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J^ationaC Academy Press The National Academy Press was created by the National Academy of Sciences to publish the reports issued by the Academy and by the National Academy of Engineering, the Institute of Medicine, and the National Research Council, all operating under the charter granted to the National Academy of Sciences by the Congress of the United States.
REFERENCE COPY FOR LIBRARY USE CNtY STUDIES IN GEOPHYSICS Explosive Volcanism: Inception, Evolution, and Hazards Geophysics Study Committee Geophysics Research Forum Commission on Physical Sciences, Mathematics, and Resources National Research Council NAS-NAE NATIONAL ACADEMY PRESS 1AM O 0 1PP4 Washington, D.C. 1984 LIBRARY
NATIONAL ACADEMY PRESS 2101 Constitution Avenue, NW Washington, DC 20418 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the Councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for this report were chosen for their special competences and with regard for appropriate balance. This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The National Research Council was established by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and of advising the federal government. The Council operates in accordance with general policies determined by the Academy under the authority of its congressional charter of 1863, which establishes the Academy as a private, nonprofit, self-governing membership corporation. The Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in the conduct of their services to the government, the public, and the scientific and engineering communities. It is ad- ministered jointly by both Academies and the Institute of Medicine. The National Academy of Engineering and the Institute of Medicine were established in 1964 and 1970, respectively, under the charter of the National Academy of Sciences. The Geophysics Study Committee is pleased to acknowledge the support of the National Science Foundation, the Defense Advanced Research Projects Agency, the National Aeronautics and Space Administration, the National Oceanic and Atmospheric Administration, the U.S. Geological Survey, and the U.S. Department of Energy (Grant # DE-FGO1-82ER12018) for the conduct of this study. Library of Congress Cataloging in Publication Data Main entry under title: Explosive volcanism. (Studies in geophysics) 1. VolcanismâAddresses, essays, lectures. I. National Research Council (U.S.). Geophysics Study Committee. II. Series. QE522.E97 1984 551.2'1 83-23610 ISBN 0-309-03393-4 Printed in the United States of America
Panel on Explosive Volcanism FRANCIS R. BOYD, JR., Carnegie Institution of Washington, Chairman ARTHUR L. BOETTCHER, University of California, Los Angeles LAWRENCE W. BRAILE, Purdue University RICHARD W. CARLSON, Carnegie Institution of Washington ROBERT L. CHRISTIANSEN, U.S. Geological Survey, Menlo Park ROBERT W. DECKER, U.S. Geological Survey, Hawaii National Park RICHARD S. FISKE, Smithsonian Institution SUSAN WERNER KIEFFER, U.S. Geological Survey, Flagstaff ROBERT G. LUEDKE, U.S. Geological Survey, Reston BRUCE D. MARSH, The Johns Hopkins University ROBERT G. McQUEEN, Los Alamos National Laboratory JAMES G. MOORE, U.S. Geological Survey, Menlo Park CARL J. RICE, The Aerospace Corporation I. SELWYN SACKS, Carnegie Institution of Washington LEE SIEBERT, Smithsonian Institution TOM SIMKIN, Smithsonian Institution ROBERT B. SMITH, University of Utah ROBERT L. SMITH, U.S. Geological Survey, Reston KENNETH H. WOHLETZ, Los Alamos National Laboratory iii
Geophysics Study Committee* ARTHUR E. MAXWELL, University of Texas at Austin, Chairman COLIN BULL, Ohio State University JOHN C. CROWELL, University of California, Santa Barbara NICHOLAS C. MATALAS, U.S. Geological Survey, Reston J. MURRAY MITCHELL, National Oceanic and Atmospheric Administration V. RAMA MURTHY, University of Minnesota RAYMOND G. ROBLE, National Center for Atmospheric Research FERRIS WEBSTER, University of Delaware Liaison Representatives BRUCE B. HANSHAW, U.S. Geological Survey, Reston GEORGE A. KOLSTAD, U.S. Department of Energy MICHAEL MAYHEW, National Science Foundation NED OSTENSO, National Oceanic and Atmospheric Administration WILLIAM RANEY, National Aeronautics and Space Administration CARL F. ROMNEY, Defense Advanced Research Projects Agency Staff THOMAS M. USSELMAN 'Members of the Geophysics Study Committee whose terms expired in June 1982 but who were involved in initiating this study are CHARLES L. DRAKE, Dartmouth College, Chairman, LOUIS J. BATTAN, University of Arizona, Vice- Chairman, JOHN D. BREDEHOEFT, U.S. Geological Survey, Menlo Park; ALLAN V. COX, Stanford University; HUGH ODISHAW, University of Arizona; CHARLES B. OFFICER, Dartmouth College. IV
Geophysics Research Forum DON L. ANDERSON, California Institute of Technology, Chairman CHARLES R. BENTLEY, University of Wisconsin JAMES H. COULSON, Tennessee Valley Authority WILLIAM R. DICKINSON, University of Arizona THOMAS DONAHUE, University of Michigan JOHN V. EVANS, Communications Satellite Corporation HOWARD R. GOULD, Exxon Production Research Company DEVRIE S. INTRILGATOR, Carmel Research Center KEITH A. KVENVOLDEN, U.S. Geological Survey, Menlo Park THOMAS F. MALONE, West Hartford, Connecticut ARTHUR E. MAXWELL, University of Texas at Austin JOHN C. MAXWELL, University of Texas at Austin PAUL W. POMEROY, Rondout Associates, Inc. HUGH ODISHAW, University of Arizona ALAN H. SHAPLEY, National Oceanic and Atmospheric Administration JOHN SLAUGHTER, University of Maryland FRANCIS G. STEHLI, University of Oklahoma MURRAY STRASBERG, U.S. Navy VERNER E. SUOMI, University of Wisconsin, Madison EINAR A. TANDBERG-HANSSEN, National Aeronautics and Space Administration BYRON D. TAPLEY, University of Texas at Austin CHARLES A. WHITTEN, Silver Spring, Maryland Ex Offtcio LOUIS J. BATTAN, University of Arizona OWEN GINGERICH, Smithsonian/Harvard Center for Astrophysics ROBERT HOFSTADTER, Stanford University THOMAS A. SENIOR, University of Michigan Staff PEMBROKE J. HART V
Commission on Physical Sciences, Mathematics, and Resources HERBERT FRIEDMAN, National Research Council, Chairman ELK AN R. BLOUT, Harvard Medical School WILLIAM BROWDER, Princeton University BERNARD F. BURKE, Massachusetts Institute of Technology HERMAN CHERNOFF, Massachusetts Institute of Technology WALTER R. ECKELMANN, Sohio Petroleum Company JOSEPH L. FISHER, Office of the Governor, Commonwealth of Virginia JAMES C. FLETCHER, University of Pittsburgh WILLIAM A. FOWLER, California Institute of Technology GERHART FRIEDLANDER, Brookhaven National Laboratory EDWARD A. FRIEMAN, Science Applications, Inc. EDWARD D. GOLDBERG, Scripps Institution of Oceanography CHARLES L. HOSLER, JR., Pennsylvania State University KONRAD B. KRAUSKOPF, Stanford University CHARLES J. MANKIN, Oklahoma Geological Survey WALTER H. MUNK, University of California, San Diego GEORGE E. PAKE, Xerox Research Center ROBERT E. SIEVERS, University of Colorado HOWARD E. SIMMONS, JR., E. I. du Pont de Nemours & Co., Inc. JOHN D. SPENGLER, Harvard School of Public Health HATTEN S. YODER, JR., Carnegie Institution of Washington RAPHAEL G. KASPER, Executive Director vi
Studies in Geophysics* ENERGY AND CLIMATE Roger R. Revelle, panel chairman, 1977, 158 pp. CLIMATE, CLIMATIC CHANGE, AND WATER SUPPLY James R. Wallis, panel chairman, 1977, 132 pp. ESTUARIES, GEOPHYSICS, AND THE ENVIRONMENT Charles B. Officer, panel chairman, 1977, 127 pp. THE UPPER ATMOSPHERE AND MAGNETOSPHERE Francis S. Johnson, panel chairman, 1977, 169 pp. GEOPHYSICAL PREDICTIONS Helmut E. Landsberg, panel chairman, 1978, 215 pp. IMPACT OF TECHNOLOGY ON GEOPHYSICS Homer E. Newell, panel chairman, 1979, 121 pp. CONTINENTAL TECTONICS B. Clark Burchfiel, Jack E. Oliver, and Leon T. Silver, panel co-chairmen, 1980, 197 pp. MINERAL RESOURCES: GENETIC UNDERSTANDING FOR PRACTICAL APPLICATIONS Paul B. Barton, Jr., panel chairman, 1981, 118 pp. SCIENTIFIC BASIS OF WATER-RESOURCE MANAGEMENT Myron B. Fiering, panel chairman, 1982, 127 pp. SOLAR VARIABILITY, WEATHER, AND CLIMATE John A. Eddy, panel chairman, 1982, 106 pp. CLIMATE IN EARTH HISTORY Wolfgang H. Berger and John C. Crowell, panel co-chairmen, 1982, 198 pp. FUNDAMENTAL RESEARCH ON ESTUARIES: THE IMPORTANCE OF AN INTERDISCIPLINARY APPROACH Charles B. Officer and L. Eugene Cronin, panel co-chairmen, 1983, 79 pp. EXPLOSIVE VOLCANISM: INCEPTION, EVOLUTION, AND HAZARDS Francis R. Boyd, Jr., panel chairman, 1984, 176 pp. 'Published to date. vii
Preface In 1974 the Geophysics Research Board completed a plan, subsequently approved by the Committee on Science and Public Policy of the National Academy of Sciences, for a series of studies to be carried out on various subjects related to geophysics. The Geophysics Study Committee was established to provide guidance in the conduct of the studies. One purpose of the studies is to provide assessments from the scientific community to aid policymakers in decisions on societal problems that involve geophysics. An im- portant part of such an assessment is an evaluation of the adequacy of present geophysical knowledge and the appropriateness of present research programs to provide information required for those decisions. Some of the studies place more emphasis on assessing the present status of a field of geophysics and identifying the most promising directions for future research. This study on explosive volcanism was begun soon after the cataclysmic eruptions of Mount St. Helens. It readily became apparent to the committee that an assessment of the explosive nature of volcanoes must cover all types of volcanic activity; any volcano can be explosive. Consideration of explosive volcanism must start with the generation of magma. Magma-forming processes are intimately connected with tectonics, and there are pronounced differences in the nature of volcanism between regions of compression and subduction and regions of rifting or broader extension. The cyclic and episodic aspects of volcanic activity form a basis for predicting eruptions and can be sources of information on the rates at which magma and energy are introduced to volcanic systems. Improved understanding of the physics of volcanic eruptions is an exciting goal that is vital to progress in hazard evaluation. Finally, the study of explosive volcanism must include an appreciation of the severe social problems that are caused by erupting volcanoes. None is of greater urgency than planning for a crisis. This report considers the progress in research on these aspects of explosive volcanism and the need for additional research efforts. The study was developed through meetings of the Geophysics Study Committee and the Panel on Explosive Volcanism. The preliminary scientific findings of the panel were presented at an American Geophysical Union meeting that took place in San Francisco ix
Preface in December 1981. These presentations and the essays contained in this volume provide examples of current basic knowledge of explosive volcanism. They also pose many of the fundamental questions and uncertainties that require additional research. In com- pleting their papers, the authors had the benefit of discussion at this symposium as well as comments of several scientific referees. Responsibility for the individual essays rests with the corresponding authors. The Overview of the study summarizes the highlights of the essays and formulates conclusions and recommendations. In preparing it, the panel chairman and the com- mittee had the benefit of meetings that took place at the symposium, the comments of the panel of authors, and selected referees. Responsibility for the Overview rests with the Geophysics Study Committee and the chairman of the panel.
Contents OVERVIEW AND RECOMMENDATIONS BACKGROUND 1. The Source Regions of Alkaline Volcanoes Arthur L. Boettcher 13 2. Tectonic Influence on Magma Composition of Cenozoic Basalts from the Columbia Plateau and Northwestern Great Basin, U.S.A. Richard W. Carlson 23 3. Subduction Geometry and Magma Genesis 1. Selwyn Sacks 34 4. Potentially Active Volcanic Lineaments and Loci in Western Conterminous United States Robert L. Smith and Robert G. Luedke 47 5. Mechanics and Energetics of Magma Formation and Ascension Bruce D. Marsh 67 6. Yellowstone Magmatic Evolution: Its Bearing on Understanding Large-Volume Explosive Volcanism Robert L. Christiansen 84 7. Crustal Structure and Evolution of an Explosive Silicic Volcanic System at Yellowstone National Park Robert B. Smith and Lawrence W. Braile 96
Contents 8. Explosive Eruptions in Space and Time: Durations, Intervals, and a Comparison of the World's Active Volcanic Belts Tom Simkin and Lee Siebert 110 9. Explosive Eruptions of Kilauea Volcano, Hawaii Robert W. Decker and Robert L. Christiansen 122 10. Chronology and Character of the May 18, 1980, Explosive Eruptions of Mount St. Helens James G. Moore and Carl J. Rice 133 11. Factors Governing the Structure of Volcanic Jets Susan Werner Kieffer 143 12. Experimental Studies of Hydromagmatic Volcanism Kenneth H. Wohletz and Robert G. McQueen 158 13. Volcanologists, Journalists, and the Concerned Local Public: A Tale of Two Crises in the Eastern Caribbean Richard S. Fiske 170 xn
