title: Tungsten-182 heterogeneity in modern ocean island basalts.
abstract: New tungsten isotope data for modern ocean island basalts (OIB) from Hawaii, Samoa, and Iceland reveal variable182W/184W, ranging from that of the ambient upper mantle to ratios as much as 18 parts per million lower. The tungsten isotopic data negatively correlate with3He/4He. These data indicate that each OIB system accesses domains within Earth that formed within the first 60 million years of solar system history. Combined isotopic and chemical characteristics projected for these ancient domains indicate that they contain metal and are repositories of noble gases. We suggest that the most likely source candidates are mega-ultralow-velocity zones, which lie beneath Hawaii, Samoa, and Iceland but not beneath hot spots whose OIB yield normal182W and homogeneously low3He/4He.
authors.affiliation: Department of Geology, University of Maryland, College Park, MD 20742, USA. amundl@umd.edu.
authors.forename: Andrea
authors.identifier: 0000-0001-7609-9607
authors.initials: A
authors.lastname: Mundl
authors.affiliation: Ecole Normale Supérieure de Lyon, 69364 Lyon Cedex 7, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Touboul
authors.affiliation: Department of Earth Science, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Jackson
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: James M D
authors.identifier: 0000-0001-9520-3465
authors.initials: JM
authors.lastname: Day
authors.affiliation: Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Kurz
authors.affiliation: Department of Geology, University of Maryland, College Park, MD 20742, USA.
authors.forename: Vedran
authors.identifier: 0000-0002-3548-272X
authors.initials: V
authors.lastname: Lekic
authors.affiliation: U.S. Geological Survey, Reston, VA 20192, USA.
authors.forename: Rosalind T
authors.identifier: 0000-0003-1550-0684
authors.initials: RT
authors.lastname: Helz
authors.affiliation: Department of Geology, University of Maryland, College Park, MD 20742, USA.
authors.forename: Richard J
authors.identifier: 0000-0003-0348-2407
authors.initials: RJ
authors.lastname: Walker