Relative non-high-frequency leakage equivalent N-drop smooth spectrum analog deconvolution method

A deconvolution and spectral simulation technology, applied in the field of geophysical exploration, can solve problems such as complex algorithms, strong data sensitivity, and insufficient description of the complexity of the seismic wavelet amplitude spectrum, and achieve improved seismic profile resolution and computational efficiency High and stable effect

CN101201407AActive Publication Date: 2008-06-18BC P INC CHINA NAT PETROLEUM CORP +1
0 Cites 24 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2008-06-18

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention belongs to the seismic data processing and relates to a method by utilizing an equivalent N point smooth spectrum for the simulation of deconvolution. The implementation steps are that the seismic data is collected; the Fourier transform is made for the seismic data at a certain time window; a low pass filter operator of the time domain with an interception frequency of FE and a sampling rate of DT is calculated, which is taken as the equivalent N point smooth operator; FE and DT satisfy the equation that FE*DT is equal to X*DF*1.024; the estimate value of the amplitude spectrum of the seismic wavelet and the reverse wavelet are obtained, which are convoluted with the original seismic data; and the deconvolution seismic data of the time window is obtained. The single peak hypothesis is not applied for the amplitude spectrum of the seismic wavelet in the invention, which suits for complex amplitude spectrum of the seismic wavelet; compared with the least square polynomial fitting, the shape of the simulated amplitude spectrum curve of the seismic record is not affected by the global influence; the invention has the advantages of high calculation efficiency, better stability and improved resolution of seismic profiles.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to geophysical exploration technology, belongs to the deconvolution of seismic data processing, in particular to an equivalent N-point smoothing spectrum simulation deconvolution method capable of obtaining high-resolution seismic sections with relatively no high-frequency leakage. Background technique

[0002] Geophysical exploration needs to further process seismic data after obtaining observation results through conventional methods. Generally, there are three main processing procedures: deconvolution, stacking, and migration. The seismic profile is actually the result of the convolution of the subsurface reflection coefficient sequence and the seismic wavelet. Since the seismic wavelet has a certain length of time and is not a sharp pulse, its convolution effect makes the reflection layer (or event axis) displayed on the seismic section thicker, and the reflection layers adjacent to each other in time are connected or overlapp...

Examples

Embodiment 1

[0083] Embodiment 1 example of the present invention adopts the following steps:

[0084] 1) Seismic data were collected in the field and superimposed, with a duration of 6s and a sampling interval of 4ms, a total of 1000 traces;

[0085] 2) According to the frequency characteristics of seismic data from shallow to deep, artificially divide seismic data into 3 time windows: 0-1500ms, 1500-2500ms, 2500-6000ms;

[0086] 3) Perform Fourier transform on the seismic data of time window 1 (or time window 2, time window 3), and obtain the seismic record amplitude with frequency sampling interval DF of 0.4882812 Hz (time window 2 is 0.976563 Hz, time window 3 is 0.2441406 Hz) Spectrum;

[0087] 4) The cut-off frequency FE is calculated as 30 Hz, the sampling interval DT is 1 ms (time window 2 is 2 ms, time window 3 is 0.5 ms), and a time-domain low-pass filter with 201 samples is used as an equivalent N-point smoothing operator; Here FE*DT=X*DF*1.024, take X=0.06s, fix FE=30Hz, from...

Embodiment 1

[0094] The result of embodiment 1 sees Figure 5 shown.

[0095] Embodiment 2 of the present invention adopts the following steps: wherein the steps different from the above embodiment 1 are:

[0096] 2) According to the frequency characteristics of seismic data from shallow to deep, artificially divide seismic data into three time windows: 0-1000ms, 1000-3000ms, 3000-6000ms;

[0097] 3) Perform Fourier transform on the seismic data of time window 1 (or time window 2, time window 3), and obtain the seismic record amplitude with frequency sampling interval DF of 0.976563 Hz (time window 2 is 0.4882812 Hz, time window 3 is 0.2441406 Hz) Spectrum;

[0098] 4) Take the sampling interval DT as 2 ms, the cut-off frequency FE as 25 Hz (the time window 2 is 12.5 Hz, the time window 3 is 6.25 Hz), and the time-domain low-pass filter with 201 samples as the equivalent N-point smoothing operator; Here FE*DT=X*DF*1.024, take X=0.05s, fixed sampling rate DT=2ms, and calculate the value ...