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Biostratigraphy: Microfossils and Geological Time Brian Mcgowran Frontmatter More Information Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information Biostratigraphy Microfossils and Geological Time Using fossils to tell geological time, biostratigraphy balances biology with geology. In modern geochronology – meaning timescale-building and making correlations between oceans, continents and hemispheres – the microfossil record of speciations and extinctions is integrated with numerical dates from radioactive decay, geomagnetic reversals through time, and the cyclical wobbles of the Earth-Sun-Moon system. This important modern synthesis follows the development of biostratigraphy from classical origins into petroleum exploration and deep-ocean drilling. It explores the three-way relationship between species of micro-organism, their environments and their evolution through time as expressed in skeletons preserved as fossils. This book is essential reading for advanced students and researchers working in basin analysis, sequence stratigraphy, palaeoceanography, palaeobiology and related fields. B RIAN M C G OWRAN worked as a governmental and consultant geologist- palaeontologist in Australia, New Guinea and the southwest Pacific for several years. For three decades he was an academic, teaching and supervising in a wide range of the Earth sciences, and he has held visiting positions at the Universities of Vienna and Princeton and at the Geological Survey of Austria. His previous publications include technical books on geological excursions through the famous and touristic Cenozic outcrops of southern Australia, as well as over 200 journal articles. Oceanic drilling in the Indian Ocean in the early days of the Deep Sea Drilling Project anchored his long-time interest in the history of the Cenozoic Era and especially on the interplay through geological time of the three environmental realms – the terrestrial and oceanic realms, and the shallow seas spilling across the continental margins, the neritic realm, in between. His main focus in recent years has been the geological record of southern Australia, a locale that has had the front-row seat witnessing the birth and development of the Southern Ocean, engine room of the cooling planet during the Cenozoic Era. © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information Biostratigraphy Microfossils and Geological Time BRIAN MCGOWRAN The University of Adelaide © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, Sao Paulo CAMBRIDGE UNIVERSITY PRESS The Edinburgh Building, Cambridge CB2 2RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9780521837507 # Cambridge University Press 2005 This publication 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 2005 Printed in the United Kingdom at the University Press, Cambridge A record for this publication is available from the British Library ISBN-13 978-0-521-83750-7 hardback ISBN-10 0-521-83750-2 hardback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information For the six women in my inner universe: Fiona, Heidi, Lisi, Rosi, Jasmine and Susi © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information Contents Preface xi Acknowledgments xix 1 Biogeohistory and the development of classical biostratigraphy 1 Summary 1 Introduction 1 Significance of fossils 3 Zones and zonation through a century 8 2 The biostratigraphy of fossil microplankton 19 Summary 19 Introduction 19 An ascending conceptual series in planktonic zones 21 Planktonic foraminifera in the Caucasus 22 The Trinidad connection 25 From assemblage zones to range zones 28 From range zones to phylozones 29 Coping with provinciality 33 Towards the chronozone 36 Datums 38 Cross-correlation, calibration and quality control 42 Correlations in the Austral Palaeogene 46 3 Biostratigraphy: its integration into modern geochronology 47 Summary 47 Arcane initials aplenty: the CTS, the GPTS and the IMBS 47 Homotaxy and diachrony 54 Biostratigraphy and cyclostratigraphy 65 vii © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information viii Contents 4 Biostratigraphy and biohistorical theory I: evolution and correlation 85 Summary 85 Two approaches to evolutionary theory 85 Micropalaeontology and biostratigraphy: preconceptions and practice 86 The thoughts of Martin Glaessner 88 Planktonic foraminifera in correlation: bioentities or biocharacters? 91 Planktonic foraminifera: biogeography and stratification 105 Planktonic foraminifera and stable isotopes 108 Planktonic foraminifera and molecular systematics 114 Speciation in biostratigraphically important lineages 117 Stage of evolution: the larger foraminifera 134 Stage of evolution: the Cenozoic mammals 147 The tensions in biostratigraphy: can the species survive? 152 Concluding comments: evolution and biochronology 158 5 Systemic stratigraphy: beyond classical biostratigraphy 164 Summary 164 Systemic stratigraphy 164 Biostratigraphy of reversible events and high-resolution biostratigraphy 166 Sequence biostratigraphy 176 6Biostratigraphy and biohistorical theory II: carving Nature at the joints 205 Summary 205 Hierarchy, tiering and the scales of time and life 205 Are there natural biostratigraphic units? 214 Cenozoic chronofaunas of Tethyan neritic foraminifera 227 On the durations of Cenozoic biozones and biochrons 244 Why are good index fossils, good index fossils? 248 Taxic stratigraphic ranges and quantified biostratigraphy 263 7 Biostratigraphy and chronostratigraphic classification 271 Summary 271 Introduction: why do we need a geological timescale? 271 What is a stage? 277 Microfossils and stages 282 Concurrent boundaries in a nested hierarchy? 284 Microplankton and classical stages 286 Where is the Cretaceous–Palaeogene boundary? 291 Where is the Paleocene–Eocene boundary? 297 Where is the Eocene–Oligocene boundary? 300 © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information Contents ix Where is the Palaeogene–Neogene boundary? 305 Where is the Miocene–Pliocene boundary? 310 Where is the Pliocene–Pleistocene boundary? 312 Regional timescales 312 Depositional sequences and regional stages 336 Conclusion: on fossils and time 339 8 On biostratigraphy and biogeohistory 346 Summary 346 The idea of Earth history 346 But is it history? 355 ‘Consilience of inductions’ 360 Another voice: hermeneutics rides again 364 Early biostratigraphy: theory-free? 366 Species and biostratigraphy 369 On the ‘species problem’ 372 Species as individuals 377 The change in world view 383 Finale: the three central concerns of biostratigraphy 394 References 397 Index 447 © Cambridge University Press www.cambridge.org Cambridge University Press 0521837502 - Biostratigraphy: Microfossils and Geological Time Brian McGowran Frontmatter More information Preface Some geologists and palaeontologists recount their awakenings as occurring while collecting minerals and rocks, or when suddenly seeing – really seeing – fossils in rocks for the first time. Others chose geology to fill in the fourth subject in first-year science, as not much more than a happy accident. Many of the teachers at my high school were of the Depression generation for whom teaching was the main career option before the war, and some were indeed excellent in the mathematics-science area. But becoming a successful junior cricketer was more important to me than becoming a scientist. In those days science for the A-stream comprised physics, chemistry and maths, all of which held some interest for me, but that was all. Botany or physiology were for girls, and evolutionary biology and geological time remained as much a shrouded mystery for my generation as it was for our otherwise well-educated antecedents. I came upon W. W. Norton’s Physical Geology (1915) by chance at the age of 16 – it had belonged to an aunt who did Geology I with Douglas Mawson – and I became entranced with theories of the landscape and its history which, together with other natural history and human history, were quite absent from my formal education. When I should have been studying for the public exams, I was digging around in the geology section of the Adelaide public library. Without being very self-aware about it, I was groping towards the realization that Earth and life evolution
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