1. Seafloor evidence for pre-shield volcanism above the Tristan da Cunha mantle plume
- Author
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Anne Strack, Wilfried Jokat, Wolfram Geissler, Graeme Eagles, Janina Kammann, Marion Jegen, Paul Wintersteller, Marcia Maia, Antje Schloemer, Alfred Wegener Institute for Polar and Marine Research (AWI), Faculty of Geosciences, University of Bremen, Center for Marine Environmental Sciences [Bremen] (MARUM), Universität Bremen, Laboratoire Géosciences Océan (LGO), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Geoscience and Natural Resource Management, København Universitet, Danmark, Helmholtz Centre for Ocean Research [Kiel] (GEOMAR), Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universität, Ludwig-Maximilians-Universität München (LMU), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010504 meteorology & atmospheric sciences ,[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] ,Science ,Seamount ,General Physics and Astronomy ,Volcanology ,010502 geochemistry & geophysics ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Mantle plume ,Article ,Paleontology ,14. Life underwater ,lcsh:Science ,Submarine volcano ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Tectonics ,Fracture zone ,Geology ,General Chemistry ,Seafloor spreading ,Oceanic core complex ,Submarine eruption ,Geophysics ,Volcano ,13. Climate action ,lcsh:Q - Abstract
Tristan da Cunha is assumed to be the youngest subaerial expression of the Walvis Ridge hot spot. Based on new hydroacoustic data, we propose that the most recent hot spot volcanic activity occurs west of the island. We surveyed relatively young intraplate volcanic fields and scattered, probably monogenetic, submarine volcanoes with multibeam echosounders and sub-bottom profilers. Structural and zonal GIS analysis of bathymetric and backscatter results, based on habitat mapping algorithms to discriminate seafloor features, revealed numerous previously-unknown volcanic structures. South of Tristan da Cunha, we discovered two large seamounts. One of them, Isolde Seamount, is most likely the source of a 2004 submarine eruption known from a pumice stranding event and seismological analysis. An oceanic core complex, identified at the intersection of the Tristan da Cunha Transform and Fracture Zone System with the Mid-Atlantic Ridge, might indicate reduced magma supply and, therefore, weak plume-ridge interaction at present times., Here, the authors combine bathymetry and sediment echosound data to present a submarine, volcanic map of the Tristan de la Cunha region. They find that the youngest volcanic expression of the Tristan de la Cunha mantle plume is currently located to the (south-) west of the island.
- Published
- 2019
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