GEOCHEMICAL PROSPECTING FOR OIL‐AND GASFIELDS IN THE NE USSR (CIS)†

• Published in: Journal of Petroleum Geology
• Main Author: Glotov, V. E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1992
• Subjects: Earth and Planetary Sciences (miscellaneous); Geology; Energy Engineering and Power Technology; Fuel Technology; Anadyr; Anadyr'; permafrost; Tundra
• Online Access: http://dx.doi.org/10.1111/j.1747-5457.1992.tb00877.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1747-5457.1992.tb00877.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1747-5457.1992.tb00877.x

The NE USSR is an area of great interest for oil and gas exploration. Geochemical prospecting methods are particularly useful in areas of permafrost, and the efficiency of these methods has been established by tests in the Anadyr and Khatyrka Basins. This paper presents data on the spatial and temporal changes in the content of methane and its gaseous homologues in seasonally‐thawed soil layers, near‐surface air and lichens. Annual freezing and thawing of the near‐surface layers has been shown to result in various geochemical processes which were previously unknown. When near‐surface layers are frozen in Winter, gases migrating upwards from the Earth's interior accumulate within them. During warmer weather in Spring, the accumulated gases diffuse into the atmosphere, and the hydrocarbons content of the near‐surface air is then tens or hundreds of times higher than at the end of Summer. Evidence has been obtained of regular alterations in methane contents. The intensity of solar radiation has been proved to influence the diurnal methane content of the atmosphere. Lichens are accepted to be accurate indices of hydrocarbon pollution at the Earth's surface. The distribution of hydrocarbon‐oxidising bacteria in tundra is described, and methods of geochemical prospecting are evaluated.