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The Archaean: Geological and Geochemical Windows Into the Early Modern Approaches in Solid Earth Sciences Andrew Y. Glikson The Archaean: Geological and Geochemical Windows into the Early Earth The Archaean: Geological and Geochemical Windows into the Early Earth Modern Approaches in Solid Earth Sciences VOLUME 9 Series Editors Yildirim Dilek, Department of Geology and Environmental Earth Science, Miami University, Oxford, OH, U.S.A. Franco Pirajno, Geological Survey of Western Australia, and The University of Western Australia, Perth, Australia M.J.R. Wortel, Faculty of Geosciences, Utrecht University, The Netherlands For further volumes: http://www.springer.com/series/7377 Andrew Y. Glikson The Archaean: Geological and Geochemical Windows into the Early Earth Andrew Y. Glikson School of Archaeology and Anthropology and Planetary Science Institute Australian National University Canberra , Australian Capital Territory Australia Responsible Series Editor: F. Pirajno Additional material to this book can be downloaded from http://extras.springer.com ISSN 1876-1682 ISBN 1876-1690 (electronic) ISBN 978-3-319-07907-3 ISBN 978-3-319-07908-0 (eBook) DOI 10.1007/978-3-319-07908-0 Springer Cham Heidelberg New York Dordrecht London Library of Congress Control Number: 2014945202 © Springer International Publishing Switzerland 2014 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifi cally for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) The book is dedicated to the memory of Alec Trendall, pioneer of Precambrian research, as well as a tribute to the contributions to Archaean fi eld and isotopic geology and asteroid impact research by Arthur Hickman, Don Lowe, Allen Nutman, Bruce Simonson, Martin Van Kranendonk, Gary Byerly, Bob Pidgeon, Bill Compston, John Valley, Simon Wilde, Peter Haines and the late Ian Williams. Vestiges of a Beginning In dealing with rocks formed when the world was less than half of its present age, a strict adherence to the doctrine of uniformitarianism is considered unjustifi ed . (Macgregor 1951, p. 27) Determinations of the age of the Earth at 4.54 ± 0.05 billion years, based on radiometric U-Pb radiometric age of meteorites and consistent with the 4.567 Ga age of the solar system, as determined from Ca-Al inclusions in carbonaceous chon- drites, lunar samples and the oldest measured terrestrial zircons <4.404 Ga-old from the Jack Hills, Western Australia, leave large part of the earliest history of the planet unknown. Where the zircons signify relic felsic rocks as far back as ~4.4 Ga, due to selective retention of zircons and quartzite and destruction of more labile litholo- gies, i.e. mafi c and ultramafi c rocks, the composition of the bulk of the Earth crust at that stage remains unknown. Isotopic and geochemical signatures in rocks as old as ~3.8 Ga indicate an evolutionary trend from mafi c-ultramafi c crust to tonalite- trondhjemite- granodiorite (TTG)-dominated micro continental nuclei. To date, sig- natures of the 3.95–3.85 Ga Late heavy Bombardment (LHB), manifested by the lunar Mare, have not been discovered on Earth. ~4.0–3.8 Ga high-grade metamor- phic terrains, known from Slave province and Antarctica; ~3.8 Ga supracrustal volcanic-sedimentary belts represented by the Isua and Akilia terrains in southwest Greenland; and mafi c rocks from the northern Superior Province may conceal evi- dence for the LHB. Recent discoveries of near to 14 Archaean impact ejecta units up to 3.48 Ga-old intercalated with volcanic and sedimentary rocks in the Barberton and Pilbara greenstone belts, including clusters about 3.25–3.22 Ga and 2.63– 2.48 Ga in age, may represent terrestrial vestiges of an extended LHB. The interval of ~3.25–3.22 Ga ago emerges as a major break in Archaean crustal evolution when, as indicated by a major body of fi eld and isotopic age evidence, major asteroid bom- bardment resulted in faulting, large scale uplift, intrusion of granites and an abrupt shift from crustal conditions dominated by mafi c-ultramafi c crust associated with emplacement of tonalite-trondhjemite-granodiorite (TTG) plutons, to semi- continental nuclei represented by arenites, turbidites, conglomerate, banded iron formations and felsic volcanics. At this stage, pre-3.2 Ga dome-structured granite- greenstone systems were largely replaced by linear accretional granite-greenstone ix x Vestiges of a Beginning systems such as the Superior Province in Canada, Yilgarn Craton and the western Pilbara Craton, compared by some authors to circum-Pacifi c arc-trench settings. A fundamental geotectonic transformation is consistent with the increasing role of garnet fractionation as indicated by Al-depleted and plagioclase-enriched magmatic compositions, suggesting cooler high P/T (pressure/temperature) mantle and crustal magma sources, consistent with development of subduction. A concentration of large impacts during 2.63–2.48 Ga potentially accounts for peak magmatic events culminating the Archaean era. Strict comparisons between the Archaean systems and modern Arc-trench geotectonic setting will be shown to be unwarranted. These observations are considered in this monograph in the context of a review of major aspects of the Archaean record, in particular in the southern continents but with reference to northern cratons. The book provides an excursion through granite- greenstone terrains, and to a lesser extent high-grade metamorphic terrains, focus- ing on relic primary features including volcanic, sedimentary, petrological, geochemical and paleontological elements, with the aim of elucidating the nature of original environments and processes which dominated environments in which early life forms have emerged. By contrast to uniformitarian models, which take little or no account of repeated impacts of large asteroid clusters and their effects during ~3.47–2.48 Ga, the Archaean geological record will be shown to be consistent with the theory of asteroid impact-triggered geodynamic and magmatic activity originally advanced by D. H. Green in 1972 and 1981. Acknowledgements This book conveys my observations in Archaean terrains following my studies at the University of Western Australia during 1964–1968, my years in the Australian Geological Survey (BMR/AGSO/GA) during 1968–1996 and the Australian National University to the present. The list of people I like to thank is long; however I particularly like to thank those who have given me special collaboration, advice and support: John Vickers, for many years of collaboration in geological fi eld work in Western Australia; The late Alec Trendall and Tom Vallance, for their generous petrological advice during 1965–1967; Bill O’Beirne, Jack Hallberg, Gary Robinson and Kingsley Mills, for help with my Ph.D. thesis; Arthur Hickman, Franco Pirajno, the late Ian Williams, Peter Haines and Martin Van Kranendonk in connection with collaboration with the Geological Survey of Western Australia; the late Shen Su Sun, John Sheraton, Ian Lambert, Doone Wyborn, John Ferguson, Alan Whittaker, John Casey, the late Walter Dallwitz and Chris Pigram during my years in the BMR/ AGSO (now Geoscience Australia); David Green, Ian Jackson, Richard Arculus, Chris Klootwijk and Prame Chopra for support at the Research School of Earth Science, Australian National University. I thank my overseas colleagues for col- laboration, in particular Lutz Bischoff, Alec Baer, Don Lowe, Gary Byerly, Bruce Simonson, Scott Hassler, and Shigenori Maruyama. I am grateful to John Ferguson, Miryam Glikson, Victor Gostin, Arthur Hickman, Gerta Keller, Victor Masaitis, Franco Pirajno and Bruce Radke for reviews and comments on this book manuscript and to Brenda McAvoy for meticulous proof reading. I thank G. Byerly, Arthur Hickman, Michele McLeod, Reg Morrison, J-F Moyen, Allen Nutman, Bill Schopf, Bruce Simonson and John Valley, Geoscience Australia and the Geological Survey of Western Australia for permission
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