Cameroon

LAKES NYOS AND MONOUN, CAMEROON

These two lakes released large clouds of CO₂ gas in the 1980’s, killing nearly two thousand people. The events offer dramatic evidence of the power of cold groundwater to hold magmatic CO₂ in solution. Groundwater circulating in the diatreme underlying these crater lakes absorbed magmatic CO₂ and carried it up into the lake’s bottom layers. An overturn of the water column allowed the gas to come out of solution rapidly and catastrophically. All of the chemical data collected at these lakes is posted on a web site (Cameroon Lakes), maintained at the University of Michigan.

The initial degassing phase of Nyos-Monoun-Degassing-Project (NMDP) began at Lake Nyos in January 2001. A remotely controlled degassing system was installed, and degassing was successfully tested on 30 January. Permanent, automatic operation commenced ~2 months later. This system will offset any further increase of CO₂ in the lake, resulting in reduction of the risk of another gas explosion. In addition an early warning system for gas detection was set up at both Lakes Monoun and Nyos. Tthe system automatically produces a warning to the local people by sounding a siren and flashing a red light. 

Publications
Sigurdsson, Haraldur, Devine, J.D., Tchoua, F. M., Presser, T. S., Pringle, M. K. W., and Evans, W. C., 1987, Origin of the lethal gas burst from Lake Monoun, Cameroon: J. Volcanol. Geotherm. Res., 31, 1-16.

Kling, G. W., Clark, M. A., Compton, H. R., Devine, J. D., Evans, W. C., Humphrey, A. M., Koenigsberg, E.J., Lockwood, J. P., Tuttle, M. L., and Wagner, G. N., 1987, The 1986 Lake Nyos gas disaster in Cameroon, West Africa: Science, v. 236, pp. 169-175.

Evans, W. C., G. W. Kling, M. L. Tuttle, G. Tanyileke, and L. D. White. 1993. Gas buildup in Lake Nyos: the recharge process and its consequences. Applied Geochemistry 8:207-221.

Kling, G. W., Evans, W. C., Tuttle, M. L. and Tanyileke, G., 1994, Forecasting the chemical evolution of gas-rich lakes: Equilibrium, gas bursts, or controlled degassing: Nature, v. 368, p. 405-406.

Evans, W. C., White, L. D., Tuttle, M. L., Kling, G. W., Tanyileke, G., and Michel, R. L., 1994, Six years of change at Lake Nyos, Cameroon, yield clues to the past and cautions for the future: Geochemical Journal, v. 28, p. 139-162.

links
University of Michigan pages on lakes Monoun and Nyos

Centre de Recherches Volcanologiques (CNRS) pages on lakes Monoun and Nyos

Smithsonian Magazine articlle on "Defusing Africa's Killer Lakes"

 

Contact: Bill Evans