Geophone Orientation And Multiwave Wavefield Separation Method Of 3D VSP

3D-3C VSP technology can largely solve the problem of difficulty and precisionof the exploration . However, in the well for 3C VSP data acquisition, the current useof three-component geophone is not well directed, therefore, three-componentgeophone recorded wave field to carry out the necessaryinformation must be handled.Three-dimensional three-component surface seismic VSP compared with the biggestadvantage is the ability to receive various types of waves, for subsequent processingand interpretation of the wave field to provide a wealth of information, but thethree-component VSP collected various types of upward and downward They overlapwith the wave must be effective separation of upward and downward wave and Swave.In this paper, three-dimensional three-component VSP characteristics of seismicdata, the main research direction of rotation of the three-component wave fieldseparationissues and problems.(1)First, three-component geophones were coordinate rotation orientation of thedetector received inclined orientation relationship between the three components, andaccording to the coordinates of the three components of rotation before and after theconversion relationship between the three components of the inclined coordinaterotation theory.Finally, the energy characteristics for the azimuth of the horizontalcomponent of the discussion, draw horizontal component of the formula forcalculating the azimuth angle.Using this method on three-component data of theactual shaft rotation direction, and achieved better results, but also verify thefeasibility of the method.(2)In this paper, three-dimensional separation VSP Duo Bobo field, seismic wavepropagation from the kinematic and dynamic point of view, the use of various typesofwave field and the polarization properties of the apparent speed differences of thethree separation methods:τ-p transform,Median filtering, polarization decomposition.In the studyτ-p transformation process,τ-p transform the basic principles andapplication ofwave field separation to analyze to transform the resulting aliasing,truncation effects ofendpoints and study, and proposed to suppress various Effect.Also studied the median filtering method in the separation of wave field, while the effect of different parametersand boundary effects on the impact of the separationresults, and theoretical modelsand real data to test and achieved good separationeffect.Finally, two-dimensional model of the polarization direction of seismic waves,separation of the vertical and horizontal polarization wave decomposition of theapplication and use of vertical and horizontal polarization wave, combined withmedian filter data on multi-wave VSP wavefield separation.