First measurements of magmatic gas composition and fluxes during an eruption (October 2010) of Piton de la Fournaise hot spot volcano, La reunion island

Piton de la Fournaise (PdF), in the western Indian Ocean, is a very active hot spot basaltic volcano, with 1-2 fissure eruptions per year on average. Its magmas have been widely studied and its eruptions are well anticipated by the local seismic-geodetic monitoring network. However, no datum was yet available for its magmatic gas emissions (restricted to only eruptive phases and hardly accessible). Here we report on the first measurements of the chemical composition and mass flux of magmatic gases emitted during a PdF eruption in October 2010. Hot gases arising from different eruptive vents were remotely measured with OP-FTIR spectroscopy, using molten lava fragments as IR radiation source,…