Issues of the journals Геофизика 2009 y. issue 4

Reaction of Fractured Block Structures Towards Seismoacoustic Treatment and Natural Vibrations. Part 2. Fractures Interaction Mechanisms

(Fayzullin I.S. Dyakonov B.P. )

In the field of elastic fluctuations there is an interaction of cracks, grouping in a kind of cluster and extended systems that is fixed by a spotty picture of distribution of intensity of scattering waves on many areas and is shown in non-uniform permeability and a saturation of layers. Efficiency of operated influences raises the autoemission mechanism of excitation and go-ahead transfer of elastic Impulses from dynamically extending cracks. Besides, in crack breeds there are quasistatic local accumulation and changes of strain in which it is held in remembrance the previous loadings that is observed in after-action effect. Results of field supervision of crack changes in the course of seismoacoustic influence are considered and speak.......

  • 2009  № 4, pp. 9-15

Estimating Regional Seismic Signal Parameters Using Low-Aperture Group of Geophones

(Chernykh O.A. )

Small aperture seismic array is operating on the territory of the geophysical observatory Mikhnevo, Moscow region to study weak regional seismicity - tectonic earthquakes, quarry blasts, induced seismicity and other seismic sources. Accuracy and stability of azimuth and slowness estimates for the signals detected by the array were investigated. Analysis of primary and surface waves' arrivals from known regional sources (including the explosion during Sport hotel demolition in Moscow) was performed. Two methods of analysis were applied: frequency-wavenumber (f-k) analysis and correlation parameter method. Their abilities for azimuth and apparent velocity estimation are determined. Correlation parameter method requires shorter windows to obtain stable result and provides more stable and accurate slowness estimates for surface waves than f-k-analysis. Also, the ability of the array to estimate weak signal parameters is demonstrated. Weak P-wave arrivals from known regional blast is amplified and picked out by means beam-forming of signal and its azimuth and slowness fit its arrival time.......

  • 2009  № 4, pp. 16-23

Advanced Technique for Salinated Terrigenous Reservoir Porosity Studies Using Well Logging Data

(Zoloeva G.M. Nikiforova O.G. Postnova O.V. )

. This article is dedicated an actual problem of accuracy increasing by estimation porosity of terrigenous rocks complicated by salinization and timed to Vendian-Cambrian period. Investigation results of yaraktinskiyi horizon sediments of one in some fields on a Nepskiyi crest (set) showed, that low salinization sandstones can be collectors of oil and gas. New approach to division sandstones with different degree of salinization and to account salt cement by determining collector's porosity with neutron gamma-method data are presented.......

  • 2009  № 4, pp. 24-28

Searching for Kimberlite Geological Bodies Using Transient Technologies

(Stogniy V.V. Timofeev A.P. )

The paper describes the results of experimental works by transient electromagnetic method on 8 kimberlite pipes with different geological conditions located in the Yakutian diamondiferous province. 3D modeling of anomalous effects caused by enhanced conductivity of kimberlite bodies has been performed. It is indicated that besides anomalies of enhanced electroconductivity anomalies stipulated by enhanced induced polarization of kimberlites are registered above the investigated kimberlite pipes, which is an additional criterion during prospecting of new kimberlite bodies.......

  • 2009  № 4, pp. 29-35