Volcaniclastic sedimentation on the submarine slopes of a basaltic hotspot volcano: Piton de la Fournaise volcano (La Réunion Island, Indian Ocean)
|Author(s)||Saint-Ange Francky1, 2, 4, Bachelery Patrick3, 4, Babonneau Nathalie5, Michon Laurent4, Jorry Stephan6|
|Affiliation(s)||1 : Geol Survey Canada Atlantic, Bedford Inst Oceanog, Dartmouth, NS B2Y 4A2, Canada.
2 : Dalhousie Univ, Dept Oceanog, Halifax, NS B3H 4J1, Canada.
3 : Univ Clermont Ferrand, Lab Magmas & Volcans, UMR 6524, CNRS, Clermont Ferrand, France.
4 : Univ Reunion, Lab Geosci Reunion, Inst Phys Globe Paris, CNRS,UMR 7154, F-97715 St Denis 9, France.
5 : Univ Brest, CNRS UMR Domaines Ocean 6538, IUEM, F-29280 Plouzane, France.
6 : IFREMER, Geosci Marines, Lab Environm Sedimentaires, F-29280 Plouzane, France.
|Source||Marine Geology (0025-3227) (Elsevier Science Bv), 2013-03 , Vol. 337 , P. 35-52|
|WOS© Times Cited||19|
|Keyword(s)||turbidites, debris avalanche, landslide, erosion, volcano, La Reunion Island|
|Abstract||Volcaniclastic successions are well-described in volcanic arc setting but rare in hotspot environments. The present work proposes a facies model of volcaniclastic sedimentation related to basaltic hotspot volcanoes as exemplified by the Piton de la Fournaise volcano (La Réunion Island). The facies model is based on a multi-scale approach combining high-resolution multibeam and backscatter data, deep-water photographs, side scan imagery and Kullenberg piston cores. Data show that a wide range of gravity flows and erosional features develop in the active volcaniclastic sedimentary system. Coastal and submarine instabilities are the main processes shaping the volcano's submarine morphology. Meanwhile, the evolution and dynamics of the sedimentary system are strongly linked with the morpho-structural evolution of the subaerial part of the volcano. The proposed model is characterized by a cyclic succession of stages: (1) a growing stage during which sedimentary activity is mainly restricted to proximal and mid-slope areas; (2) a collapse stage that entirely reshapes the morphology of the submarine slopes; and (3) an erosional stage related to a slow down of volcanic activity, enabling the development of large deep-sea fans.|