SOME GEOELECTRIC FEATURES OF THE YAMAL PENINSULA CRYOSPHERE AND THEIR RELATIONSHIP WITH FROST mounds
I.K. Seminsky1,2, E.V. Murzina1, Yu.A. Agafonov1
1SIGMA-GEO, Irkutsk, Russia
2Institute of Solar-Terrestrial Physics, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia
Keywords: frost mound, inductively induced polarization, transient electromagnetic method, gas, permafrost, fluid migration channel, Yamal
Abstract
A key feature of the upper part of geological sections in the Arctic is the presence of permafrost, with which a number of cryogenic phenomena - thermokarst, frost mounds, gas-emission craters, etc. - are associated. These phenomena represent significant geohazards potentially causing large-scale negative consequences in the context of the actively developing oil and gas infrastructure. of the region. In this paper, some results from the interpretation of high-density shallow (up to 500 m) transient electromagnetic method data obtained in the eastern part of the Yamal Peninsula to identify fluid migration channels, which may be associated with the formation of frost mounds. It has been established that the distribution of frost mounds in the study area correlates with anomalies in polarizability and electrical resistivity. The layer of rocks, above which pingo-like landforms are found, is associated with the manifestation of inductively induced polarization likely characteristic of sediments with the low ice content, In the underlying strata, anomalies of reduced resistivity are noted, which may be associated with fluid migration channels and accumulations of gaseous hydrocarbons in the permafrost.
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