Within the 2nd International Geological and Geophysical Conference and Exhibition "GeoEurasia -2019" we are pleased to invite you to attend the following reports of Yandex Terra’s (Seismotech, Ltd.) specialists:
The specificity of seismic data processing based on layer-by-layer description of the environment.
Isakov Mikhail, Leading Geophysicist
The depth image, which fits to the seismic time field and all the additional geological information, is the final result of modern seismic data processing. In order to get such a result, from the very beginning of the processing chart flow we should look at the processing as at the process of the inverse task solving.
Direct and inverse solutions become not only elements of the modern processing sequence, but also a basement for it's designing.
Estimation of absorption parameters and Q-deconvolution in the layered environment model in the generalized statistical model of the seismic trace.
Kunchenko Daniil, Geophysicist
The report is devoted to the applied aspects of research of seismic signals frequency-dependent attenuation study. New technologies of estimation and correction of absorption in seismic records are considered in the work. The theoretical substantiation of new methods of absorption estimation for the statistical model of the seismic trace, the time-variance of which is described by a set of parameters, is given. The parameters describing the time-variance are consistent with the reservoir model of the environment. Our great attention is paid to the development of algorithms for the work in the layered environment. The results of various absorption experiments are presented, ranging from trivial model examples, gradually becoming more complex, and ending with real data experiments. The influence of the phase component of the absorption on the seismic trace and the formation of phase filters for the correction of stretch marks due to absorption are also considered. The methods of optimization of the process of finding the absorption parameters are described. The description of development prospects for this technique is given in the conclusion.
New approaches in optimization of wave fields calculation directly related to the selected target area of seismic response
Shalashnikov Andrey, Leading Software Developer
The report describes the method of calculating and verification of wave field of reflected waves of a certain type of polarization from localized target objects of environment. A special feature of the method is the combination of the wave field continuation operator calculated by means of layer-by-layer recalculation based on the Kirchhoff integral and the finite-difference modelling operator of reflected waves. Parameterization of the wave field continuation operator type is determined on the basis of the frame effective velocity-depth model. The combination of these methods allows: to localize the structure of reflected waves; to reduce the numerical cost of modeling by limiting the use of expensive finite difference operator by the borders of the target area; to eliminate the problems of the finite-difference operator of wave field transformation in complex (for example, low-velocity), but not target areas. The simulation results were verified by means of migration.
We executed the competitive analysis of the received depth AVA-gathers and synthetic gathers, which dynamic was defined by the solution of the vector equation system for plane waves for the continuity of displacements and stresses at the discontinuity boundaries of elastic parameters.