HR: 0800h
AN: V41B-0593    [Abstracts]
TI: Bromine, chlorine and sulfur emission into the free troposphere from a Rift volcano
AU: * Bobrowski, N
EM: n.bobrowski@pa.ingv.it
AF: INGV Sezione di Palermo, Via Ugo la Malfa 153, Palermo, 90146, Italy
AU: Giuffrida, G B
EM: g.giuffrida@pa.ingv.it
AF: INGV Sezione di Palermo, Via Ugo la Malfa 153, Palermo, 90146, Italy
AU: Tedeso, D
EM: dtedesco@unina.it
AF: University Napoli, Via Vivaldi 43, Casserta, 81100, Italy
AU: Yalire, M M
EM: yaliremat@yahoo.fr
AF: Observatoire Volcanologique de Goma, SOUTH KIVU, Goma, 00000, Congo, The Democratic Republic of the
AU: Galle, B
EM: bo.galle@rss.chalmers.se
AF: Chalmers University of Technology, Department of Radio and Space Science, Hörsalsvägen 11, Göteborg, 412 96, Sweden
AB: In June 2007 spectroscopic measurements were carried out at the crater rim of the Niyragongo volcano located 15 km north of the city Goma, North Kivu region (DRC). Niyragongo volcano belongs to the Virunga volcanic chain and it is associated with the Western branch of the Great Rift Valley. The volcanism at Niyragongo is caused by the rifting of the Earth's crust where two parts of the African plates are breaking apart. Niyragongo is a 3470 m high stratovolcano, which a large summit crater usually containing a lava lake inside and it is considered one of the most active volcanoes in Africa. Satellite measurements show an extremely large sulphur dioxide plume since May 2002, and it is considered one of the biggest sulphur dioxide sources on Earth. The ground - based remote sensing technique - MAX-DOAS (Multi Axis Differential Optical Absorption Spectroscopy) using scattered sunlight has been applied during a one week field trip on top of the crater rim of Niyragongo volcano to measure nitrogen oxide, halogen oxides and sulphur dioxide. The used Mini-MAX-DOAS is a lightweight, compact, robust instrument and has very low power consumption which allows to be deployed over several days with some small lead batteries. The measurements provide valuable information of the chemical composition as well its variability within the volcanic plume of the lava lake and allowed also studying chemical transformation processes of the halogens inside the plume. Bromine-sulphur and chlorine-sulphur ratios were investigated and a minimal bromine and chlorine emission flux estimation will be presented.
DE: 8409 Atmospheric effects (0370)
DE: 8430 Volcanic gases
DE: 8485 Remote sensing of volcanoes
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting