The Observatoire Volcanologique du Piton de la Fournaise reported a sharp rise in sulphur dioxide emissions from Piton de la Fournaise, a shield volcano which forms much of the eastern part of Réunion Island, an island in the western Indian Ocean which forms a department of France, on 3 May 2015, followed by a similar rise in hydrogen sulphide emissions on 5 May. From 4 May onwards a rise in Earthquake activity beneath the mountain, which often signifies magma moving through chambers beneath a volcano, was detected, combined with inflation of the base of the summit cone. This seismic activity climbed steadily till 17 May, when about 200 events were recorded over a period of about 90 minutes, between 11.00 am local time and 12.30 pm. A second burst of intense seismic activity began at about 12.50 pm, followed by an eruption from a new fissure to the southeast of Dolomieu Crater. A total of three new fissures were detected in the area that afternoon, all producing lava fountains, and tw lava flows were also observed, and a gas plume which rose about 4 km over the summit of the volcano and drifted to the northwest. The most westerly of the new fissures stopped emitting lava before midnight, and by morning on 18 may only a single fissure was active, producing a lava fountain reaching 40-50 m in height and a flow that travelled 4 km from the opening, as well as a smaller gas plume, with a high hydrogen sulphide and carbon dioxide content. On 19 May the fissure activity had subsided, with fountains reaching at most 20-30 m in height, and the lava flow proceeding only another 750 m during the day.
Categories: Earthquake; France; Hotspot Volcanism; Indian Ocean; Lava Flows; Piton de la Fournaise; Réunion Hotspot; Réunion Island; Volcano; Vulcanology;