Geology of Southeast Alaska: Rock and Ice in Motion

154 Pages·2006·2.79 MB·English

by  Harold Stowell

GEOLOGY / NATURE
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The most powerful forces on earth have e
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shaped the landscape of Southeast Alaska.
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Scientists and visitors from around the world t

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trek north to experience wild rivers, powerful
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glaciers, and breathtaking mountain peaks. a
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Now, for the fi rst time, a handy guide to the k
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region is available. Complete with color illus-

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trations revealing millions of years of geologi- O
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cal history and in-depth descriptions of Sitka, K

Juneau, and Glacier Bay, Geology of Southeast A
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Alaska is essential reading for anyone fasci- D

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nated by rock and ice in motion. C
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Harold H. Stowell is professor of geology M
at the University of Alabama. He began his O
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career in 1979 as an exploration geologist IO
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and received his doctorate from Princeton

University in 1987. Dr. Stowell‘s fi eldwork has S
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taken him to Alaska and Canada, as well as to O
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New Zealand, Antarctica, and Svalbard. He is a E
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fellow of the Geological Society of America. L

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Geology of Southeast Alaska
Rock and Ice in Motion
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Geology of Southeast Alaska
Rock and Ice in Motion
Harold H. Stowell
University of Alaska Press
Fairbanks
© 2006 University of Alaska Press
P.O. Box 756240
Fairbanks, AK 99775-6240
Printed in China
This publication was printed on paper that meets the minimum
requirements for ANSI/NISO x39.48-1992 (Permanence of Paper).
ISBN 13: 978-1-889963-81-5
ISBN 10: 1-889963-81-X
Library of Congress Cataloging-in-Publication Data
Stowell, Harold Hilton.
Geology of southeast Alaska : rock and ice in motion / Harold H. Stowell.
p. cm.
Includes bibliographical references.
ISBN-13: 978-1-889963-81-5 (pbk. : alk. paper)
ISBN-10: 1-889963-81-X (pbk. : alk. paper)
1. Geology—Alaska, Southeast. 2. Glaciers—Alaska, Southeast.
3. Plate tectonics—Alaska, Southeast. 4. Climate—Alaska, Southeast. I. Title.
QE84.S68S76 2006
557.982—dc22
2005027066
All illustrations by Harold H. Stowell unless otherwise noted.
Cover and interior text design by Dixon J. Jones, UAF Rasmuson Library Graphics
Book production by Sue Mitchell
Cover image: the Fairweather Range; the terminus of Brady Glacier is visible at the
base of the mountains.
Back cover images: (top) sea arch on Kuiu Island; (center) infrared aerial photo-
graph of Margerie, Ferris, and Grand Pacifi c glaciers; (bottom) glacial grooves cut
into the Coast Plutonic Complex sill along the south shore of Tracy Arm. Sun and
glacial silt produce the intense blue-green water color.
To those who contribute
to understanding the geology
and to preserving the unique environment
of Southeast Alaska and especially to Kim Ouderkirk,
who provided moral and physical support
throughout the research and writing of this book.
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Table of Contents
Acknowledgments ix
Introduction xi
1 Geography of Southeast Alaska 1
2 Glaciers, Ice Ages, and Global Change 7
3 Plate Tectonics: A Geologic Paradigm 23
4 Rock Types: Classifi cation of Earth Materials 33
5 Faults, Earthquakes, and Mountain Building 39
6 The Alexander Archipelago 45
7 The Coast Mountains: Exhumed Lower Crust 53
8 Regional Geology 59
Notes 110
Glossary of Geological Terms 113
Bibliography 127
Index 134
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