Multiwave Wavelet Study And Lithology Parameter Inversion In Depth Domain

Based on seismic data processing and lithology parameter inversion in time domain,and with the application of pre-stack depth migration,the advantages of seismic data processing in depth domain are becoming obvious increasingly. People begin to take into account lithology parameter inversion in depth domain. Multiwave wavelet and lithology parameter inversion in depth domain are investigated emphatically.Additionally, in order to study complex stratigraphy analysis and lithology, this method not only uses P wave but also uses message of S wave, P wave and P-SV wave. So more lithology and reservoir parameters for gas reservoir depiction are been obtained. In this thesis.it is not only including P wave wavelet study and P wave lithology parameter inversion in depth domain but also including P-SV wave wavelet study and P-SV wave lithology parameter inversion in depth domain, Finally, in order to validate reliability and stability of the inversion method. theoretical and practical data are been processed.The achievement of the thesis is gained as follows:(1) Refering to wavelet definition in time domain.The definition of wavelet in depth domain is been obtained .By formula k=f/v and wavelet waveform .The inherent relation of different wavelet type is revealed. Based on analytical method of wavelet resolution in time domain .The lateral and vertical maximum resolution in depth domain is derived and tested by modeling.(2) Using convolution model synthetic seismogram in time domain and depth domain is been contrast and the essence distinction is revealed.The wavelet in depth domain is extracted based on multitrace statistical extracting wavelet in time domain. Seismic decovolution profiles in depth domain are been compared with one in time domain.(3) The reliability and the stability of lithology parameter inversion method in depth domain is analysed by the studies of basic theory in generalized linear. By involution model the inversion equation of wave impedance,velocity and density in depth domain is derived, The profiles of wave impedance,velocity and density are respectively inversed in depth domain and time domain,and the method is proved by real seismic data.(4) .The inversion equation of velocity of S wave and P wave and density is derived by simplidy Zoeppritz function. The elastic impedance parameter can be obtained by using P-SV wave. The theory data processing have valiated the correctness of the method.