Seismic imaging of magma sills beneath an ultramafic-hosted hydrothermal system

Abstract

Research Article| May 01, 2017 Seismic imaging of magma sills beneath an ultramafic-hosted hydrothermal system J. Pablo Canales; J. Pablo Canales 1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Search for other works by this author on: GSW Google Scholar Robert A. Dunn; Robert A. Dunn 2Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA Search for other works by this author on: GSW Google Scholar Ryuta Arai; Ryuta Arai 3Research and Development Center for Earthquake and Tsunami, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan Search for other works by this author on: GSW Google Scholar Robert A. Sohn Robert A. Sohn 1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Search for other works by this author on: GSW Google Scholar Author and Article Information J. Pablo Canales 1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Robert A. Dunn 2Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA Ryuta Arai 3Research and Development Center for Earthquake and Tsunami, Japan Agency for Marine-Earth Science and Technology, Yokohama, Kanagawa, Japan Robert A. Sohn 1Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Publisher: Geological Society of America Received: 12 Nov 2016 Revision Received: 21 Jan 2017 Accepted: 27 Jan 2017 First Online: 28 Jun 2017 Online Issn: 1943-2682 Print Issn: 0091-7613 © 2017 Geological Society of America Geology (2017) 45 (5): 451–454. https://doi.org/10.1130/G38795.1 Article history Received: 12 Nov 2016 Revision Received: 21 Jan 2017 Accepted: 27 Jan 2017 First Online: 28 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation J. Pablo Canales, Robert A. Dunn, Ryuta Arai, Robert A. Sohn; Seismic imaging of magma sills beneath an ultramafic-hosted hydrothermal system. Geology 2017;; 45 (5): 451–454. doi: https://doi.org/10.1130/G38795.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Hydrothermal circulation at mid-ocean ridge volcanic segments extracts heat from crustal magma bodies. However, the heat source driving hydrothermal circulation in ultramafic outcrops, where mantle rocks are exhumed in low-magma-supply environments, has remained enigmatic. Here we use a three-dimensional P-wave velocity model derived from active-source wide-angle refraction-reflection ocean bottom seismometer data and pre-stack depth-migrated images derived from multichannel seismic reflection data to investigate the internal structure of the Rainbow ultramafic massif, which is located in a non-transform discontinuity of the Mid-Atlantic Ridge. Seismic imaging reveals that the ultramafic rocks composing the Rainbow massif have been intruded by a large number of magmatic sills, distributed throughout the massif at depths of ∼2–10 km. These sills, which appear to be at varying stages of crystallization, can supply the heat needed to drive high-temperature hydrothermal circulation, and thus provide an explanation for the hydrothermal discharge observed in this ultramafic setting. Our results demonstrate that high-temperature hydrothermal systems can be driven by heat from deep-sourced magma even in exhumed ultramafic lithosphere with very low magma supply. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.