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The detailed TEM sounding plus utilization of digital telemetric systems are assigned to detect contrast anomalies of geoelectric parameters within a wide spectrum of depths through differentiated section. Monitoring is relevant in defining the ways of fluid migration through formation-reservoir, as well as in searching zones of anomalously high formation pressures or absorbing sections in drilling wells. The assignments posed have been successfully executed by TEM at the Kovykta gas-condensate field, where the well drilling operations are considerably complicated by local geological conditions. The 3D-simulation was performed through a real grid to measure rise of reservoir conductivity at different sizes of fields. Having defined absorbing sections or using the AHFP methods of electric survey it is feasible to select the most favorable sites for placing deep wells, where the crust section is fairly homogeneous, and it has no high-conductivity horizons. This approach essentially facilitates drilling operations; it helps to minimize the accident/breakdown risk, and consequently to avoid expenditures.
Besides, the TEM-based monitoring is performed in investigation of sedimentary cover at large industrial sites, where technological interaction occurs intensely in the system environment– horizons-reservoirs (sources of commodities) – production – reservoirs of recycling. The effective mathematical algorithms of man-made noise suppression ensure gaining relevant geophysical stuff even in the vicinity of noise sources, e.g. electric mains, Diesel units, etc. The efficiency of TEM method in defining directions of industrial waste propagation in the reservoirs of supra-salt and halogen-carbonate complex was proved by the works at the large chemical combine of Irkutsk Region. The results of monitoring were used in constructing maps of resistivity and conductivity of cross-section by comparing them with formerly acquired data; the aureoles of fluid propagation and direction of migration have been defined as well.
The scope of assignments implemented by monitoring with TEM is quite broad. A high efficiency of the method depends on utilization of the present-day telemetric facility SGS-TEM, which lets electric prospecting to be conducted at a high space-time density, as well as electromagnetic noise to be removed. This circumstance favors fulfilling geological assignments in any geological setting at a high performance rate and quality.
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