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Seismic Sea Waves Tsunamis n c Bulletins are designed to interpret current knowledge in scientific fields pertinent to Canadian fisheries and aquatic environments. The Journal of the Fisheries Research Board of Canada is published in annual volumes of monthly issues and Miscellnneous Special Publications are issued periodically. These series are for sale by Supply and Services Canada, Printing and Publishing, Ottawa, KIA OS9. Remittances must be in advance, payable in Canadian funds to the order of the Receiver General for Canada. Ediforand J. C. STEVENSON, PH.D. of Scientific Information Deputy Editor J. WATSON, PH.D. Assis fanf Editors JOHANNA M. REINHART, M.SC. D. G. COOK, PH.D. Production-Documen fation J. CAMP G. J. NEVILLE MONASMITH MICKEYLEWIS Department of Fisheries and the Environment Fisheries and Marine Service Scientific Information and Publications Branch Ottawa, Canada KIA OE6 BULLETIN 198 (La version franqaise est en preparation) SEISMIC SEA WAVES TSUNAMIS T. S. MURTY' Marine Environmental Data Services Brunch Fisheries and Marine Service Department of Fisheries und the Environment Ottawa, Canada DEPARTMENT OF FISHERIES AND THE ENVIRONMENT FISHERIES AND MARR\JE SERVICE Ottawa 1977 Vice-chairman. Tsunami Committee. International Union of Geodesy and Geophysics 0 Minister of Supply and Services Canada 1977 Available by mail from: Printing and Publishing Supply and Services Canada Ottawa. Canada KIA OS9 or through your bookseller A deposit copy of this publication is also available for reference in public lihrairies across Canada Canada: $10.00 Catalog No. Fs 94- 198 Other countries: $12.00 ISBN 0-660-00565-4 ISSN 0068-7537 Price subjecr io change wirhour nolic~ OtPdWa Dust jacket and cover designed by Christine Rusk Printed by D. W. Friesen & Sons Ltd. Altona. Manitoba. Canada Contract No. OKX6-09112 Printed in Canada 1977 Contents PREFACE........................................................................................................................ vii ABSTRACT/&SUM~ ...................................................................................................... ix INTRODUCTION............................................................................................................ 1 CHAPTER1. DISPERSIONAND INITIALVALUE PROBLEM 1.1 Dispersion .................................................................................................... 3 1.2 The Cauchy-Poisson problem ..... ................................................ 14 CHAPTER2 . TSUNAMIGENERATION 2.1 Tsunami-earthquake energy relations, source areas .............................. 31 2.2 Tsunami generation by earthquakes ................................................... 42 2.3 Tsunami generation by nonseismic causes .............................................. 47 2.4 Inverse tsunami problem ............................................ 58 2.5 Laboratory experiments ............................................ 63 CHAPTER3 . TSUNAMIPROPAGATION 3.1 Refraction. diffraction. and scattering ................. ................................ 75 3.2 Trapping wave energy ........................................... ................................ 94 3.3 Tsunami propagation ................................................................................ 117 3.4 Laboratory experiments ............................................................................ 139 CHAPTER4 . COASTALPROBLEMS 4.1 Resonance ............... .......................................................................... 145 4.2 Coastal phenomena . .............................................. 167 4.3 Tsunami response and inundation of specific water bodies .................... 189 4.4 Laboratory experiments ............................................................................ 201 CHAPTER5 . GLOBALTSUNAMIS 5.1 Tsunamis in Japan, USSR, Australia, and New Zealand ........................ 215 5.2 Tsunamis in the Pacific Islands, Aleutians, and Alaska .......................... 235 5.3 Tsunamis in South and North America (excluding Alaska) .................. 259 5.4 Tsunamis in the Atlantic Ocean, Europe, Middle East, and Asia .......... 268 CHAPTER6 . TSUNAMIWARNING SYSTEMS PAST, PRESENT, AND FUTURE 6.1 Seismic and tsunami instrumentation ...................................................... 281 6.2 Tsunami protection measures .................................................................... 286 6.3 Tsunami warning systems ofthe past and present .................................. 289 6.4 Acoustic and internal gravity waves in the atmosphere ................ 6.5 Atmospheric nuclear explosions ........................ .............................. 308 6.6 Atmospheric disturbances generated by earthquakes and volcanic explosions ............................................................ ................................. 312 V Contents (concluded) REFERENCES............... ......................................................................................... 3 19 APPENDIXA . SEISMOLOGY(microfiche in pocket) A . 1 Structure of the earth and the new global tectonics ................................ 1 A.2 Seismic waves and concepts of intensity and magnitude ........................ 4 A.3 Epicenter determination and travel-time curves .................................... 10 A.4 Earthquake mechanism ............................................................................ 19 ... AS Regional seismicity .................................................................................... 29 A.6 Earthquake prediction and control .......................................................... 35 vi Preface This book represents my attempt to synthesize current knowledge on tsunamis. To keep it small, it was necessary to omit most of the early work on tsunamis. The book is written primarily for oceanographers and assumes a knowledge of hydrodynamics, especially water waves. I attempted to utilize a uniform mathema- tical notation throughout but some repetition of English and Greek symbols was unavoidable. Because of this repetition, it was felt that inclusion of a table of mathematical symbols would serve no purpose and the symbols, where they appear, are fully explained. The introduction gives a brief nonmathematical description of the various aspects of the tsunami problem. Section 1.1 introduces the so-called “Ursell param- eter” to determine under what conditions phase and amplitude dispersions are important. In Section 1.2 the classical Cauchy-Poisson problem in dealing with water waves generated from an initial perturbation is introduced. Chapter 2 discusses the tsunami generation by earthquakes, volcanic eruptions, and nuclear explosions. In Chapter 3 problems related to the propagation of tsunamis in the oceans, trapping of long waves by islands, and related problems such as refraction, diffraction, and scattering, are discussed. Chapter 4 deals with the coastal aspects of tsunamis, namely tsunami forerunner, tsunami bore, initial withdrawal of water, secondary undulation, tsunami response and inundation, and such related topics as resonance, Helmholtz mode, and radiation stress. The laboratory experiments on tsunami generation, propagation, and coastal problems have been included in Chapters 2, 3, and 4, respectively. Chapter 5 describes tsunamis in various regions on the globe: Japan, USSR, Australia, New Zealand, Hawaii, other Pacific Islands, Aleutians, Alaska, South and North America, Atlantic Ocean, Europe, Middle East, and Asia. Seismic and tsunami instrumentation is described in Section 6.1. Tsunami protection measures and warning systems of the past and present and sociological problems are treated, respectively, in Sections 6.2 and 6.3. Sections 6.4 to 6.6 deal with the concept of acoustic and internal gravity waves in the atmosphere, and disturbances in the atmosphere generated by earthquakes, tsunamis, volcanic explosions, and nuclear tests. The concept of the ionospheric detection of tsunamis is fairly new, looks promising, and is included. Required background information on seismology appears in the Appendix (in microfiche form). In this, topics such as structure of the earth, new global tectonics, concepts of earthquake intensity and magnitude, epicenter determination, travel-time curves, regional seismicity, and earthquake prediction and control are briefly discussed. vii I thank Drs N. J. Campbell and J. R. Wilson of the Marine Sciences and Information Directorate, Fisheries and Marine Service, Department of Fisheries and the Environment, for providing the facilities to carry out this work, and my colleague Mr F. G. Barber for his help and guidance throughout. Professor Paul H. Leblond of the University of British Columbia reviewed the manuscript and offered many constructive suggestions. Mrs R. Chawla helped with the library research and Mrs Margaret Johnstone did all the necessary typing, including the equations. I thank the following societies and associations for granting me permission to reproduce material from their publications : American Geophysical Union; American Institute of Physics; American Mathematical Society; American Associa- tion for the Advancement of Science; American Journal of Science; American Society of Civil Engineers; Cambridge University Press, New York; Clarendon Press, Oxford, U.K.; D. Reidel Publishing Company, Dordrecht, Netherlands; Earthquake Research Institute, Tokyo; East-West Center Press, Honolulu; European Seismologi- cal Commission; Geophysics - Journal of the Society of Exploration Geophysicists; Hawaii Institute of Geophysics;
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