Modeling thermal regime and evolution of the methane hydrate stability zone of the Yamal peninsula permafrost

• Published in: Permafrost and Periglacial Processes
• Main Authors: Arzhanov, Maxim M., Malakhova, Valentina V., Mokhov, Igor I.
• Other Authors: Russian Foundation for Basic Research, Russian Science Foundation
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2020
• Subjects: Methane hydrate; permafrost; Permafrost and Periglacial Processes; Yamal Peninsula; Siberia
• Online Access: http://dx.doi.org/10.1002/ppp.2074; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fppp.2074; https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.2074; https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ppp.2074

Abstract In recent years, new geophysical phenomena have been observed in the high‐latitude regions of continental permafrost. Since 2014 new craters 10–20 m in diameter have been found within the Yamal Peninsula and neighboring regions. They are associated with the emissions of gases, which could have been formed during dissociation of relict gas hydrate deposits due to increases in soil temperature. This paper presents the results of numerical modeling of the thermal regime of permafrost in the north of Western Siberia with the assessment of methane hydrate stability zone under climate changes over the past 130,000 years. According to the results obtained, the upper boundary of the methane hydrate stability zone in Yamal could have reached the surface within the periods of glacial maxima (about 90,000 and 60,000 years ago). We show that at present in Yamal permafrost above the modern boundary of the stability zone, relic methane hydrates are likely to exist at depths of up to 100–150 m, they could have “survives” warming during the Holocene optimum about 6,000 years ago and remain in permafrost rocks under negative temperatures even under transgression and increased geothermal flux conditions.