Mazuku

Mazuku forming in a low morphological depression on the foothills of Mt. Amiata, Italy, where CO2-rich fog accumulates in a ditch

Mazuku (Swahili for "evil winds") are pockets of dry, cold carbon dioxide-rich gases released from vents or fissures in volcanically and tectonically active areas, and mixed with dispersed atmospheric air and accumulating in typically low-lying areas.[1][2][3] Since CO2 is ~1.5[4] times heavier than air, it tends to flow downhill, hugging the ground like a low fog and gather in enclosed spaces with poor ventilation, such as lava tubes, ditches, depressions, caves, house basements or in the stratified water layers of meromictic lakes if a water column exists.[5][6][7] In high concentrations (≥1vol.%), they can pose a deadly risk to both humans and animals in the surrounding area because they are undetectable by olfactory or visual senses in most conditions.[1][3]

Mazuku primarily occur on northern shores of Lake Kivu on both sides of the twin towns of Goma in the Democratic Republic of the Congo (DRC) and Gisenyi in Rwanda where local communities in these areas use this term in their vernacular (Kinyabwisha language) to describe the evil winds.[4] They believe mazuku occur in cursed locations where invisible forces that travel unnoticed often silently kills people during the night when they are sleeping.[8][9] In many mazuku places, CO2 levels falls during daytime but can rise to a significantly dangerous concentrations levels of about 90% at night, early mornings or evening hours posing great threat.[4][8] This is because during nighttime, the atmospheric temperature drops, and wind speeds are significantly reduced.[8][10] These conditions hinder the rapid dispersal of these heavy gases into the atmosphere, allowing them to accumulate in lower-lying areas, such as valleys and depressions.[11][12][13]

  1. ^ a b Smets, Benoît; Tedesco, Dario; Kervyn, François; Kies, Antoine; Vaselli, Orlando; Yalire, Mathieu Mapendano (2010-12-01). "Dry gas vents ("mazuku") in Goma region (North-Kivu, Democratic Republic of Congo): Formation and risk assessment". Journal of African Earth Sciences. Active Volcanism and Continental Rifting in Africa. 58 (5): 787–798. Bibcode:2010JAfES..58..787S. doi:10.1016/j.jafrearsci.2010.04.008. ISSN 1464-343X.
  2. ^ Kagabo, Laurent Bizimungu; Balagizi, Charles M.; Yalire, Mathieu M.; Habamungu, Richard B.; N., Samuel Kasigwa; Rusimbuka, Marcel B.; Seza, Diane B.; Bonheur, Rugain Ngangu (2024-04-11). "War Displaced Persons Facing the Risks Associated with Mazuku In and Around the Goma City" (PDF). International Journal of Research Publication and Reviews. 5 (4): 7321–7327. doi:10.55248/gengpi.5.0424.10111.
  3. ^ a b Tedesco, D.; Tassi, F.; Vaselli, O.; Poreda, R. J.; Darrah, T.; Cuoco, E.; Yalire, M. M. (January 2010). "Gas isotopic signatures (He, C, and Ar) in the Lake Kivu region (western branch of the East African rift system): Geodynamic and volcanological implications". Journal of Geophysical Research: Solid Earth. 115 (B1). Bibcode:2010JGRB..115.1205T. doi:10.1029/2008JB006227. ISSN 0148-0227.
  4. ^ a b c Balagizi, Charles M.; Kies, Antoine; Kasereka, Marcellin M.; Tedesco, Dario; Yalire, Mathieu M.; McCausland, Wendy A. (2018-08-01). "Natural hazards in Goma and the surrounding villages, East African Rift System". Natural Hazards. 93 (1): 31–66. Bibcode:2018NatHa..93...31B. doi:10.1007/s11069-018-3288-x. ISSN 1573-0840.
  5. ^ Hirslund, F.; Morkel, P. (2020-01-01). "Managing the dangers in Lake Kivu – How and why". Journal of African Earth Sciences. 161: 103672. Bibcode:2020JAfES.16103672H. doi:10.1016/j.jafrearsci.2019.103672. ISSN 1464-343X.
  6. ^ Zana Lambadi, Aimé (2023). "Les impacts environnementaux des éruptions volcaniques dans une zone à faible taux d'exploitation technologique : cas de la province du Nord-Kivu en RD Congo" (PDF). Revista Congolaise des Sciences et Technologies (RCST). 02 (1): 280-288 (2023). doi:10.59228/rcst.023.v2.i1.30 – via Article de recherche.
  7. ^ Viveiros, Fátima; Silva, Catarina (October 2024). "Hazardous volcanic CO2 diffuse degassing areas – A systematic review on environmental impacts, health, and mitigation strategies". iScience. 27 (10): 110990. doi:10.1016/j.isci.2024.110990. ISSN 2589-0042. PMC 11490718. PMID 39429787.
  8. ^ a b c Tuttle, M. L.; Lockwood, John P.; Evans, William C. (1990). "Natural hazards associated with Lake Kivu and adjoining areas of the Birunga volcanic field, Rwanda and Zaire, Central Africa; final report". Open-File Report (Report). U.S. Geological Survey. doi:10.3133/ofr90691.
  9. ^ Le Guern, F.; Tazieff, H.; Pierret, R. Faivre (1982-06-01). "An example of health hazard: People killed by gas during a phreatic eruption: Diëng plateau (Java, Indonesia), February 20th 1979". Bulletin Volcanologique. 45 (2): 153–156. Bibcode:1982BVol...45..153L. doi:10.1007/BF02600430. ISSN 1432-0819.
  10. ^ van Gardingen, Paul R.; Grace, John; Harkness, Douglas D.; Miglietta, Franco; Raschi, Antonio (1995-02-01). "Carbon dioxide emissions at an Italian mineral spring: measurements of average CO2 concentration and air temperature". Agricultural and Forest Meteorology. 73 (1): 17–27. doi:10.1016/0168-1923(94)02176-K. ISSN 0168-1923.
  11. ^ Rogie, John D; Kerrick, Derrill M; Sorey, Michael L; Chiodini, Giovanni; Galloway, Devin L (June 2001). "Dynamics of carbon dioxide emission at Mammoth Mountain, California". Earth and Planetary Science Letters. 188 (3–4): 535–541. Bibcode:2001E&PSL.188..535R. doi:10.1016/S0012-821X(01)00344-2.
  12. ^ Vaselli, Orlando (January 2003). "The "evil winds" (mazukus) at Nyiragongo volcano (Democratic Republic of Congo)". Acta Vulcanologica. 14–15.
  13. ^ Viveiros, Fátima; Gaspar, João L.; Ferreira, Teresa; Silva, Catarina (July 2016). "Hazardous indoor CO2 concentrations in volcanic environments". Environmental Pollution. 214: 776–786. Bibcode:2016EPoll.214..776V. doi:10.1016/j.envpol.2016.04.086. PMID 27155095.