Geological maps: An Introduction
A recent national survey of geology students indicated that, In a subject so fundamental and yet so varied, every although they saw the need for a basic training in map geologist will have his own views on geological maps - the work, the three-dimensiona
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Geological maps: AN INTRODUCTION
Alex Maltman
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VAN NOSTRAND REINHOLD
~ _ _ _ _ New York
First published in 1990 by Open University Press Celtic Court 22 Ballmoor Buckingham MK18 lXW Copyright © Alex Maltman 1990 Softcover reprint of the hardcover 1st edition 1990 All rights reserved. No part of this work covered by the copyright hereon may be reproduced or used in any form or by by any means - graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems - without written permission from the publisher. U.S.A. Edition Library of Congress Catalog Card Number 90-11913 ISBN-13: 978-1-4684-6664-5 e-ISBN-13: 978-1-4684-6662-1 DOl: 10.1 007/978-1-4684-6662-1 Van Nostrand Reinhold 115 Fifth Avenue New York, New York 10003 Nelson Canada 1120 Birchmount Road Scarborough, Ontario MIK 5G4, Canada 16
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Library of Congress Cataloging-in-Publication Data Maltman, Alex, 1944Geological maps: an introduction/by Alex Maltman. p. cm. Includes bibliographical references. ISBN-13: 978-1-4684-6664-5 1. Geological mapping. 2. Geology - Maps. 1. Title. OE36.M33 1990 550' .22'3-dc20 90-11913 CIP
Contents
Foreword 1 Some fundamentals of geological maps 1.1 Introduction 1.2 The topographic base map 1.2.1 Scale 1.2.2 Map projection 1.2.3 Grid systems and location 1.2.4 Relief 1.2.5 Key or legend 1.3 Geological aspects 1.3.1 Key or legend 1.3.2 Superficial and bedrock maps 1.3.3 The third dimension: geological cross-sections 1.3.4 The interpretive nature of maps 1.3.5 Aesthetics 1.4 Summary chapter 1.5 Selected further reading
2 The nature of geological maps: the Ten Mile map of the UK and the 1 : 2 500 000 map of the USA 2.1 Introduction: cartographic matters 2.2 Interpretation of the maps: geology and relief 2.3 Map patterns and geological structure 2.3.1 Dipping formations 2.3.2 Unconformities 2.3.3 Folded rocks 2.3.4 Faulted rocks 2.3.5 Igneous rocks and geological histories 2.4 Conclusion 2.5 Summary of chapter 3 The three-dimensional aspect: structure contours 3.1 Introduction 3.2 The nature of structure contours 3.3 Examples of structure contours on maps
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Structure contours derived from borehole/well information 3.5 Structure contours derived from topography: the theory 3.6 Structure contours derived from topography: the practice 3.7 Structure contours from topography and boreholes 3.8 Straight structure contours 3.9 Summary of chapter 3.10 Selected further reading 3.4
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4 Measurements in three dimensions: strike and dip, formation thickness and depth 4.1 Introduction 4.2 Strike and dip 4.3 Apparent dip 4.4 Formation thickness 4.5 Formation depth 4.6 The 'three-point' method 4.7 Summary of chapter 4.8 Selected further reading
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5 Geological cross-sections 5.1 Introduction 5.2 Line of section 5.3 Scale and vertical exaggeration 5.4 Manual drawing of cross-sections 5.5 Structure and stratigraphic s