Details of the Abstract
| Title of paper | The results of joint EM data interpretation: paleovalley exploration case study |
| List of authors | Kulikov V.A., Aleksanova E.D., Ionicheva A.P., Korolkova A.V., Shagarova N.M., Shustov N.L. |
| Affiliation(s) | Moscow State University, Moscow, Russia, Nord-West Ltd., Moscow, Russia, GERMC IPE RAS, Troitsk, Russia, Nord-West Ltd., Moscow, Russia, Moscow State University, Moscow, Russia, Moscow State University, Moscow, Russia |
| Summary |
Since 2015, students of Faculty of Geology of Lomonosov Moscow State University during their field training courses have been conducting the research of paleovalleis located near “Aleksandrovka” fieldcamp in the Kaluga Region. The data of VES-IP (vertical electrical soundings with induced polarization), time-domain electromagnetic soundings (TDEM) and audio-magnetotellirics (AMT) were currently obtained along 6 lines with length from 3 to 30 km. The space between sites varies from 35 - 70 m (for TDEM) to 210 m (for AMT). There three systems of paleovalleis in the area C1tl-bb, C2az and N. The results of the joint interpretation of EM data along lines across different types of paleovalley are presented. Interpretation of apparent resistivity curves obtained for layered geological section, allows defining some parameters, which have a narrow range of equivalence. They are different for direct current methods (VES) and low-frequency induction methods (TDEM, AMT). If the geological section consists of alternation of thin layers with different resistivity, in order to satisfy the observed data of both groups of methods, it is necessary to set, in addition to the resistivity of the layer, its anisotropy or to increase the number of layers. The possibilities and advantages of joint interpretation of apparent resistivity curves for VES and TDEM using special version of IPI 2 Win software (A. Bobachev) are shown. The upper part of the resistivity image obtained from joint interpretation VES and TDEM data was used as the starting model for 2D inversion of AMT data. Thus, the joint interpretation of the TDEM and VES curves makes the range of possible equivalent resistivity models considerably narrower and allows obtaining new and more reliable information about the resistivity structures than using each of the data of the methods separately. Involving AMT data to the interpretation allows increasing depth of investigation. |
| Session Keyword | 3.0 EM methods for exploration (geothermal, mineral resources, etc.) |
| File upload |
3.0_the_results_of_joint_em_d_aleksanova.pdf
|