Issues of the journals Геофизика 2007 y. issue 4

Informative Adequacy-of Measurements in Applied Geophysics

(Kashik A.S. )

The quality of solutions to unstable ill-posed inverse problems in geophysics is determined, among other parameters, by accuracy of their measurements for sounding fields that are described by partial derivative equations. Generalized approach is attempted to selecting measurement systems for tool designs, with such approach expected to ensure sharp increase in solution robustness and accuracy in determination of the subsurface-medium parameters. It is shown that engineering limitations that prevent enhancing the required accuracy in recording geophysical sounding field parameters by several orders of magnitude may be overcome by a proper choice of acquisition systems.......

More
  • 2007  № 4, pp. 7-14

Basics and Field Use of Pre-Stack 3D Deep Seismic Migration

(Gogonenkov G.N. Pleshkevich A.L. Turchaninov V.V. Moroz B.P. )

Two 3D prestack depth migration algorithms based on depth extrapolation and on back-scattering problem are considered. Integral solutions of both problems based on wave Green’s functions for inhomogeneous medium are developed. Simplified solutions were obtained in terms of Born+ray approximation. They were used to create alternative Kirchhoff 3D migration software. Some features of the developed software are discussed, e. g. parallel computing on supercomputer clusters systems. 3D PSDM results of real data acquired in different areas and various seismic and geological conditions are compared with 3D poststack time migration data.......

More
  • 2007  № 4, pp. 15-24

Development of Hybrid Neural Expert System for Seismic Attributes Definition

(Lavrik S.A. Loginov D.V. )

An interesting approach to definition of an optimal (and most informative) subset of the seismic attributes, based on use of intelligent IT technologies, namely the use of hybrid intelligent systems is discussed. The basic features and classification of such systems are described. The technique of hybrid system construction for the definition of informative seismic attributes is proposed.......

More
  • 2007  № 4, pp. 25-28

Integrated Algorithm for Multidimensional Data Clusterization

(Loginov D.V. Belyanushkina M.S. Lukhminsky B.Ye. )

A new combined algorithm of data clustering is presented. This algorithm allows to define the number of clusters when it is not known and get stable partitioning of the data set. Various situations of clusters arrangement for complex algorithm’s work checking were studied. The task was to estimate correct definition of probability of clusters number. Multivariate testing results are also presented. Practical application of this approach in clustering maps of seismic attributes is discussed. These maps can be used for preliminary analysis of seismic facies in the studied areas.......

More
  • 2007  № 4, pp. 29-34
Счетчики