Investigating La Réunion Hot Spot From Crust to Core

• Published in: Eos, Transactions American Geophysical Union
• Main Authors: Barruol, Guilhem, Sigloch, Karin
• Other Authors: Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Laboratoire GéoSciences Réunion (LGSR), Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris), Department of Geosciences Princeton, Princeton University, Ludwig-Maximilians-Universität München (LMU)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]; Indian; Eyjafjallajökull; Iceland
• Online Access: https://hal.univ-reunion.fr/hal-01236083; https://hal.univ-reunion.fr/hal-01236083/document; https://hal.univ-reunion.fr/hal-01236083/file/Barruol_Sigloch_RHUM_RUM.pdf; https://doi.org/10.1002/2013eo230002

International audience Whether volcanic intraplate hot spots are underlain by deep mantle plumes continues to be debated 40 years after the hypothesis was proposed by Morgan [1972]. Arrivals of buoyant plume heads may have been among the most disruptive agents in Earth's history, initiating continental breakup, altering global climate , and triggering mass extinctions. Further, with the temporary shutdown of European air traffi c in 2010 caused by the eruption of Eyjafjallajökull, a geologically routine eruption in the tail end of the presumed Iceland plume, the world witnessed an intrusion of hot spot activity into modern-day life. The larger interest in intraplate hot spots stems from the suspicion that their volcanism is fueled by mantle plumes, which are deep-seated, columnar upwellings of hot rock, possibly originating from the core-mantle boundary. Depending on their numbers and typical heat fl uxes, mantle plumes could be major factors in Earth's heat budget, providing direct cooling to the core. Seismology could settle the controversy regarding their existence and signifi cance by imaging plume conduits—or lack thereof—in situ, but the most promising hot spots are located well into the oceans, and large-scale instrumentation of the seafl oor has been coming into reach only recently. In an effort to learn more about plume origins and dynamics through seismology, scientists from France and Germany are focusing on the Indian Ocean's La Réunion Island. Its close proximity to major landmasses (Madagascar and mainland Africa) allows for excellent seismic illumination, reducing the need for expensive ocean bottom sensors to record earthquakes around the globe. The Réunion Hotspot and Upper Mantle– Réunions Unterer Mantel (RHUM-RUM) project aims to seismologically image the crust and mantle under the island at all depths. Through what is thus far the most expansive attempt to work out the deep plumbing of hot spots, RHUM-RUM scientists may be able to clarify the feeding mechanism for hot spot volcanism, ...