Continuous gas monitoring at Galeras Volcano, Colombia: first evidence

This paper describes a system of instruments for continuously monitoring fumarolic gases which is installed at Galeras Volcano, Colombia. Several parameters such as the concentration of CO2 and Rn in the fumarolic emissions, as well as the temperature of the gases and their pressure are measured every 6 s. We report variations in these parameters which were observed during a short flurry of seismic activity at the volcano. At this stage, it is uncertain whether the changes in the parameters are directly associated with volcanic processes. From the data presented here, we can conclude that ambient air can enter the fumarolic vent system. In consequence, the fumarole may be influenced by the direction and strength of the wind.