A test of (Ge/Si)opal as a paleorecorder of (Ge/Si)seawater

Abstract

Research Article| February 01, 1998 A test of (Ge/Si)opal as a paleorecorder of (Ge/Si)seawater Gilles Bareille; Gilles Bareille 1Département de Géologie et Océanographie, CNRS URA 197, Université de Bordeaux I, Avenue des Facultés, 33405 Talence Cedex, France Search for other works by this author on: GSW Google Scholar Monique Labracherie; Monique Labracherie 1Département de Géologie et Océanographie, CNRS URA 197, Université de Bordeaux I, Avenue des Facultés, 33405 Talence Cedex, France Search for other works by this author on: GSW Google Scholar Richard A. Mortlock; Richard A. Mortlock 2Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964 Search for other works by this author on: GSW Google Scholar Ernst Maier-Reimer; Ernst Maier-Reimer 3Max-Planck Institut für Meteorologie, Bundesstrasse 55, 20146 Hamburg, Germany Search for other works by this author on: GSW Google Scholar Philip N. Froelich Philip N. Froelich 4School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332-0340 Search for other works by this author on: GSW Google Scholar Geology (1998) 26 (2): 179–182. https://doi.org/10.1130/0091-7613(1998)026<0179:ATOGSO>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Gilles Bareille, Monique Labracherie, Richard A. Mortlock, Ernst Maier-Reimer, Philip N. Froelich; A test of (Ge/Si)opal as a paleorecorder of (Ge/Si)seawater. Geology 1998;; 26 (2): 179–182. doi: https://doi.org/10.1130/0091-7613(1998)026<0179:ATOGSO>2.3.CO;2 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 Late Pleistocene variations of germanium to silicon ratios in marine diatom shells from sediment cores, (Ge/Si)opal, are coherent with the global isotope record of glacial to interglacial climate change. These variations are thought to reflect changes in (Ge/Si)seawater driven by climate-modulated alterations in oceanic Ge/Si sources and sinks. However, an important criterion for interpreting (Ge/Si)opal as a monitor of whole ocean (Ge/Si)seawater is that the opal burial ratio be insensitive both to local diatom production and surface ocean silica concentrations (so-called biological fractionation effects) and to differential dissolution artifacts (so-called diagenesis offsets). Here we test these assumptions by comparing model ocean sediment (Ge/Si)opal distributions with data from Holocene and glacial sediments across the high-latitude Indian-Antarctic Ocean siliceous ooze belt. In contrast to the model, the data show no gradients in either Holocene or glacial (Ge/Si)opal values across productivity zones displaying dramatic changes in biosiliceous production, opal burial, and dissolution. This evidence supports the contention that fractionation effects are small and that observed down-core variations in (Ge/Si)opal faithfully record secular changes in (Ge/Si)seawater. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.