Low signal-to-noise ratio zone shallow wave impedance interface static correction

Low signal-to-noise ratio zone shallow wave impedance interface static correction

  • CN 103,576,200 B
  • Filed: 07/19/2012
  • Issued: 11/16/2018
  • Est. Priority Date: 07/19/2012
  • Status: Active Grant
First Claim
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1. a kind of low signal-to-noise ratio area shallow-layer high-amplitude wave impedance interface static correcting method, feature is through the following steps that realize:

  • 1) near-surface investigation and seismic prospecting are carried out to exploratory area, or utilizes the exploratory area domain Seismic Stacked Section obtained, near-surface investigationInformation material determines shallow-layer there are high-amplitude wave impedance interface, and the high-amplitude wave impedance interface is located at low signal-to-noise ratio area in seismic profileShallow-layer, signal-to-noise ratio are relatively high;

    2) seismic first breaks information is applied, seismic wave is iterated to calculate in given initial near-surface velocity structure by chromatography softwareWhen travelling and the difference of first arrival time, the initial near-surface velocity structure of iterated revision are finally inversed by near-surface velocity structure, high-amplitude wave impedance circleFace corresponds to the big position of density, depth of the control high-amplitude wave impedance interface in seismic data inversion radiographic density on inverting radiographic densityDegree, calibrates this depth in near-surface velocity structure, that is, having selected high-amplitude wave impedance interface is near-surface model interface, obtains closeTerrain model;

    3) datum static correction amount is calculated using shallow-layer high-amplitude wave impedance interface as near-surface model interface, chooses high-amplitude wave impedance interfaceSpeed be benchmark face static correction value calculate when replacement velocity, eliminate due near surface rise and fall and low, reduction of speed band caused by,Long wavelength statics, in the earthquake record after correction in, based on short-period static corrections;

    4) refracted wave residual static correction is calculated using the First refraction break information for obtaining shallow-layer high-amplitude wave impedance interface after base-level correctionAmount, calculating back wave residual correction amount can be counted by being increased to high-amplitude wave impedance interface signal-to-noise ratio on seismic profile;

    5) the back wave Value of residual static correction that each shot point and geophone station are calculated using high-amplitude wave impedance interface reflected wave information, is eliminated residualThe short-period static corrections stayed.

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