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Micropaleontology Micropaleontology Pratul Kumar Saraswati • M.S. Srinivasan Micropaleontology Principles and Applications Pratul Kumar Saraswati M.S. Srinivasan Department of Earth Sciences Department of Geology Indian Institute of Technology Bombay Banaras Hindu University Mumbai , India Varanasi , India ISBN 978-3-319-14573-0 ISBN 978-3-319-14574-7 (eBook) DOI 10.1007/978-3-319-14574-7 Library of Congress Control Number: 2015959078 Springer Cham Heidelberg New York Dordrecht London © Springer International Publishing Switzerland 2016 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. 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. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. Printed on acid-free paper Springer International Publishing AG Switzerland is part of Springer Science+Business Media (www.springer.com) Pref ace Microfossils have been mentioned as early as the fi fth century BC by Herodotus, who travelled to Egypt and noted large size foraminifer Nummulites in the pyra- mids. The history of the study of microfossils since then has seen some major turn- ing points; the major ones being the invention of the microscope in the late seventeenth century, followed by the voyage of HMS Challenger (1872–1876) - the fi rst global marine research expedition, increased activity in exploration of oil after the second world war (1939–1945), and the voyage of the Glomar Challenger by an international initiative to core deep-sea sediments (Deep Sea Drilling Project, 1968). The development of micropaleontology through these years has unequivo- cally established the multidimensional applications of microfossils in solving prob- lems in Earth Science. The oil industry nurtured it since the twentieth century and its core application in subsurface stratigraphy continues in spite of commendable development in geophysical logging and seismic methods to interpret subsurface geology. In fact, micropaleontology has expanded its role by being indispensable in seismic calibration, sequence stratigraphy, and as a tool to guide horizontal drilling of the reservoirs to save the cost of production. The Deep Sea Drilling Project and its successors revealed another dimension of micropaleontology by providing vital information about ocean currents, deep-sea processes and paleoclimates of the past. Microfossils thus became an integral part of the newly developed fi eld of paleoceanography. It may not be inappropriate to say that among the various tracers of earth history, microfossils provide a wealth of information including the evolu- tion of life, age and paleoenvironment of sedimentary strata, paleoclimate and paleoceanography. The multiple applications of microfossils attract students and professionals of various backgrounds to employ microfossils in their research. The subject is usually taught at the postgraduate levels of universities, and it is expected that the student has a basic understanding of the principles of paleontology. Most textbooks gener- ally focus on principles of paleontology in reference to mega invertebrate fossils. However, several issues regarding sample collection, taphonomy, biomineralization and ecological details that are unique to microfossils also need to be explored and described. Keeping this in mind, Part I of the textbook addresses the basic principles v vi Preface of micropaleontology with examples of microfossils so that those who don’t have a formal background in paleontology can also develop an understanding of the sys- tematic approach to the study of microfossils. It is important to be aware of the strengths and limitations of microfossils and their geological records. Part II gives an overview of the major groups of microfossils including their morphology, ecology and geologic history. Marine microfossils, particularly foraminifera, are discussed in greater detail compared to other groups as they continue to play a major role in most scientifi c investigations. Part III of the book explains the applications of microfossils in biostratigraphy, paleoenvironmental interpretation and paleoclimate reconstruc- tion, basin analysis for hydrocarbon exploration and paleoceanography. We gratefully acknowledge and thank our colleagues and students who have contributed in various ways in preparing the book: Santanu Banerjee, Anupam Ghosh, Sonal Khanolkar, Asmita Singh, Arundeo Singh, Jyoti Sharma, Ajai Rai, C. N. Ravindran, Jahnavi Punekar, Johann Hohenegger and Komal Verma. Thanks are due to Pradeep Sawant who drafted all the illustrations. We thank Sherestha Saini, Editor, Springer Science + Business Media, for initiating the proposal and bringing it to its conclusion. P.K.S. owes more than formal thanks to Indian Institute of Technology, Bombay for providing the academic freedom to work and granting a sabbatical to write the book. M.S.S. expresses his gratitude to Banaras Hindu University for enabling him to carry out continued research in micropaleontology. P. K. Saraswati M. S. Srinivasan Contents Part I Principles 1 Introduction .............................................................................................. 3 1.1 Introduction ....................................................................................... 3 1.2 Major Groups of Microfossils ........................................................... 4 1.3 Collection of Samples ....................................................................... 7 Outcrop Samples ............................................................................... 7 Subsurface Samples .......................................................................... 8 Deep Sea Drilling Core Samples....................................................... 10 Recent Samples ................................................................................. 10 1.4 Separation of Microfossils from Matrix ............................................ 12 Calcareous Microfossils .................................................................... 12 Calcareous Nannoplankton ............................................................... 15 Siliceous Microfossils ....................................................................... 15 Phosphatic Microfossils .................................................................... 15 Plant Microfossils.............................................................................. 16 1.5 Preparation of Specimens for Scanning Electron Microscopy ........................................................................................ 16 1.6 Sample Preparation for Shell Geochemistry ..................................... 16 References .................................................................................................. 17 2 Taphonomy and Quality of the Fossil Record ....................................... 19 2.1 Introduction ....................................................................................... 19 2.2 Decay of Organic Matter ................................................................... 20 2.3 Post-mortem Transport ...................................................................... 21 2.4 Diagenesis and Dissolution ............................................................... 25 2.5 Time Averaging ................................................................................. 26 2.6 Temporal Resolution and Microstratigraphic Sampling ................... 28 References .................................................................................................. 32 vii viii Contents 3 Microfossil Biomineralization and Biogeochemistry ........................... 35 3.1 Introduction ....................................................................................... 35 3.2 Function of the Shell ......................................................................... 36 3.3 Processes of Biomineralization ......................................................... 37 3.4 Oxygen and Carbon Isotopes in Foraminifera .................................. 42 3.5 Trace Elements in Foraminifera ........................................................ 47 References .................................................................................................. 49 4 Morphology, Taxonomy and Concepts of Species ................................ 53 4.1 Introduction ....................................................................................... 53 4.2 Quantifying Morphology .................................................................. 54 4.3 Taxonomy .......................................................................................... 57 4.4 Cladistic Analysis ............................................................................
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