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One Hundred Years of Geochronology

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One Hundred Years of Geochronology Elements is published jointly by the Mineralogical Volume 9, Number 1 • February 2013 ABOUT THE COVER: Society of America, the Mineralogical Society Zircon is among the of Great Britain and Ireland, the Mineralogical premier geochronometers Association of Canada, the Geochemical Society, One Hundred Years described in this issue. The Clay Minerals Society, the European Illustrated is a Nomarski Association of Geochemistry, the Inter national of Geochronology contrast image of an Association of GeoChemistry, the Société acid-etched zircon Française de Minéralogie et de Cristallographie, Guest Editors: Daniel J. Condon and Mark D. Schmitz from a 4.03 Ga tonalite the Association of Applied Geochemists, of the Acasta gneiss the Deutsche Mineralogische Gesellschaft, the Società Italiana di Mineralogia e Petrologia, One Hundred Years of Isotope complex, Canada, with the International Association of Geoanalysts, 15 Geochronology, and Counting ion probe analysis craters the Polskie Towarzystwo Mineralogiczne Daniel J. Condon and Mark D. Schmitz labeled in millions of (Mineralogical Society of Poland), the Sociedad years (IMAGE COURTESY Española de Mineralogía, the Swiss Society of OF SAMUEL A. BOWRING Mineralogy and Petrology, the Meteoritical AND IAN S. WILLiaMS). Society, and the Japan Association of Mineralogical Precision and Accuracy The background image Sciences. It is provided as a benefit to members shows zircon crystals of these societies. 19 in Geochronology on matrix from the Kola Elements is published six times a year. Individuals Blair Schoene, Daniel J. Condon, Leah Morgan, Peninsula (© MORGENSTJERNE Faneromeni La2004(1,1) FC40 Insolation Precession | DREAMSTIME.COM). min max min max are encouraged to join any one of the partici- FC36 6.6 3 ka and Noah McLean FC28 3 ka pating societies to receive Elements. Institutional A1 FC32 6.8 subscribers to any of the following journals— FC28 Ma Faneromeni Crete High-Precision Geochronology 7.0 25 American Mineralogist, Clay Minerals, Clays and FC24 100km approx. location 35.2˚N, 26.2˚E Clay Minerals, Mineralogical Magazine, and The 7.2 Mark D. Schmitz and Klaudia F. Kuiper Tu rbidite 2 Sapropel Canadian Miner alogist—also receive one copy 0 m Marl of Elements as part of their 2013 subscription. a 7 Institu tional subscriptions are available for High-Spatial-Resolution Geochronology 16 US$160 (US$175 non-US addresses) a year in 31fO Alexander A. Nemchin, Matthew S. A. Horstwood, 180 2013. Contact the managing editor (tremblpi@ /H 6 UO and Martin J. Whitehouse ete.inrs.ca) for information. 81 23 Copyright 2013 by the Mineralogical Society 10 µm of America 0 Dating the Oldest Rocks and Minerals in the Solar System b 392.111 All rights reserved. Reproduction in any form, Yuri Amelin and Trevor R. Ireland including translation to other languages, or by 16 any means—graphic, electronic, or mechanical, fO 180 including photocopying or information storage /H Pb and retrieval systems—without written permission 206 Time Constraints and Tie-Points in the Quaternary Period 45 David A. Richards and Morten B. Andersen from the copyright holder is strictly prohibited. 10 µm 0 Publications mail agreement no. 40037944 0.5 Printed in USA 0.4 b Revolution and Evolution: ISSN 1811-5209 (print) 206 0.3 /P ISSN 1811-5217 (online) 53 Pb 207 100 Years of U–Pb Geochronology www.elementsmagazine.org 0.2 James M. Mattinson 10 µm www.elements. 0.1 geoscienceworld.org DEPARTMENTS Editorial – The Age of the Earth .......................3 From the Editors – Introducing Patricia Dove .............4 People in the News – Berner, Schopf, AGU Fellows .........6 Elements Toolkit – Field-Portable XRF ..................7 Meet the Authors ...............................12 Society News Association of Applied Geochemists ...................58 The Clay Minerals Society ...........................59 International Association of GeoChemistry ..............60 International Association of Geoanalysts ................61 Japan Association of Mineralogical Sciences .............62 Meteoritical Society . .63 Mineralogical Society of Great Britain and Ireland .........64 Mineralogical Society of America ......................66 Geochemical Society ...............................68 Société Française de Minéralogie et de Cristallographie ....69 Mineralogical Association of Canada . 70 European Association of Geochemistry .................72 Società Italiana di Mineralogia e Petrologia ..............74 Association Internationale pour l’Étude des Argiles ........75 Book Review – Quantitative Mineralogy and Microanalysis in Sediments and Sedimentary Rocks ..................76 Calendar ......................................77 Parting Shots – A Record Brimful of Promise ............79 Advertisers in This Issue .........................80 1.
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