Quantification of the gas mass emitted during single explosions on Stromboli with the SO_2 imaging camera

摘要

We performed measurements using an SO_2 imaging camera of the SO_2 gas mass emitted during five discrete explosive events on Stromboli volcano on 3 October 2006. The SO_2 gas mass released during discrete explosions was 15-40 kg per explosion, producing 3-8% of the total daily SO_2 gas emission, demonstrating that in terms of gas flux Strombolian explosions are a second-order phenomenon compared with quiescent degassing. Using the typical gas composition measured with 0P-FT1R allows us to determine the total gas mass released during an explosion as 360-960 kg with a volume of 1500-4100 m~3 at 1 bar. At the probable source pressure of gas slug formation of 75 MPa this gas amount would occupy a volume equivalent to a sphere with a radius of 0.8-1 m, comparable with estimates of Stromboli's conduit geometry.