Geoelectric Investigations Results along Basic Geophysical Profiles in Eastern Siberia

The geoelectric structure of a sedimentary cover of the south of the Siberian platform is characterized as rather favorable for studying by methods of inductive electroinvestigation. High electric resistance of surrounding rocks of a sedimentary cover considerably differs from resistance of horizons - reservoirs. Saturation of reservoirs by mineralized fluids causes precise correlation of electric properties of horizons and their collecting properties, and also allows to estimate fluid type. <br>Example of the decision of new geoecological problems are monitoring studying of a sedimentary cover in area of large industrial plants. TEM parameters maps and geoelectric sections allow to study evolution of underground geological structure, changing of horizons saturation. <br>During deep-well drilling there are frequent serious problems connected with zones of abnormal high strata pressure and also zones of drilling fluid absorption. Prediction of deep-well drilling conditions - both at a design stage, and during drilling became possible with introduction of new electromagnetic sounding technology. Specificity of this problem is complicated by presence of a powerful source of 50-Hz noise - electrogenerators and other power-plants used during drilling. Results of works with TEM get possibilities to allocate depth intervals with reservoir-horizons, estimate their saturation and predict possible complications.