Th E Age of the Earth

Total Page:16

File Type:pdf, Size:1020Kb

Th E Age of the Earth EDITORIAL TH E AGE OF THE EARTH PRINCIPAL EDITORS JAMES I. DREVER, University of Wyoming, USA (drever@uwyo.edu) The “Age of the Earth” is of 200 students, “Have you had a discussion with GEORGES CALAS, IMPMC, France one of the most common someone who thinks the Earth is much younger (Georges.Calas@impmc.jussieu.fr) JOHN W. VALLEY, University of Wisconsin, USA titles in the geological than 4500 million years?”, and about 50% say (valley@geology.wisc.edu) literature, and with good “yes.” I then have 50 minutes to talk about how PATRICIA M. DOVE, Virginia Tech (dove@vt.edu) reason. The scientific rocks are dated and to compare 4500 Ma with ADVISORY BOARD 2012 and philosophical impli- earlier estimates. I explain that geochronology is JOHN BRODHOLT, University College London, UK cations are immense. based on observable data and that the hypotheses NORBERT CLAUER, CNRS/UdS, Université de Strasbourg, France This issue of Elements is are testable, and I encourage students to at least WILL P. GATES, SmecTech Research Consulting, devoted to measuring look through the windows of clean-labs to see Australia th GEORGE E. HARLOW, American Museum geologic time on the 100 people running mass spectrometers. The serious of Natural History, USA John Valley anniversary of a book students may read this issue of Elements and get JANUSZ JANECZEK, University of Silesia, Poland HANS KEPPLER, Bayerisches Geoinstitut, with this title (Holmes an appreciation for the depth and complexity of Germany 1913). The book is a good read—a clear historical determining age, but no fi rst-year student, and DAVID R. LENTZ, University of New Brunswick, Canada account, with groundbreaking science that still certainly no younger student, is in the position ANHUAI LU, Peking University, China stirs controversy today. It’s available free online. to make these observations themselves. The data ROBERT W. LUTH, University of Alberta, Canada DAVID W. MOGK, Montana State University, USA are observable to specialists running mass spec- TAKASHI MURAKAMI, University of Tokyo, Japan Arthur Holmes was the fi rst to use radioactivity to trometers, but not to most others. The scientifi c ROBERTA OBERTI, CNR Istituto di Geoscienze e date a range of rocks, and before Dempster discov- Georisorse, Pavia, Italy 235 method is less interesting, and far less compel- TERRY PLANK, Lamont-Doherty Earth ered U in 1935, Holmes estimated Earth’s age at ling, when someone can’t make the observations Observatory, USA 1600–3000 million years (Ma) (Holmes 1927). This XAVIER QUEROL, Spanish Research Council, Spain themselves. MAURO ROSI, University of Pisa, Italy estimate was not improved on BARBARA SHERWOOD LOLLAR, University of until 1953, when Clair Patterson, Thus we also need to explain Toronto, Canada TORSTEN VENNEMANN, Université de using a more advanced mass why the Earth cannot be 6000 Lausanne, Switzerland “It is perhaps a little OLIVIER VIDAL, Université J. Fourier, France spectrometer, published the age years old using evidence that MEENAKSHI WADHWA, Arizona State of 4510–4560 Ma, soon refi ned indelicate to ask of our is more easily observed and University, USA to 4550 ± 70 Ma (Patterson 1953, understood by a layperson, BERNARD WOOD, University of Oxford, UK Mother Earth her age.” JON WOODHEAD, University of Melbourne, 1956), in perfect agreement with such as tree rings, varves, Australia modern estimates (this issue). In —Arthur Holmes (1913) layers in glacial ice, and rates EXECUTIVE COMMITTEE detail, geochronometers using of weathering, erosion, sedi- CARLOS AYORA IBÁÑEZ, Sociedad Española di Mineralogía extinct, short-lived isotopes have ment deposition, and cooling THOMAS D. BULLEN, International Association of GeoChemistry now shown that Earth accreted of plutons, just to name a few. BERNARDO CESARE, Società Italiana di over an interval of time, which is within the If the Pyramids are still standing after 5000 years, Mineralogia e Petrologia KATERINA M. DONTSOVA, The Clay Minerals uncertainty of Patterson’s age (e.g. Halliday 2006). how can the Grand Canyon form in 6000? Many Society There are many excellent accounts of this history arguments made by Hutton and Lyell two cen- BARBARA L. DUTROW, Mineralogical Society of America, Chair (Burchfi eld 1975; Dalrymple 1991; Lewis 2000; turies ago apply today. This brings me back to DANIEL J. FROST, European Association Lewis and Knell 2001). Holmes’s book, which reviews earlier estimates of Geochemistry BERNARD GROBÉTY, Swiss Society of and was written at the end of the remarkable Mineralogy and Petrology While most readers of Elements understand that MARK E. HODSON, Mineralogical Society period before the First World War. of Great Britain and Ireland geochronology is based on observable data, refut- GUY LIBOUREL, Société Française de Minéralogie able hypotheses, and repeatable tests, the age of At the end of the 19th century, Lord Kelvin et de Cristallographie HARRY Y. McSWEEN, Meteoritical Society the Earth, like evolution, continues to be chal- famously concluded that Earth formed 20–40 MAREK MICHALIK, Mineralogical Society lenged. Creationist beliefs, which morphed into million years ago based on a simple thermal of Poland TAKASHI MURAKAMI, Japan Association Intelligent Design, are common. Questions of model (Kelvin 1895, 1899). This was disputed by of Mineralogical Sciences faith address issues that are outside the realm of geologists, who maintained that more time was IAIN M. SAMSON, Mineralogical Association of Canada science, which deals with what we can observe needed to explain the evolution of Earth or life. EDWIN A. SCHAUBLE, Geochemical Society and test. Nevertheless, some politicians pub- Kelvin’s (1899) fi nal estimate of 24 Ma old. elicited CLIFFORD R. STANLEY, Association of Applied Geochemists licly proclaim that no one knows the age of the a strong response from T. C. Chamberlin (1899). FRIEDHELM VON BLANCKENBURG, Deutsche Mineralogische Gesellschaft Earth, with the implication that modern science The discussion at that time was far-reaching, MICHAEL WIEDENBECK, International is wrong, and demands are made to include “sci- and included Laplace’s solar nebula hypothesis Association of Geoanalysts entifi c creationism” in science courses. as opposed to the newer idea of planetesimals, MANAGING EDITOR hot versus cold accretion of Earth, advective heat PIERRETTE TREMBLAY, tremblpi@ete.inrs.ca The age of the Earth is not controversial among transfer in the mantle, the source of heat in the EDITORIAL OFFICE scientists. Clear rebuttals to young-Earth advo- Sun, and the fi rst habitats for life on Earth. Kelvin cates include those by Dalrymple (1991) and was confi dent in his position because the age of Wiens (2002). The academies of science in 67 the Sun was estimated to be less than 20 Ma, nations have formally concluded that “within sci- based on the assumption that its energy derived ence courses taught in certain public systems of from chemical reactions or gravitational energy education, scientifi c evidence, data, and testable 490, rue de la Couronne during compression. At a time when radioactivity Québec (Québec) G1K 9A9, Canada theories about the origins and evolution of life on was unknown, it was a stretch to conceive of a hot Tel.: 418-654-2606 Fax: 418-653-0777 Earth are being concealed, denied, or confused Layout: POULIOT GUAY GRAPHISTES Sun more than 20 Ma old. Chamberlin questioned Copy editor: THOMAS CLARK with theories not testable by science” and that no nearly all of Kelvin’s assumptions, prophetically Proofreaders: THOMAS CLARK scientifi c evidence contradicts the age of 4500 Ma and DOLORES DURANT enquiring: Printer: ALLEN PRESS for Earth or the theory of evolution (IAP 2006). The publishers assume no responsibility for If we all agree, why do we need to talk about it? “Is the present knowledge relative to the behavior any statement of fact or opinion expressed of matter under such extraordinary conditions as in the published material. The appearance of The question is: how best to explain the age of the advertising in this magazine does not constitute obtained in the interior of the sun suffi ciently endorsement or approval of the quality or value Earth to nonscientists? We confront this in many of the products or of claims made for them. venues, including education at all levels. Each www.elementsmagazine.org year, at the University of Wisconsin, I ask classes Cont’d on page 4 ELEMENTS 3 FEBRUARY 2013 FROM THE EDITORS THIS ISSUE INTRODUCING PATRICIA DOVE, This issue takes us on a voyage in time, starting with the discovery of PRINCIPAL EDITOR 2013–2015 radioactivity and carrying us forward to today. We meet the giants the With the start of 2013, Patricia M. (Trish) Dove fi eld of geochronology is indebted to. We see the challenges that have joins the Elements team as a principal editor. Trish been met and those that lie ahead. We are reminded that for a mineral is the C. P. Miles Professor of Science in the date to have meaning, the context of the mineral analyzed and the Department of Geosciences at Virginia Tech. She rock of which it is a constituent must be thoroughly documented. And earned her bachelor’s and master’s degrees at this is an overarching theme of all papers in this issue. Virginia Tech, then her PhD at Princeton, and she completed a postdoctoral fellowship at It took me a while to understand the “crisis” mentioned in the Schmitz Stanford. Trish is one of the outstanding geo- and Kuiper article. After all, 251.2 ±3.4 Ma and 249.98 ±0.2 Ma seemed chemists of her generation. She has made wide- like dates in pretty good agreement. But as geochronology matures and ranging contributions in the biogeochemistry of instruments allow higher precision, scientists set out to answer ever Earth processes, which includes mineral surface more complex questions. processes at the molecular scale, the kinetics of geochemical processes, While checking facts on the Web, I learned that Rutherford did most mineral–microbe interactions, and biomineralization.
Recommended publications
  • PDF— Granite-Greenstone Belts Separated by Porcupine-Destor
    C G E S NT N A ER S e B EC w o TIO ok N Vol. 8, No. 10 October 1998 es st t or INSIDE Rel e • 1999 Section Meetings ea GSA TODAY Rocky Mountain, p. 25 ses North-Central, p. 27 A Publication of the Geological Society of America • Honorary Fellows, p. 8 Lithoprobe Leads to New Perspectives on 70˚ -140˚ 70˚ Continental Evolution -40˚ Ron M. Clowes, Lithoprobe, University -120˚ of British Columbia, 6339 Stores Road, -60˚ -100˚ -80˚ Vancouver, BC V6T 1Z4, Canada, 60˚ Wopmay 60˚ clowes@lithoprobe.ubc.ca Slave SNORCLE Fred A. Cook, Department of Geology & Thelon Rae Geophysics, University of Calgary, Calgary, Nain Province AB T2N 1N4, Canada 50˚ ECSOOT John N. Ludden, Centre de Recherches Hearne Pétrographiques et Géochimiques, Taltson Vandoeuvre-les-Nancy, Cedex, France AB Trans-Hudson Orogen SC THOT LE WS Superior Province ABSTRACT Cordillera AG Lithoprobe, Canada’s national earth KSZ o MRS 40 40 science research project, was established o Grenville Province in 1984 to develop a comprehensive Wyoming Penokean GL -60˚ understanding of the evolution of the -120˚ Yavapai Province Orogen Appalachians northern North American continent. With rocks representing 4 b.y. of Earth -100˚ -80˚ history, the Canadian landmass and off- Phanerozoic Proterozoic Archean shore margins provide an exceptional 200 Ma - present 1100 Ma 3200 - 2650 Ma opportunity to gain new perspectives on continental evolution. Lithoprobe’s 470 - 275 Ma 1300 - 1000 Ma 3400 - 2600 Ma 10 study areas span the country and 1800 - 1600 Ma 3800 - 2800 Ma geological time. A pan-Lithoprobe syn- 1900 - 1800 Ma 4000 - 2500 Ma thesis will bring the project to a formal conclusion in 2003.
    [Show full text]
  • When the Earth Moves Seafloor Spreading and Plate Tectonics
    This article was published in 1999 and has not been updated or revised. BEYONDBEYOND DISCOVERYDISCOVERYTM THE PATH FROM RESEARCH TO HUMAN BENEFIT WHEN THE EARTH MOVES SEAFLOOR SPREADING AND PLATE TECTONICS arly on the morning of Wednesday, April 18, the fault had moved, spanning nearly 300 miles, from 1906, people in a 700-mile stretch of the West San Juan Bautista in San Benito County to the south E Coast of the United States—from Coos Bay, of San Francisco to the Upper Mattole River in Oregon, to Los Angeles, California—were wakened by Humboldt County to the north, as well as westward the ground shaking. But in San Francisco the ground some distance out to sea. The scale of this movement did more than shake. A police officer on patrol in the was unheard of. The explanation would take some six city’s produce district heard a low rumble and saw the decades to emerge, coming only with the advent of the street undulate in front of him, “as if the waves of the theory of plate tectonics. ocean were coming toward me, billowing as they came.” One of the great achievements of modern science, Although the Richter Scale of magnitude was not plate tectonics describes the surface of Earth as being devised until 1935, scientists have since estimated that divided into huge plates whose slow movements carry the the 1906 San Francisco earthquake would have had a continents on a slow drift around the globe. Where the 7.8 Richter reading. Later that morning the disaster plates come in contact with one another, they may cause of crushed and crumbled buildings was compounded by catastrophic events, such as volcanic eruptions and earth- fires that broke out all over the shattered city.
    [Show full text]
  • Parting Shots
    PARTING SHOTS A RECORD BRIMFUL OF PROMISE Arthur Holmes is mentioned in several articles tifi c work at what we now call Imperial College, in this issue, by John Valley in his editorial, in London, and Cherry Lewis gives a detailed by Condon and Schmitz in their introductory account of his troubled work with the minerals article, and by Mattinson in his review of the industry in Mozambique and the petroleum U–Pb method. Google ‘Arthur Holmes’ and industry in Burma. His main academic career you will fi nd a lot of articles about his scien- began in 1924 when he was given the job of tifi c work, and there is a very readable biog- starting a department of geology at Durham raphy by Cherry Lewis which strikes a nice University, where 40 years later I obtained both balance between his scientifi c and personal my degrees. The student geological society in life. There is no question that he was a giant Durham is still called ‘The Arthur Holmes of 20th-century Earth science. The U–Pb age of Geological Society’. In 1943 he took up the 370 Ma that he obtained for accessory minerals Chair of Geology at Edinburgh where I’m Diagrammatic section across the “FIGURE 744: separated from a nepheline syenite from the writing now. I pass his picture every time I Andesite Line and a typical island arc Christiania region of Norway (Holmes 1911) is go up the main stairs in the Grant Institute (e.g. Japan or Kamchatka) to illustrate a speculative arrangement of convection currents which might a milestone not just for geology but for other (my fi rst picture).
    [Show full text]
  • I5 Wegener's Geological Evidence for Pangea < Holmes >
    WEGENER AND CONTINENTAL DRIFT 493 i5 Wegener’s geological evidence for Pangea < Holmes > The term Pangea (or Pangaea) comes from the Greek ‘pan’=all, entire + ‘gaea’=land, Earth. The name is frequently stated to have been coined by Alfred Wegener (1914) in Die Entstehung der Kontinente und Ozeane (The Origin of the Continents and Oceans), but it has not been found in the 1st edition of that book.—Georoots.1 The first use of the word [Pangea] comes in a 1924 translation of Wagener’s book, by the man named Skerl.—Winchester.2 And in fact the word is used in Wegener’s book but not as a proper noun (and so it cannot be found in the book’s index) in the sentence ‘Schon die Pangäa [the pangæa] der Karbonzeit hatte so einen Vorderrand (Amerika) ...’ once in the 1920 edition, p. 120, and again so once in the 1922 edition, p. 131. Pangea is first used as a proper noun by J. W. Evans in his introduction to the 1924 book.—HR. The geological evidence that Wegener marshaled to support his reconstruction of a primordial continent (Pangea) was vast in scope. A deduction would be that fossils of closely related land animals and plants should be now separated by wide oceans if Pangea had existed. Wegener, at first, was not able to give examples and this could be construed to negate the once existence of Pangea. But later, Wegener did find some examples and Arthur Holmes favorably observed: “Negative evidence may be destroyed at any moment by fresh discoveries, whereas genuine positive evidence can never be explained away.” 3 However, landbridges could be evoked to explain the fossil data.
    [Show full text]
  • The Historical Background
    01 orestes part 1 10/24/01 3:40 PM Page 1 Part I The Historical Background The idea that continents move was first seriously considered in the early 20th century, but it took scientists 40 years to decide that it was true. Part I describes the historical background to this question: how scientists first pondered the question of crustal mobility, why they rejected the idea the first time around, and how they ultimately came back to it with new evidence, new ideas, and a global model of how it works. 01 orestes part 1 10/24/01 3:40 PM Page 2 01 orestes part 1 10/24/01 3:40 PM Page 3 Chapter 1 From Continental Drift to Plate Tectonics Naomi Oreskes Since the 16th century, cartographers have noticed the jigsaw-puzzle fit of the continental edges.1 Since the 19th century, geol- ogists have known that some fossil plants and animals are extraordinar- ily similar across the globe, and some sequences of rock formations in distant continents are also strikingly alike. At the turn of the 20th cen- tury, Austrian geologist Eduard Suess proposed the theory of Gond- wanaland to account for these similarities: that a giant supercontinent had once covered much or all of Earth’s surface before breaking apart to form continents and ocean basins. A few years later, German meteo- rologist Alfred Wegener suggested an alternative explanation: conti- nental drift. The paleontological patterns and jigsaw-puzzle fit could be explained if the continents had migrated across the earth’s surface, sometimes joining together, sometimes breaking apart.
    [Show full text]
  • GSA TODAY North-Central, P
    Vol. 9, No. 10 October 1999 INSIDE • 1999 Honorary Fellows, p. 16 • Awards Nominations, p. 18, 20 • 2000 Section Meetings GSA TODAY North-Central, p. 27 A Publication of the Geological Society of America Rocky Mountain, p. 28 Cordilleran, p. 30 Refining Rodinia: Geologic Evidence for the Australia–Western U.S. connection in the Proterozoic Karl E. Karlstrom, kek1@unm.edu, Stephen S. Harlan*, Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 Michael L. Williams, Department of Geosciences, University of Massachusetts, Amherst, MA, 01003-5820, mlw@geo.umass.edu James McLelland, Department of Geology, Colgate University, Hamilton, NY 13346, jmclelland@mail.colgate.edu John W. Geissman, Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131, jgeiss@unm.edu Karl-Inge Åhäll, Earth Sciences Centre, Göteborg University, Box 460, SE-405 30 Göteborg, Sweden, ahall@geo.gu.se ABSTRACT BALTICA Prior to the Grenvillian continent- continent collision at about 1.0 Ga, the southern margin of Laurentia was a long-lived convergent margin that SWEAT TRANSSCANDINAVIAN extended from Greenland to southern W. GOTHIAM California. The truncation of these 1.8–1.0 Ga orogenic belts in southwest- ern and northeastern Laurentia suggests KETILIDEAN that they once extended farther. We propose that Australia contains the con- tinuation of these belts to the southwest LABRADORIAN and that Baltica was the continuation to the northeast. The combined orogenic LAURENTIA system was comparable in
    [Show full text]
  • Arthur Holmes with Maggie, Born
    RROCKOCK STARS STARS great synthesis, The Face of the Earth, had recently been trans- lated into English. Holmes later remarked how the inspirational Mr. McIntosh and these two works were largely responsible for the direction his life took, for it was at school that his interests in physics and geology were Arthur Holmes with Maggie, born. At 17, he won a scholar- his first wife, and Geoffrey, his ship to study physics at the Royal second son, in Durham, ca. 1930. College of Science (later Imperial College) in London where, in his second year, he took a course in geology. Against the advice of his physics tutors, he decided to become a geologist. Radioactivity had been discovered in 1896 and was causing much excitement. By 1904, Ernest Rutherford had determined the first radiometric date, utilizing the discovery that helium was gen- erated in the decay process. Unfortunately, owing to the problem of helium leakage, these early dates were only minimum values, so Holmes decided to combine his interest in physics and geol- ogy in the search for an alternative technique. Building on Bertram Boltwood’s work, which indicated that lead might be the Arthur Holmes as a young man in his early 20s. This photo was final decay product of uranium, Holmes performed the very first probably taken in 1912 when Holmes joined the Geological Society uranium-lead analysis specifically determined for age-dating pur- of London. poses. It yielded 370 Ma for a Devonian rock. Aged only 21, he had embarked on his lifetime’s quest “to graduate the geological column with an ever-increasingly accurate time scale.” In April Arthur Holmes: 1911, the paper was read to members of the Royal Society while An Ingenious Geoscientist Holmes was in Mozambique.
    [Show full text]
  • Burlington House Fire Safety Information
    Arthur Holmes Meeting 2016 Contents Page 2 Sponsors Acknowledgement Page 3 Oral Presentation Programme Page 8 Oral Presentation Abstracts Page 124 Posters Page 127 Poster Presentation Abstracts Page 153 Burlington House Fire Safety Information Page 154 Ground Floor Plan of The Geological Society Burlington House Page 155 2016 Geological Society Conferences 23-25 May 2016 Page 1 #ahwilson16 Arthur Holmes Meeting 2016 We gratefully acknowledge the support of the sponsors for making this meeting possible. 23-25 May 2016 Page 2 #ahwilson16 Arthur Holmes Meeting 2016 Oral Presentation Programme Monday 23 May 2016 08.30 Registration & tea & coffee (Main foyer and Lower Library) 09.00 Introduction The Wilson & Supercontinent Cycles 09.10 KEYNOTE: The Wilson Cycle Of the Opening and the Closing of the Ocean Basins Kevin Burke (University of Houston, Texas, USA) 09.40 Geo-Constraints on and confirmation of the operation of the Wilson Cycle since the Neoarchaean Brian Windley (University of Leicester, UK) 10.00 Mesoproterozoic terrane collision in the Namaqua belt of south-western Africa - Time for revision of deeply entrenched views? Steffen Büttner (Rhodes University, South Africa) 10.20 The Classic Wilson Cycle Revisited Ian W.D Dalziel (The University of Texas at Austin, Texas, USA) 10.40 Tea, coffee, refreshments and posters (Lower Library) Record of the Wilson Cycle 11.00 KEYNOTE: Dyke Swarms of the Canadian Shield: Initial Stages of Precambrian Wilson Cycles? Henry C. Halls (University of Toronto Mississauga, Canada) 11.30 A revised 300 Ma geodynamic history for the Iapetian Wilson cycle, based on Hf isotope arrays. Bill Collins (The University of Newcastle, Australia) 11.50 Sea level reconstruction from Strontium isotopes; a record of the Wilson Cycle back to the Neoproterozoic Douwe van der Meer 12.10 Natural Resource Evaluation within a Global Tectonic Framework: The Past is the Key to the Future G.R.
    [Show full text]
  • Plate Tectonics
    Plate Tectonics Plate tectonics is responsible for: .Volcanoes .Earthquakes .Mountain belts (e.g., Rockies) .Normal faults .Reverse/thrust faults .Transform (strike-slip) faults .Age of the ocean crust .Sediment in Deltas .Etc., etc., etc., etc…. Time Alfred Wegener Breakup of Pangaea. 1 Evidence of continental drift — 1: Glacial deposits. Striations Glaciated areas Reconstructed ice sheet on Pangaea. Distribution of glacial deposits today. Evidence of continental drift — 1: Climate belts Rock types indicative of specific climates align in belts, at appropriate latitudes, on Pangaea. coal salt ice sheet subtropical sand dune reef tropical 2 Evidence of continental drift — 3: Distribution fossils Mesosaurus Lystrosaurus Cynognathus Glossopteris Fossils of the same land organisms occur on all continents. Evidence of continental drift — 3: Similarity of rocks across the Atlantic Archean crust Proterozoic mountain belts Mountain belt Archean crustal blocks. Late Paleozoic mountain belts. 3 Today, geologists can measure plate velocities in real time. This information is critical for earthquake hazard prediction. 4 plate velocities and plate motion The Key Features of Plate Tectonics (1) The Earth’s crust is continually created and destroyed (recycled). (2) Ocean crust, formed at divergent margins, is mafic and dense. (3) As ocean crust ages and cools, it sinks beneath continents at convergent subduction zones. (4) Because Earth is a spherical body, there are also transform (strike-slip) boundaries that accommodate motion parallel to the current overall motion of the plates. 5 Divergent Convergent Transform The three types are defined by the relative motion of plates. 6 Basic Plate Boundaries Geologists define three types of plate boundary, based simply on the relative motions of the plates on either side of the boundary.
    [Show full text]
  • Arthur Holmes' Paper of 1929 on Convection Currents Within the Earth
    41 Classic papers 41 by David Oldroyd Arthur Holmes’ paper of 1929 on convection currents within the Earth as a cause of continental drift School of History and Philosophy, The University of New South Wales, NSW 2052, Australia. E-mail: d.oldroyd@unsw.edu.au Arthur Holmes (1890–1965) masses plough through the Earth’s crust like ships at sea? Wegener’s suggestions, such as the idea of ‘pole-flight’ due to the Holmes is widely regarded as one of the finest geologists of the Earth’s rotation, were obviously insufficient to account for the ‘drift’ twentieth century and probably the greatest British geologist of his of continents. On the other hand, seismic evidence (e.g. Oldham, day. He was professor first at the Durham University and then at 1906) suggested that some—in fact much—of the Earth’s interior Edinburgh, where he is still revered. He did substantial work in Africa was fluid. and Burma and made contributions in petrology, geomorphology, At the time of Holmes’s Glasgow paper the tide of opinion was geophysics, structural geology and geochronology. His knowledge definitely running against Wegener’s theory, as shown most clearly of the geological literature and world geology was comprehensive. in the proceedings of a conference organised by the American Holmes was also the author of an extremely successful geology Association of Petroleum Geologists in New York in 1926 (van textbook (Holmes, 1944 and 1964). But perhaps his most important Waterschoot van der Gracht, 1928), where the majority of participants work involved the study of radioactive materials as a pioneering means spoke against the drift hypothesis.
    [Show full text]
  • The Dating Game One Man’S Search for the Age of the Earth Cherry Lewis
    The Dating Game One Man’s Search for the Age of the Earth cherry lewis Ff It is perhaps a little indelicate to ask of our Mother Earth her age, but Science acknowledges no shame. published by the press syndicate of the university of cambridge The Pitt Building, Trumpington Street, Cambridge, United Kingdom cambridge university press The Edinburgh Building, Cambridge CB2 2RU, UK 40 West 20th Street, New York, NY 10011–4211, USA 10 Stamford Road, Oakleigh, VIC 3166, Australia Ruiz de Alarcón 13, 28014 Madrid, Spain Dock House, The Waterfront, Cape Town 8001, South Africa http://www.cambridge.org Cherry Lewis 2000 This book is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2000 Printed in the United Kingdom at the University Press, Cambridge Typeface Quadraat System QuarkXPress®[w21] A catalogue record for this book is available from the British Library Library of Congress Cataloguing in Publication data Lewis, Cherry, 1947– The dating game : searching for the age of the Earth / by Cherry Lewis. p. cm. “It is perhaps a little indelicate to ask of our Mother Earth her age, but science acknowledges no shame.” Includes bibliographical references. ISBN 0 521 79051 4 1. Earth – Age. 2. Geological time. 3. Holmes, Arthur, 1890–1965. I. Title. QE508 .L48 2000 551.7′01–dc21 00–023615 ISBN 0 521 79051 4 hardback Contents Ff List of Illustrations viii Prelude to the
    [Show full text]
  • GSA TODAY • 1998 Section Meetings a Publication of the Geological Society of America Southeastern, P
    Vol. 7, No. 10 October 1997 INSIDE • New Honorary Fellows, p. 15 • Call for Award Nominations, p. 16, 22, 24, 26 GSA TODAY • 1998 Section Meetings A Publication of the Geological Society of America Southeastern, p. 27 Cordilleran, p. 29 Postglacial Ponds and Alluvial Fans: Recorders of Holocene Landscape History Paul Bierman,* Andrea Lini, Paul Zehfuss, Amy Church, Department of Geology, University of Vermont, Burlington, VT 05405 P. Thompson Davis, Department of Natural Sciences, Bentley College, Waltham, MA 02154 John Southon, Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94550 Lyn Baldwin, Field Naturalist Program, University of Vermont, Burlington, VT 05405 ABSTRACT northern Vermont as an example, alluvial fan sediments reveal that we demonstrate that the sedimentary the highest rates of hillslope erosion Little is known about rates and record preserved in humid-region occurred as a consequence of European patterns of Holocene hillslope erosion ponds and alluvial fans can be dated, settlement. The geologic record of colo- in areas once covered by Pleistocene ice deciphered isotopically and stratigraph- nial deforestation is clear, revealing sheets and now heavily populated. Yet, ically, and used to understand the his- significant human impact and suggest- understanding past landscape behavior tory of hillslope erosion. Our data sug- ing that past landscape response is a is prerequisite to predicting and mitigat- gest that erosion rates were higher in meaningful basis for guiding future ing future impacts of human-induced the early and late Holocene than in the land management practices. disturbance and climate change. Using mid-Holocene, perhaps the result of changing climate and the frequency INTRODUCTION *E-mail address: pbierman@zoo.uvm.edu.
    [Show full text]