Gas Monitoring at Long Valley and the Surrounding Region
The most commonly analyzed volcanic gases are carbon dioxide (CO2) and sulfur dioxide (SO2). By monitoring the relative abundances of these gas types, scientists may be able to infer magma movement through the volcanic system. Gas monitoring can either be conducted close to the source in ground-based campaigns or from a distance using remote sensing.
Between 1988 and 1989 a large amount of CO2 was detected near the edge of Long Valley Caldera at Mammoth Mountain; the event also coincided with an earthquake swarm. The gas discharge has been responsible for a large kill-off of vegetation in the area. Read more about volcanic gas monitoring at Mammoth Mountain.