method reduces the wavelet coefficient with a large absolute value, there is always a constant deviation, which directly affects the degree of approximation between the reconstructed signal and the real signal, resulting in a certain loss of high-frequency information, and the result will lead to blurred edges of the image.
In practical applications, using soft threshold to denoise the signal is relatively smooth, but there is a large signal distortion, and using hard threshold to denoise the effect is not ideal, and the denoising effect on time-varying signal is limited

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Seismic data de-noising method adopting adaptive wavelet threshold function
  • Seismic data de-noising method adopting adaptive wavelet threshold function
  • Seismic data de-noising method adopting adaptive wavelet threshold function

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0029] In order to improve the quality of seismic data in areas with low signal-to-noise ratio, the noise and effective signals are separated to achieve pre-stack denoising of seismic data. This method is used to denoise seismic data.

[0030] First, for the noisy signal f i (t) Do wavelet transform to get wavelet coefficient W j,k , input the noisy channel set f i (t), then find the variance σ i (t), find the adaptive weighted superposition s(t), where,

[0031]

[0032] n indicates that the selected adaptive window starts from the nth channel, m is the window length, i indicates the i-th channel, and t indicates time t, and iteratively calculates the adaptive variance σ point by point i,new (t), where σ i,new (t)=[f i (t)-s(t)] 2 , and then judge whether σ i,new (t)-σ i-1,new (t)i,new (t) replace the original variance σ i (t) Re-process the data, if so, then substitute the adaptive variance into to obtain the threshold λ, Create a new threshold function:

[0...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a seismic data de-noising method adopting an adaptive wavelet threshold function. The method addresses the problem that the quality of seismic data in a low signal-to-noise ratio region of oil and gas seismic exploration cannot meet the requirements of treatment and interpretation. By establishing a new threshold function overcoming the defects of hard and soft thresholdsand using wavelet transform as a core idea, the de-noising goal of seismic data is gained and a new threshold function is determined. Compared with the current similar technologies, the method has theadvantages that the de-noising result is closer to original useful signals and the quality of the seismic data is greatly improved.

Description

technical field [0001] The method of the invention belongs to the field of oil and gas seismic exploration, and relates to the design and application of seismic data denoising methods, and the method is effective for oil and natural gas seismic exploration in all regions. technical background [0002] The complex high and steep structural areas in piedmont rich in oil and gas resources have become the focus of current seismic exploration. With the refinement of exploration, noise interference is often very serious in areas with complex structures and low signal-to-noise ratio. If pre-stack records Without denoising processing, it will lead to unclear horizons or unreal structures on the final stacked section, making the quality of seismic data not meet the processing requirements, thus restricting the further improvement of seismic exploration in this area. [0003] The purpose of denoising seismic data is to suppress the noise on the original record as much as possible, but...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01V1/36
CPCG01V1/36G01V2210/30
Inventor 罗仁泽代月李阳阳赵万明罗翔宇
Owner SOUTHWEST PETROLEUM UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products