PHANEROZOIC EVOLUTION OF NORTH AMERICAN CONTINENT- OCEAN TRANSITIONS 1. Proterozoic N. America, little deformed in Phanerozoic 2. Proterozoic N. America, deformed in Phanerozoic ancient displaced terranes 4. displacing terranes n 5. oceanic lithosphere \ \ > Explorer Juan de Fuca Rivera PI passive and other inactive margins active margin era, n 5 Summary Volume to Accompany the DNAG Continent-Ocean Transect Series Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 The Decade of North American Geology Summary Volume to Accompany the DNAG Continent-Ocean Transect Series Phanerozoic Evolution of North American Continent-Ocean Transitions Edited by Robert C. Speed Department of Geological Sciences Northwestern University Evanston, Illinois 60208 1994 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 Acknowledgment Publication of this volume, one of the synthesis volumes of The Decade of North American Geology Project series, has been made possible by members and friends of the Geological Society of America, corporations, and government agencies through contributions to the Decade of North American Geology fund of the Geological Society of America Foundation. Following is a list of individuals, corporations, and government agencies giving and/or pledging more than $50,000 in support of the DNAG Project: Amoco Production Company Pennzoil Exploration and Production ARCO Exploration Company Company Chevron Corporation Phillips Petroleum Company Cities Service Oil and Gas Company Shell Oil Company Conoco, Inc. Caswell Silver Diamond Shamrock Exploration Standard Oil Production Company Corporation Oryx Energy Company (formerly Exxon Production Research Company Sun Exploration and Production Getty Oil Company Company) Gulf Oil Exploration and Production Superior Oil Company Company Tenneco Oil Company Paul V. Hoovler Texaco, Inc. Kennecott Minerals Company Union Oil Company of California Kerr McGee Corporation Union Pacific Corporation and Marathon Oil Company its operating companies: Maxus Energy Corporation Union Pacific Resources Company McMoRan Oil and Gas Company Union Pacific Railroad Company Mobil Oil Corporation Union Pacific Realty Company Occidental Petroleum Corporation U.S. Department of Energy © 1994 by The Geological Society of America, Inc. Library of Congress Cataloging-in-Publication Data All rights reserved. Phanerozoic evolution of North American continent-ocean transitions / All materials subject to this copyright and included edited by Robert C. Speed, in this volume may be photocopied for the noncommercial p. cm. purpose of scientific or educational advancement. At head of title: The Decade of North American Geology summary volume to accompany the DNAG continent-ocean transect series. ISBN 0-8137-5305-8 Copyright is not claimed on any material prepared 1. Geology, Structural—North America. 2. Continental margins- by government employees within the scope of their -North America. 3. Plate tectonics—North America. 4. Earth- employment. -Crust. I. Speed, Robert C. II. Decade of North American Geology Project. Published by The Geological Society of America, Inc. QE626.P48 1994 3300 Penrose Place, P.O. Box 9140, Boulder, Colorado 80301 551.7'0097—dc20 94-15452 CIP Printed in U.S.A. Cover Photo: Map of North America showing the locations of the continent-ocean transects discussed in this volume. 10 987654321 ii Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 Contents Preface v Foreword vii NORTH AMERICAN TRANSITIONS AS A WHOLE 1. North American continent-ocean transitions over Phanerozoic time 1 R. C. Speed EASTERN NORTH AMERICA 2. Transects of the ancient and modern continental margins of eastern Canada 87 R. T. Haworth, C. E. Keen, and H. Williams 3. Continental margin of the eastern United States: Past and present 129 D. W. Rankin SOUTHERN NORTH AMERICA 4. Crustal structure and evolution of the southeastern margin of North America and the Gulf of Mexico basin 219 R. T. Buffler and W. A. Thomas 5. Phanerozoic tectonic evolution of Mexico 265 F. Ortega-Gutiérrez, R. L. Sedlock, and R. C. Speed WESTERN NORTH AMERICA 6. Synopsis of geologic history portrayed along Corridor C-3: Southern California borderland-Rio Grande rift 307 D. G. Howell and J. G. Vedder 7. Tectonic evolution of the central U.S. Cordillera: A synthesis of the CI and C2 Continent-Ocean Transects 315 J. B. Saleeby, R. C. Speed, and M. C. Blake 8. Continent-ocean transitions in western North America between latitudes 46 and 56 degrees: Transects Bl, B2, B3 357 J.W.H. Monger, R. M. Clowes, D. S. Cowan, C. J. Potter, R. A. Price, and C. J. Yorath iii Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 iv Contents NORTHERN NORTH AMERICA 9. Continent-ocean transition in Alaska: The tectonic assembly of eastern Denalia 399 T. E. Moore, A. Grantz, and S. M. Roeske 10. The polar continent-ocean transition in Canada (Corridor G) 443 J. F. Sweeney, U. Mayr, L. W. Sobczak, and H. R. Balkwill TOPICAL SYNTHESES 11. Rifted continental margins of North America 453 D. S. Sawyer 12. Modern active oceanic margins of North America All R. von Huene and R. Riddihough Index 489 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 Preface The Geology of North America series has been prepared to mark the Centennial of The Geological Society of America. It represents the cooperative efforts of more than 2,000 individuals from academia, state and federal agencies of many countries, and industry to prepare syntheses that are as current and authoritative as possible about the geology of the North American continent and adjacent oceanic regions. This series is part of the Decade of North American Geology (DNAG) Project, which also includes six wall maps at a scale of 1:5,000,000 that summarize the geology, magnetic and gravity anomaly patterns, regional stress fields, thermal aspects, and seismicity of North America and its surroundings. Together, the synthesis volumes and maps are the first co- ordinated effort to integrate all available knowledge about the geology and geophysics of a crustal plate on a regional scale. The products of the DNAG Project present the state of knowledge of the geology and geophysics of North America through the 1980s, and they point the way toward work to be done in the decades ahead. A. R. Palmer General Editor for the volumes published by The Geological Society of America J. O. Wheeler General Editor for the volumes published by the Geological Survey of Canada v Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/3733245/9780813754437_frontmatter.pdf by guest on 28 September 2021 Foreword The focus of this book is the structure and Phanerozoic others; Monger and others; Moore and others); and northern or evolution of the transitional region of the North American conti- Arctic margin (Moore and others; Sweeney and others). nent between its craton and bordering oceanic lithospheres It has become evident in recent years, as discussed in these (Fig. 1). The geological continent of North America here con- chapters, that heterogeneity is much greater than previously rec- sidered includes Canada, the United States except for Hawaii, ognized; that long-distance correlations among rocks, structures, Mexico, and northern Central America. The transitional region is and events are commonly wrong or controversial; and that obli- the part of North America that is peripheral to the craton (zones quity of velocity relative to the strike of the plate boundary zone 2-4, Fig. 1) and has undergone tectonism within a plate bound- is the rule. Nonetheless, the long-recognized diversity of Phaner- ary zone at one or more times in the Phanerozoic. The transi- ozoic evolution among North American margins survives new tional regions that are now active margins provide an understand- data and analysis, and such differences are here employed in a ing of tectonic phenomena that is highly resolved but of short hemispheric synthesis. observational period. In contrast, the ancient margins of North Besides the chapters with tectonic-geographic bases, this America—passive, active, and collisional—provide a long-term book contains topical chapters on modern active and passive tectonic record although one of low resolution in time and space. margins of North America (Von Huene; Sawyer). These synthe- The objectives of this book are an up-to-date synthesis of the size the recent findings of the processes and structures created at main structures in and sequences of passive, active, and collisional modern continent-ocean transitions. margins around Phanerozoic North America; its 600 m.y. history Finally, a chapter on the Phanerozoic continent-ocean tran- of growth and attrition; and interpretations of the processes of sitions of North America as a whole (Speed) offers an attempt to plate boundary tectonics. encapsulate the interactions, similarities, and differences