The eruption ended about noon on 16 April with the cessation of lava extrusion from the fissure above Piton Sainte Rose (figure 1). Maurice Krafft reports that the lava described last month as flowing towards the sea on 11 April was a small flow (11 B on figure 1) originating from a fissure in the caldera wall (Rempart de Bois Blanc) and that the extrusion of a flow from the NE quarter of the caldera on 13 April is "very contested now."

Further References. Bout, P., 1979, Observations sur les Coulees de Basalte (Oceanites) des eruptions des 9-17 Avril 1977 de Piton Sainte-Rose (Réunion): 4ème Colloque de Geomorphologie Volcaniques: Problemes du Volcanisme Explosif: Clermont-Ferrand, Univ., Fac. Lett. Inst. Geogr., v. 57, p. 47-52.

Kieffer, G., Tricot, B., and Vincent, P.M., 1977, Une eruption inhabituelle (Avril 1977) du Piton de la Fournaise (Ile de la Réunion): Ses Enseignements Volcanologiques et Structuraux: C.R. Acad. Sci. Paris, serie D, v. 285, p. 957-960.

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.

Information Contacts: M. Krafft, Ensisheim.