The extensive application of pre-stack depth migration has produced huge volumes of seismic data,which allows for the possibility of developing seismic inversions of reservoir properties from seismic data in the depth...The extensive application of pre-stack depth migration has produced huge volumes of seismic data,which allows for the possibility of developing seismic inversions of reservoir properties from seismic data in the depth domain.It is difficult to estimate seismic wavelets directly from seismic data due to the nonstationarity of the data in the depth domain.We conduct a velocity transformation of seismic data to make the seismic data stationary and then apply the ridge regression method to estimate a constant seismic wavelet.The estimated constant seismic wavelet is constructed as a set of space-variant seismic wavelets dominated by velocities at different spatial locations.Incorporating the weighted superposition principle,a synthetic seismogram is generated by directly employing the space-variant seismic wavelets in the depth domain.An inversion workflow based on the model-driven method is developed in the depth domain by incorporating the nonlinear conjugate gradient algorithm,which avoids additional data conversions between the time and depth domains.The impedance inversions of the synthetic and field seismic data in the depth domain show good results,which demonstrates that seismic inversion in the depth domain is feasible.The approach provides an alternative for forward numerical analyses and elastic property inversions of depth-domain seismic data.It is advantageous for further studies concerning the stability,accuracy,and efficiency of seismic inversions in the depth domain.展开更多
The extensive use of depth-imaged seismic data produced by pre-stack depth migration(PSDM)leads to the necessity to synthesize seismogram directly in depth domain.However,since seismic wavelet in depth domain is depen...The extensive use of depth-imaged seismic data produced by pre-stack depth migration(PSDM)leads to the necessity to synthesize seismogram directly in depth domain.However,since seismic wavelet in depth domain is dependent on media velocities.The time-domain convolution operation directly used in depth domain does not meet the linear time-invariant condition.In this paper,we present a new method for genuine depth-domain seismic synthesis.This method constructs the velocity-dependent seismic wavelets varying adaptively with the corresponding interval velocities in the depth direction and weights them by the reflectivities,then the synthetic seismic record is obtained by the superposition of these weighted depth-varying wavelets.We applied this method to synthesize the seismic record of both a multi-layered geological model and the field data.The results show that the method can accommodate the intrinsic velocity-dependent variation characteristics of seismic events in depth domain and avoid the redundant depth-to-time and time-to-depth transformations.展开更多
基金supported by the National Natural Science Foundation of China(No.41574130,41874143 and 41374134)the National Science and Technology Major Project of China(No.2016ZX05014-001-009)the Sichuan Provincial Youth Science&Technology Innovative Research Group Fund(No.2016TD0023)
文摘The extensive application of pre-stack depth migration has produced huge volumes of seismic data,which allows for the possibility of developing seismic inversions of reservoir properties from seismic data in the depth domain.It is difficult to estimate seismic wavelets directly from seismic data due to the nonstationarity of the data in the depth domain.We conduct a velocity transformation of seismic data to make the seismic data stationary and then apply the ridge regression method to estimate a constant seismic wavelet.The estimated constant seismic wavelet is constructed as a set of space-variant seismic wavelets dominated by velocities at different spatial locations.Incorporating the weighted superposition principle,a synthetic seismogram is generated by directly employing the space-variant seismic wavelets in the depth domain.An inversion workflow based on the model-driven method is developed in the depth domain by incorporating the nonlinear conjugate gradient algorithm,which avoids additional data conversions between the time and depth domains.The impedance inversions of the synthetic and field seismic data in the depth domain show good results,which demonstrates that seismic inversion in the depth domain is feasible.The approach provides an alternative for forward numerical analyses and elastic property inversions of depth-domain seismic data.It is advantageous for further studies concerning the stability,accuracy,and efficiency of seismic inversions in the depth domain.
文摘The extensive use of depth-imaged seismic data produced by pre-stack depth migration(PSDM)leads to the necessity to synthesize seismogram directly in depth domain.However,since seismic wavelet in depth domain is dependent on media velocities.The time-domain convolution operation directly used in depth domain does not meet the linear time-invariant condition.In this paper,we present a new method for genuine depth-domain seismic synthesis.This method constructs the velocity-dependent seismic wavelets varying adaptively with the corresponding interval velocities in the depth direction and weights them by the reflectivities,then the synthetic seismic record is obtained by the superposition of these weighted depth-varying wavelets.We applied this method to synthesize the seismic record of both a multi-layered geological model and the field data.The results show that the method can accommodate the intrinsic velocity-dependent variation characteristics of seismic events in depth domain and avoid the redundant depth-to-time and time-to-depth transformations.
