OVPF reported that a seismic crisis at Piton de la Fournaise began at 0603 on 11 June and was accompanied by rapid deformation. Tremor began at 0635, indicating an eruption, though inclement weather conditions prevented visual confirmation; a gas plume was recorded in webcam images. Scientists observed the eruption during a field visit around 0930, describing at least five active fissures on the SSE flank of Dolomieu Crater. Weather conditions continued to hinder visual observations. Three fissures at relatively lower elevations produced 30-m-high lava fountains and lava flows. Two higher-elevation fissures were no longer active. By 1530 only the lowest-elevation fissure remained active.

Geological Summary. Piton de la Fournaise is a massive basaltic shield volcano on the French island of Réunion in the western Indian Ocean. Much of its more than 530,000-year history overlapped with eruptions of the deeply dissected Piton des Neiges shield volcano to the NW. Three scarps formed at about 250,000, 65,000, and less than 5,000 years ago by progressive eastward slumping, leaving caldera-sized embayments open to the E and SE. Numerous pyroclastic cones are present on the floor of the scarps and their outer flanks. Most recorded eruptions have originated from the summit and flanks of Dolomieu, a 400-m-high lava shield that has grown within the youngest scarp, which is about 9 km wide and about 13 km from the western wall to the ocean on the E side. More than 150 eruptions, most of which have produced fluid basaltic lava flows, have occurred since the 17th century. Only six eruptions, in 1708, 1774, 1776, 1800, 1977, and 1986, have originated from fissures outside the scarps.

Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)