The Complex Faulting Process of Earthquakes

Author: J. Koyama
Publisher: Springer Science & Business Media
ISBN: 9401732612
Format: PDF, ePub, Docs
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In seismology an earthquake source is described in terms of a fault with a particular rupture size. The faulting process of large earthquakes has been investigated in the last two decades through analyses of long-period seismo grams produced by advanced digital seismometry. By long-period far-field approximation, the earthquake source has been represented by physical parameters such as s~ismic moment, fault dimension and earthquake mag nitude. Meanwhile, destruction often results from strong ground motion due to large earthquakes at short distances. Since periods of strong ground motion are far shorter than those of seismic waves at teleseismic distances, the theory of long-period source process of earthquakes cannot be applied directly to strong ground motion at short distances. The excitation and propagation of high-frequency seismic waves are of special interest in recent earthquake seismology. In particular, the descrip tion and simulation of strong ground motion are very important not only for problems directly relevant to earthquake engineering, but also to the frac ture mechanics of earthquake faulting. Understanding of earthquake sources has been developed by investigating the complexity of faulting processes for the case of large earthquakes. Laboratory results on rock failures have also advanced the understanding of faulting mechanisms. Various attempts have been made to simulate, theoretically and empirically, the propagation of short-period seismic waves in the heterogeneous real earth.

Geocomplexity and the Physics of Earthquakes

Author: John Rundle
Publisher: American Geophysical Union
ISBN: 0875909787
Format: PDF, Kindle
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Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 120. Earthquakes in urban centers are capable of causing enormous damage. The January 16, 1995 Kobe, Japan earthquake was only a magnitude 6.9 event and yet produced an estimated $200 billion loss. Despite an active earthquake prediction program in Japan, this event was a complete surprise. Similar scenarios are possible in Los Angeles, San Francisco, Seattle, and other urban centers around the Pacific plate boundary. The development of forecast or prediction methodologies for these great damaging earthquakes has been complicated by the fact that the largest events repeat at irregular intervals of hundreds to thousands of years, resulting in a limited historical record that has frustrated phenomenological studies. The papers in this book describe an emerging alternative approach, which is based on a new understanding of earthquake physics arising from the construction and analysis of numerical simulations. With these numerical simulations, earthquake physics now can be investigated in numerical laboratories. Simulation data from numerical experiments can be used to develop theoretical understanding that can be subsequently applied to observed data. These methods have been enabled by the information technology revolution, in which fundamental advances in computing and communications are placing vast computational resources at our disposal.

Real Time Earthquake Tracking and Localisation

Author: George R. Daglish
Publisher: AuthorHouse
ISBN: 1728382335
Format: PDF, ePub, Mobi
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After the great tsunami of 2004 and the earthquake in Sichuan, China, in 2008, two big thinkers knew they must try to prevent the damage inflicted by surprise earthquakes. George R. Daglish and Iurii P. Sizov teamed up to create an experimental seismic software system that contains application areas for inclusion in an earthquake early warning software structure. In this book, they highlight the work they’ve done thus far. The algorithms can be grouped into several main types: planar earth calculations to determine epicenters; calculations over a spherical earth model to determine epicenters; rapid tabular scans to determine epicenters and hypocenters concurrently, using either spherical or spheroidal earth geometry directly; and hypocenter scans using spheroidal earth geometry. The authors also describe the testing of all members of the grouping, using real earthquake data. They assess the timing and accuracy of each against received and current results taken from the Incorporated Research Institutions for Seismology archive. If the world doesn’t take concerted action to predict and track earthquakes, the consequences will be unthinkable, which is why we must work toward real-time earthquake tracking and localization.

An Introduction to Seismology Earthquakes and Earth Structure

Author: Seth Stein
Publisher: John Wiley & Sons
ISBN: 1118687450
Format: PDF, Docs
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An Introduction to Seismology, Earthquakes and EarthStructures is an introduction to seismology and its role in theearth sciences, and is written for advanced undergraduate andbeginning graduate students. The fundamentals of seismic wave propagation are developed usinga physical approach and then applied to show how refraction,reflection, and teleseismic techniques are used to study thestructure and thus the composition and evolution of the earth. Thebook shows how seismic waves are used to study earthquakes and areintegrated with other data to investigate the plate tectonicprocesses that cause earthquakes. Figures, examples, problems, andcomputer exercises teach students about seismology in a creativeand intuitive manner. Necessary mathematical tools including vectorand tensor analysis, matrix algebra, Fourier analysis, statisticsof errors, signal processing, and data inversion are introducedwith many relevant examples. The text also addresses thefundamentals of seismometry and applications of seismology tosocietal issues. Special attention is paid to help studentsvisualize connections between different topics and view seismologyas an integrated science. An Introduction to Seismology, Earthquakes, and EarthStructure gives an excellent overview for students ofgeophysics and tectonics, and provides a strong foundation forfurther studies in seismology. Multidisciplinary examples throughout the text - catering tostudents in varied disciplines (geology, mineralogy, petrology,physics, etc.). Most up to date book on the market - includes recent seismicevents such as the 1999 Earthquakes in Turkey, Greece, andTaiwan). Chapter outlines - each chapter begins with an outline and alist of learning objectives to help students focus and study. Essential math review - an entire section reviews the essentialmath needed to understand seismology. This can be covered in classor left to students to review as needed. End of chapter problem sets - homework problems that cover thematerial presented in the chapter. Solutions to all odd numberedproblem sets are listed in the back so that students can tracktheir progress. Extensive References - classic references and more currentreferences are listed at the end of each chapter. A set of instructor's resources containing downloadable versionsof all the figures in the book, errata and answers to homeworkproblems is available at:http://levee.wustl.edu/seismology/book/. Also available on thiswebsite are PowerPoint lecture slides corresponding to the first 5chapters of the book.

Fault Zone Properties and Earthquake Rupture Dynamics

Author: Eiichi Fukuyama
Publisher: Academic Press
ISBN: 9780080922461
Format: PDF, Mobi
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The dynamics of the earthquake rupture process are closely related to fault zone properties which the authors have intensively investigated by various observations in the field as well as by laboratory experiments. These include geological investigation of the active and fossil faults, physical and chemical features obtained by the laboratory experiments, as well as the seismological estimation from seismic waveforms. Earthquake dynamic rupture can now be modeled using numerical simulations on the basis of field and laboratory observations, which should be very useful for understanding earthquake rupture dynamics. Features: * First overview of new and improved techniques in the study of earthquake faulting * Broad coverage * Full color Benefits: * A must-have for all geophysicists who work on earthquake dynamics * Single resource for all aspects of earthquake dynamics (from lab measurements to seismological observations to numerical modelling) * Bridges the disciplines of seismology, structural geology and rock mechanics * Helps readers to understand and interpret graphs and maps Also has potential use as a supplementary resource for upper division and graduate geophysics courses.