| Abstract: | We collected a time series of physical and chemical data to gain a better understanding of the dynamics of Lake Nyos. Measurements of water and gas chemistry, and temperature made during January, March, and May 1987 are compared to data taken in September 1986 just after the initial CO2 gas release. There is no pattern of change in overall heat content of the lake, although heat input to bottom waters (185-208 m) has occurred at a rate of 1600 mW m-2. This increase in heat content translates to a change from 23.38 to 24.12??C at 200 m and can be explained by geothermal heat flow and addition of thermal spring water. Concentrations of Ca2+, Mg2+, Na+, K+, Fe2+ and alkalinity have increased only in bottom waters. In situ lake processes such as sulfate and iron reduction are unable to account for the changes in alkalinity. Observed chemical changes are consistent with a scenario where slightly thermal soda water is being input to the bottom of the lake. Measurements of pCO2 at depth ranged from 18 to 28% of saturation and exhibited horizontal variability. Overall recharge of CO2 in bottom waters is negligible. Mainly because of increasing ion concentrations in bottom water, total stability of the water column increased 33% from 48,800 J m-2 in September 1986 to 64,700 J m-2 in May 1987. As long as CO2 concentrations remain the same, this level of stability is higher than could be disrupted by common limnologic or meteorologic processes. There is thermal and chemical evidence that a buildup of dissolved iron and CO2 in bottom waters must have preceded the August 1986 gas release. In addition, a survey of all crater lakes in Cameroon indicates that only Lakes Nyos and Monoun contain high concentrations of dissolved iron and CO2. Thus there is a low probability of any other Cameroonian lake releasing a substantial volume of CO2. ?? 1989. |
| Genre: | Article |
| ProdID: | 70015510 |
| Citation Author: | Kling, G. W.; Tuttle, M. L.; Evans, W. C. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 165 |
| Citation Issue: | 2-3 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Journal of Volcanology and Geothermal Research |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 15 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | The evolution of thermal structure and water chemistry in Lake Nyos; 1989; Article; Journal; Journal of Volcanology and Geothermal Research; Kling, G. W.; Tuttle, M. L.; Evans, W. C. |
| Citation Start Page: | 151 |
| Citation Volume: | 39 |
| Citation Year: | 1989 |
| Type: | citation/reference |
| Text: | The evolution of thermal structure and water chemistry in Lake Nyos; 1989; Article; Journal; Journal of Volcanology and Geothermal Research; Kling, G. W.; Tuttle, M. L.; Evans, W. C. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Sun, 1 Jan 1989 00:00 -0600 |
| Publisher: | |