Publications

A seismologiсal survey with several simultaneous sources provides more data per time unit than a conventional one with a single source, and presents an opportunity to improve the seismic recording system. Depending on the type of seismic source (vibrating or pulse), different methods of deblending should be used. Deblending of vibroseismic signals source becomes possible at the stage of correlation processing of vibro-grams. 

Еngineering surveys for the design of facilities with high criticality rating require a switch from methods with discrete assessment of environmental parameters (drilling and static / dynamic sounding), to methods that allow to obtain these values continuously in а massif. The most efficient way to solve this problem is by performing crosshole seismic tomography (CST). The article presents the results of CST during geophysical studies at the site of projected nuclear power plant (NPP).

The simultaneous source technique allows one to improve efficiency and quality of seismic acquisition by using several independent sources that overlap with small time delay. The main problem in working with simultaneous source is deblending. Different methods of separating simultaneous source data use features of a complex wave filed. Our approach offers an iterative scheme with inversion that allows using information about time delays between sources activation and hyperbolic median filtering, that is using kinematic properties of reflected waves. The operation of this algorithm is de...

The application of the CSRMT method with an electric dipole as a controlled source for the mapping of sand and gravel deposit is demonstrated. The survey was fulfilled in the far-field zone of the controlled source and standard magnetoteluric software tools were used for the 2D inversion. Good correlation with borehole sections and VES data confirmed the reliability of the CSRMT results.

The article is devoted to multisource technology—a new direction in geophysics that provides high seismic performance due to the simultaneous use of several seismic sources. The main problem when working with multiple sources is separation of the interfering wave fields. To solve this, we propose a hyperbolic median filtering method, which uses the hyperbolicity of the travel-time curve of reflected waves in a common midpoint gather. Additionally, an inversion algorithm is used to adjust signal amplitudes after separation. This approach demonstrates good results with synthetic data.

The paper describes an operational experience of crosshole seismic testing (CST) applied on a real object. The features of field survey, data processing and analysis of results are demonstrated. On the site three methods of borehole seismic survey were actually used: vertical seismic profiling (VSP), reversed VSP (RVSP), and CST. VSP was implemented in order to build an initial model. RVSP was necessary to clarify the properties of the upper waterless part of the section. CST was the basis for determining the properties of the section.

The paper is devoted to the crosshole seismic testing method realization, carried out at the site of proposed construction of nuclear power plant in Paks, Hungary. The main stages of its realization are described along with data processing algorithms and main results. Conclusions sum up the applicability limits of such a method in low-velocity sections.

The paper considers the possibilities of modern seismic equipment for shallow depths investigations from the point of view of increasing the signal frequency and, consequently, the resolution of seismic methods. The capabilities of vertical seismic profiling (VSP) in single well, reversed VSP (RVSP), and crosshole seismic testing (CST) are demonstrated.

Horizontal welling is a common method for the laying of the pipelines. This technology requires detailed exploration of first 20-30 m of subsurface for searching the optimal path for the welling tools and minimization of the damaging risks. Situations when the pipeline trace crosses the river are very common. In such a case, it becomes necessary to explore geological cross-section just under the river and in the surrounding area. Usually this task is being solved using the following methods: seismic, vertical electrical soundings, electrical resistivity tomography, ground penetration radar.

The paper describes an example of the implementation of crosshole seismic testing for pressure and shear waves at the site of proposed construction of Nuclear Power Plant "Paks-2" (Hungary). Based on the comparision of summary seismograms it was concluded that method demonstrates the best results at distances between wells of 25 27 m.

This paper is intended to compare the results obtained with use of different geophysical methods (geomagnetics, electrical resistivity tomography, ground-penetrating radar and seismics) on a archaeological site and discuss the prospects of such an integration between geophysics and archaeology. The relevant experience thus obtained should help to locate more efficiently the buried structures (graves) in the subsurface. This research was carried out within the framework of the Field Camp 2014 devoted to exploration of the 4th to 7th century burial site near Nizhny Novgorod, Russ...

In this paper, we present an application of the resistivity model based on a modified Archie’s law (Glower et al., 2000), and accounting for a conductivity of clay material, to the Kotlin clayey formation (Vendian age, St. Petersburg, Russia). We compare theoretical prediction of the model with experimental data based on the well logging and laboratory measurements of the core porosity and granulometric composition. We found that the experimental data are in agreement with the model prediction for the case of salty formation water (about 35 g/l).