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Measuring volcanic gases with a Fourier transform infrared (FTIR) s...

Detailed Description

Since the opening of the Overlook vent in Halema‘uma‘u Crater in 2008, FTIR spectroscopy has been used to monitor summit eruptive-gas composition. Infrared energy emitted by the lava lake surface (top left) is absorbed by gases present in the path between the instrument and the lak surface. Absorption is proportional to the concentration of each type of gas that are present in the path, including H2O, SO2,CO2, HCL, HF, and CO.

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