Ultrafine-scale magnetostratigraphy of marine ferromanganese crust

Abstract

Research Article| March 01, 2011 Ultrafine-scale magnetostratigraphy of marine ferromanganese crust Hirokuni Oda; Hirokuni Oda 1Geological Survey of Japan, AIST (National Institute of Advanced Industrial Science and Technology), Central 7, 1-1-1 Higashi, Tsukuba 305-8567, Japan Search for other works by this author on: GSW Google Scholar Akira Usui; Akira Usui 2Kochi University, 2-5-1 Akebono, Kochi 780-8520, Japan Search for other works by this author on: GSW Google Scholar Isoji Miyagi; Isoji Miyagi 1Geological Survey of Japan, AIST (National Institute of Advanced Industrial Science and Technology), Central 7, 1-1-1 Higashi, Tsukuba 305-8567, Japan Search for other works by this author on: GSW Google Scholar Masato Joshima; Masato Joshima 1Geological Survey of Japan, AIST (National Institute of Advanced Industrial Science and Technology), Central 7, 1-1-1 Higashi, Tsukuba 305-8567, Japan Search for other works by this author on: GSW Google Scholar Benjamin P. Weiss; Benjamin P. Weiss 3Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA Search for other works by this author on: GSW Google Scholar Chris Shantz; Chris Shantz 3Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA Search for other works by this author on: GSW Google Scholar Luis E. Fong; Luis E. Fong 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Search for other works by this author on: GSW Google Scholar Krista K. McBride; Krista K. McBride 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Search for other works by this author on: GSW Google Scholar Rene Harder; Rene Harder 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Search for other works by this author on: GSW Google Scholar Franz J. Baudenbacher Franz J. Baudenbacher 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Hirokuni Oda 1Geological Survey of Japan, AIST (National Institute of Advanced Industrial Science and Technology), Central 7, 1-1-1 Higashi, Tsukuba 305-8567, Japan Akira Usui 2Kochi University, 2-5-1 Akebono, Kochi 780-8520, Japan Isoji Miyagi 1Geological Survey of Japan, AIST (National Institute of Advanced Industrial Science and Technology), Central 7, 1-1-1 Higashi, Tsukuba 305-8567, Japan Masato Joshima 1Geological Survey of Japan, AIST (National Institute of Advanced Industrial Science and Technology), Central 7, 1-1-1 Higashi, Tsukuba 305-8567, Japan Benjamin P. Weiss 3Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA Chris Shantz 3Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA Luis E. Fong 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Krista K. McBride 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Rene Harder 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Franz J. Baudenbacher 4Vanderbilt University, 2201 West End Avenue, Nashville, Tennessee 37235, USA Publisher: Geological Society of America Received: 26 Jul 2010 Revision Received: 30 Sep 2010 Accepted: 06 Oct 2010 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2011 Geological Society of America Geology (2011) 39 (3): 227–230. https://doi.org/10.1130/G31610.1 Article history Received: 26 Jul 2010 Revision Received: 30 Sep 2010 Accepted: 06 Oct 2010 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Hirokuni Oda, Akira Usui, Isoji Miyagi, Masato Joshima, Benjamin P. Weiss, Chris Shantz, Luis E. Fong, Krista K. McBride, Rene Harder, Franz J. Baudenbacher; Ultrafine-scale magnetostratigraphy of marine ferromanganese crust. Geology 2011;; 39 (3): 227–230. doi: https://doi.org/10.1130/G31610.1 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 Hydrogenetic ferromanganese crusts are iron-manganese oxide chemical precipitates on the seafloor that grow over periods of tens of millions of years. Their secular records of chemical, mineralogical, and textural variations are archives of deep-sea environmental changes. However, environmental reconstruction requires reliable high-resolution age dating. Earlier chronological methods using radiochemical and stable isotopes provided age models for ferromanganese crusts, but have limitations on the millimeter scale. For example, the reliability of 10Be/9Be chronometry, commonly considered the most reliable technique, depends on the assumption that the production and preservation of 10Be are constant, and requires accurate knowledge of the 10Be half-life. To overcome these limitations, we applied an alternative chronometric technique, magnetostratigraphy, to a 50-mm-thick hydrogenetic ferromanganese crust (D96-m4) from the northwest Pacific. Submillimeter-scale magnetic stripes originating from approximately oppositely magnetized regions oriented parallel to bedding were clearly recognized on thin sections of the crust using a high-resolution magnetometry technique called scanning SQUID (superconducting quantum interference device) microscopy. By correlating the boundaries of the magnetic stripes with known geomagnetic reversals, we determined an average growth rate of 5.1 ± 0.2 mm/m.y., which is within 16% of that deduced from the 10Be/9Be method (6.0 ± 0.2 mm/m.y.). This is the finest-scale magnetostratigraphic study of a geologic sample to date. Ultrafine-scale magnetostratigraphy using SQUID microscopy is a powerful new chronological tool for estimating ages and growth rates for hydrogenetic ferromanganese crusts. It provides chronological constraints with the accuracy promised by the astronomically calibrated magnetostratigraphic time scale (1–40 k.y.). You do not have access to this content, please speak to your institutional administrator if you feel you should have access.