Institute of Mining, Far East Branch, Russian Academy of Sciences, Khabarovsk, Russia:

N. G. Shkabarnya, Head of Laboratory, Doctor of Engineering Sciences
I. Yu. Rasskazov, Director, Doctor of Engineering Sciences

Il’ichev Pacific Oceanological Institute, Far East Branch, Russian Academy of Sciences, Vladivostok, Russia:
G. N. Shkabarnya, Leading Researcher, Candidate of Engineering Sciences, shkabarnya@mail.ru

Coal fields in the Far East of Russia feature difficult geological conditions due to: occurrence of coal beds and host rocks at an incline up to 25° toward mined-out area; high head of groundwater from lower-lying unaccessed coal beds which are weak and have loose interfaces; presence of watered sandand-gravel and pebble-in-gravel deposits; multitude of tectonic faults and various discontinuities in the form of joints, nodules and snake-stones; sporadic permafrost. The studies of the geological conditions reveal low efficiency of the current electrical prospecting methods, namely, electrical sounding and profiling. This article demonstrates higher efficiency of electrical resistivity tomography in solution of separate geological problems. Under conditions of weak differentiation of rocks with respect to electrical resistance, the method of electrical resistivity tomography is advantageous owing to high density of obtained in-field parameters and automated interpretation of field data. Using this method, coal outcrops under the Quaternary deposits and tectonic faults are detected, and structure of sliding slopes of coal pit walls is determined. Successful results are obtained in tracing the weathered layer of basement rocks, sandstone outshots under soil cover at the top of pit walls, basement rocksand effusive rocks in the wings and on the surface of lignite fields in Primorye. The reliable information on faulting, behavior of coal beds, structure of sliding slopes as well as on outshots of sandstone and effusive rocks will greatly improve mining efficiency.

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