Earth’s Cryosphere, 2017, Vol. XXI, No. 3, p. 3-11

ELECTRICAL RESISTIVITY TOMOGRAPHY AND RADON SURVEY OF KIMBERLITE-CONTAINING FAULT ZONES ON ALAKIT-MARKHINSKY FIELD IN WESTERN YAKUTIA: PRACTICAL EXPERIENCE

K.Zh. Seminsky1, A.A. Bobrov1, V.V. Olenchenko2

1 Institute of the Earth’s Crust, SB RAS, 128, Lermontova str., Irkutsk, 664033, Russia; seminsky@crust.irk.ru
2 Trofimuk Institute of Petroleum Geology and Geophysics, SB RAS,
3, Acad. Koptuga ave., Novosibirsk, 630090, Russia; OlenchenkoVV@ipgg.sbras.ru

The experience of application of a complex of near-surface geophysical methods (electrical resistivity tomography and soil radon survey) for identification of fault zones in the platform cover of the Alakit-Markhinsky kimberlite field in Western Yakutia is presented. Surveys were carried out in the summertime on the sites of Faynshteynovsky and Baytakhsky kimberlite bodies. In total, six profiles were passed: on each site, two profiles made over the kimberlite pipe, and the third one beyond the pipe boundaries. The methods applied have been shown to supplement each other and, despite the severe conditions of realization (the high moisture content in the soil layer, permafrost, etc.), allow fault zones to be identified. The structure of the fault zones in the top part of the platform cover corresponds to the early stage of fault formation. The soil radon anomaly of a faltering character and the subvertical anomaly of increased conductivity in the geoelectric cross-section correspond to the kimberlite containing zone. The heterogeneal character of both anomalies analyzed jointly allows distinct fractures of the second order, which are concentrated in the fault zone, to be identified.

Fault zone, electrical resistivity tomography, radon, permafrost rock, kimberlite field

DOI: 10.21782/EC2541-9994-2017-3(3-11)