THE DEGASSING OF THE LAKE MONOUN.


Results of degassing :

Monitoring of the degassing of the lake begins with the analysis of the vertical distribution of the temperature and conductivity of the waters. CTD profiles (Conductivity, Temperature, Depth) are taken approximately every 3 months by technicians from the Cameroon IRGM.

These profiles are reproduced on the diagram opposite.


Notice that the representative temperature and conductivity curves undergo a downward vertical transfer while the speed stays more or less the same. This signifies that the degassing process does not disturb, or disturbs very little, the horizontal stratification of the water.
The explanation of the speed of these curves is very simple.
The degassing columns take the water rich in dissolved gas from 92 meters and expel it at the lake surface, letting the gas escape into the atmosphere. This mechanism results in a simple subsidence (a vertical descent) of all the lake’s layers of water. Thus today (October 2006), the most dangerous layer, formerly at a depth of 54 metres is now to be found at 72 metres. The risk of a new gas explosion is thus now almost non existant.