| Autor: |
Evgeny Chuvilin, Boris Bukhanov, Dinara Davletshina, Sergey Grebenkin, Vladimir Istomin |
| Jazyk: |
angličtina |
| Rok vydání: |
2018 |
| Předmět: |
|
| Zdroj: |
Geosciences, Vol 8, Iss 12, p 431 (2018) |
| Druh dokumentu: |
article |
| ISSN: |
2076-3263 |
| DOI: |
10.3390/geosciences8120431 |
| Popis: |
Gases releasing from shallow permafrost above 150 m may contain methane produced by the dissociation of pore metastable gas hydrates, which can exist in permafrost due to self-preservation. In this study, special experiments were conducted to study the self-preservation kinetics. For this, sandy samples from gas-bearing permafrost horizons in West Siberia were first saturated with methane hydrate and frozen and then exposed to gas pressure drop below the triple-phase equilibrium in the “gas⁻gas hydrate⁻ice„ system. The experimental results showed that methane hydrate could survive for a long time in frozen soils at temperatures of −5 to −7 °C at below-equilibrium pressures, thus evidencing the self-preservation effect. The self-preservation of gas hydrates in permafrost depends on its temperature, salinity, ice content, and gas pressure. Prolonged preservation of metastable relict hydrates is possible in ice-rich sandy permafrost at −4 to −5 °C or colder, with a salinity of |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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