The profile line of geophysical exploration lies along the fairway of the Lena River. A complex of transient electromagnetic soundings (TES) and a common deep point (CDP) method has been used for the exploration. A complete geoelectrical section of sedimentary deposits and the properties of the basic geoelectrical layer have been estimated using TES. In the sedimentary deposits productive layer zones with increased and decreased electrical resistance have been studied. The results of both geoelectrical and seismic analyses prove that the use of both of these methods is very promising.
Transient electromagnetic soundings with a controllable source (TEM) have been tested at performance of prospecting works for hydrocarbons in Western Siberia. During researches high resolution, depth of investigation, locality of research of TEM has been revealed at rather small sizes of installation (it is less than depth of investigated object). As a result of interpretation of TEM field data the map of depths to productive horizon (bajenov formation) on which it is allocated low-amplitude an anticlinal raising is constructed. On the basis of geological interpretation this raising is recognised by perspective on hydrocarbons.
The paper presents some results obtained by transient electromagnetic (TEM) sounding. The measurements were performed in the epicenter part of Chuya earthquake of 2003, which occurred in the nearest mountain frame of Chuya tectonic depression in Gornyy Altai. Regular survey have been continued for 6 years. Electrical prospecting data obtained at the late of the 20th century on the territory of the Chuya depression were analyzed. Field investigation carried out on the territory of this depression in 1980, 2004-2006 allows time history of electrical parameter changes to be traced after great seismic event in this region.
The investigations were carried out in Eastern Siberia on the Ust-Orda national region territory using the groups of methods on direct and alternating current. Multicomponent registration of electrical and electromagnetic parameters has been used. Field data interpretation stage included adaptation of software for a concrete experimental data, substantiation of interpretational models formation methods and the analysis of all a priori information. As a result, quantitative estimations of thickness and geoelectrical parameters of geological complexes were obtained. Moreover, complex tectonic structures were allocated and the most promising areas for detailed works were chosen.