Issues of the journals Геофизика 2008 y. issue 5

The Use of First Fresnel Zone Radius in Seismic Exploration

(Zavalishin B.R. )

Wave information within the first Fresnel zone is sufficientfor the solution of an inverse problem. It means that migration velocity is also measurable with it. To make it feasible, the optical principle of imaging should be used. Absence of a smoothing effect, inevitable with multi-kilometer offsets is the main advantage of this approach. It promises more detailed images. The result, inaccessible to the usual method, is achievable due to the use of additional information in the form of a wave diffracted by the aperture.......

  • 2008  № 5, pp. 3-7

Seismic Reciprocity Justification for Layered Media. Part 3

(Denisov M.S. )

The expression allowing the computation of the geometrical spreading factor of a reflected and transmitted wave for the model of earth with locally-homogeneous layers with curved boundaries is studied, the effect of wave conversion is accounted for. The symmetrical properties of this expression prove that the seismic reciprocity principle holds true for the direct and reflected waves in layered earth andfor both the monotype and converted waves. The symmetrical properties of the reflection and transmission coefficients are studied for the monotype and converted waves.......

  • 2008  № 5, pp. 8-17

Selection of Low-Contrast Bodies in Geophysical Fields: Physical and Numerical Approaches

(Nikitin A.A. Zemtsova D.P. )

This paper is dedicated to selection of low-contrast bodies in geophysical fields. Basic attention is paid to the use of seismic attributes while structural modeling and oil saturation estimates. Adaptive energy filtration of seismic isochrones data is proposed for detailed low-contrast bodies identification, and two new seismic attributes to be used while wavelet conversion of the original seismic field - for reservoir rock saturation assessment. Numerical methods used while low-contrast bodies selection include attribute fields splitting by 2-D energy filtration into regional and local components, small anomalies detection against the background noise and integrated analysis of seismic and non-seismic attributes.......

  • 2008  № 5, pp. 18-26

Earth Crust Geophysical Modeling Using 1-SB Regional Line Data

(Galuev V.I. )

Construction of phys-geological models of a structure an earth’s crust by results of geolog-geophysical researches on basic structures is considered. Construction ofphysico-geological models of an earth’s crust, first of all is guided by the given seismic prospecting, as most informative method of deep researches. Data of seismic supervision at construction of physico-geological models are supplemented platform gravic and aeromagnetic measurements of scale 1:200 000. Owing to separate fragments of regional structures electromagnetic supervision magnetotelluric probe MTZ and AMTZ are lead, that provides in a complex with seismic and gravic data construction ofphys-geological models on four basic physical parameters: speeds, density, magnetizations and conductivity. The technology is developedfor creation of these models in ВНИИ-Geosystem on the basis of the geoinformation system INTEGRO, GEOPHYSICS which has received the name GIS-INTEGRO-GEOPHYSICS.......

  • 2008  № 5, pp. 33-42