Assesment of the risk of degazation of the Black Sea: type of limnological disaster on lake Nyos reconsidered

Cover Page

Cite item

Full Text

Abstract

The possibility of a repetition of the limnological catastrophe in the Black Sea is considered. It is shown that, in contrast to the volcanic lakes of Africa Nyos and Manun, where limnological catastrophes occurred in the 1980s, the concentration of dissolved gases in deep waters is significantly less than the saturation value. This eliminates the mechanism of so called “eruption” of carbon dioxide such as gas lift. However, on a smaller scale, significant methane releases are possible during strong eruptions of underwater mud volcanoes. The mechanism for the release of carbon dioxide from the lake into the atmosphere is so similar to a volcanic eruption that mathematical models developed for ordinary volcanoes are used to describe it. In both cases, the rise of erupted masses occurs due to an increase in the buoyancy of the gas-liquid mixture, which carries with it particles of the environment. The formation and growth of gas bubbles at intermediate depths occurs provided that the total partial pressure of all gases inside the bubble exceeds the hydrostatic pressure at a given depth. The article shows that the concentration of dissolved methane in the Black Sea is much less than the saturation level. Due to the relatively low solubility of methane in water, methane bubbles are able to overcome a significant depth range. And as additional components of the gas mixture, together with methane, carbon dioxide and hydrogen sulfide can thus enter the atmosphere. It was concluded that as the water temperature in the Black Sea increases due to climate change, the reserves of methane gas hydrate at the bottom of the sea will begin to decompose, which will also be accompanied by jet gas release. At the same time, methane can escape to the surface from depths of no more than 900 m.

References

  1. Артемов Ю.Г., Егоров В.Н., Гулин С.Б., Поликарпов Г.Г. Новые каналы струйной разгрузки метана во впадине Сорокина в глубоководной части Черного моря // Морской экологический журнал. – 2013. – Т.12, № 4. – С. 27-36.
  2. Бондаренко Д.Д., Ершов В.В. Газогеохимия грязевых вулканов в связи с прогнозом нефтегазоносности земных недр // Известия ВУЗов. Северо-Кавказский регион. Естественные науки. – 2019. – №2. – С. 41-46.
  3. Дегтерев А.Х. Влияние гидратообразования на проявление свободных газовых выходов метана на дне водоемов // Геология и геофизика-2017, Т.58, № 9. – С. 1388-1393.
  4. Краснова Е.Д. Экология меромиктических озер России. 1. Прибрежные морские водоемы // Водные ресурсы. – 2021. – Т.48, № 3. – С. 323-333.
  5. Лосюк Г.Н., Кокрятская Н.М., Краснова Е.Д. Сероводороное заражение прибрежных озер на разных стадиях изоляции от Белого моря // Океанология. – 2021. – Т.61, № 3. – С. 401-412.
  6. Решетняк О.С., Никаноров А.М. Гидрохимия и охрана водных ресурсов. – Ростов-на Дону: Изд.ЮФУ, 2018. – 134 с.
  7. Шнюков Е.Ф. Грязевые вулканы Черного моря как поисковый признак газогидратов метана // Литология и полезные ископаемые. – 2013. – № 2. – С. 114-121.
  8. Шнюков Е.Ф., Пасынков А.А., Любицкий А.А. и др. Грязевые вулканы на прикерченском участке шельфа и материкового склона Черного моря // Геология и полезные ископаемые Мирового океана. – 2010. – № 3. – С. 28-36.
  9. Barrenbold F., Boehrer B., Grilli R., Mugisha A. No increasing risk of limnic eruption at lake Kivu: Intercomparision stady reveals gas concentrations close to steady state // PLoS ONE. – 2020. – N 8. – P. 1-14.
  10. Duan Z., Sun R. An improved model calculating CO2 solibility in pure water and aqueous NaCl solutions from 273 to 533 K and from 0 to 2000 bar // Chemical Geology. – 2003. – 193. – P. 257-271.
  11. Folch A., Barcons J., Kozono T., Costa A. High-resolution modelling of atmospheric dispersion of dense gas using TWODEE-2.1: application to the 1986 Lake Nyos limnic eruption // Natural Hazards and Earth system Sciences. – 2017. – Vol.17 (6). – P. 861-879.
  12. Kling G.W., Evans W.C., Tuttle M.L. A comparative view of Lake Nyos and Monoun, Cameroon, West Africa // Internationale Vereinigang fur theoretische und angewandle Limnologie: Verhandlungen. – 1991, December. – P. 1102-1105.
  13. Kozono T., Kusakabe M., Yoshida Y. et al. Numerical assessment of the potential for future limnic eruptions at lakes Nyos and Monoun, Cameroon, based on regular monitoring data // Geological Society London Special Publication. – 2016, January. – P. 1-14.
  14. Manirambona E., Aaebisi J.A., Lucero-Prisno III.E. Volcanic and limnic eruption: a potential threat to one health // PAMJ – One Health. – 2021. – 6(6). – P. 1-5.
  15. Zhang Y. Dynamics of CO2 – driven lake eruptions // Letters to Nature. – 1996. – Vol. 379. – P. 1-3.

Supplementary files

Supplementary Files
Action
1. JATS XML
Download

Согласие на обработку персональных данных

 

Используя сайт https://journals.rcsi.science, я (далее – «Пользователь» или «Субъект персональных данных») даю согласие на обработку персональных данных на этом сайте (текст Согласия) и на обработку персональных данных с помощью сервиса «Яндекс.Метрика» (текст Согласия).