Download or read book Inversion of Regional Surface wave Spectra for Source Parameters of California Earthquakes written by Susan L. Beck and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Source Parameters and Propagation path Effects for Earthquakes in the Baja California Norte and Imperial Valley Regions written by Raul Ramon Castro and published by . This book was released on 1983 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Full 3d Waveform Inversions and Their Applications in Southern California written by En-Jui Lee and published by . This book was released on 2013 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground motion recordings have been used widely in analyzing physical properties of the Earth materials and mechanism of earthquakes. The recent advances in computational technology and numerical methods allow seismologists to accurately simulate wave propagation in 3D strongly heterogeneous media and opened up the possibility of extracting more information from waveform recordings for seismic tomography and earthquake source inversion. Furthermore, body wave and surface wave phases can be all used to benefit seismic imaging and source inversion without additional assumptions in the full-wave method. To examine the advantages of full-wave method, we have implemented our tomogaphic and earthquake source inversion algorithms in Southern California where has complex geological structures and has well distributed seismic broadband arrays. We have developed a semi-automated waveform segmentation and selection algorithm and the tool has been applied to large amounts of waveforms for our full-wave earthquake source and tomographic inversions. In our earthquake source inversion algorithm, the receiver Green's tensors, which comprise the spatial-temporal displacements produced by the three orthogonal unit impulsive point forces acting at the receiver, are computed in our updated 3D velocity model. The receiver Green's tensors are stored in disk for efficiently generating synthetic seismograms by using reciprocity between stations and any spatial grid point in our model, and therefore our source inversion algorithm could rapidly invert earthquake source parameters and could provide physics-based ground motion predictions. In our tomographic inversion, the velocity model has been iteratively improved by using the scattering-integral and adjoin-wavefield methods. To accelerate iterations, the LSQR algorithm has been paralleled and optimized for solving our large tomographic inversion systems. The optimized LSQR algorithm reduces both communication cost and memory usage during inversions, so the calculation time and required computational resources are significantly reduced. After 26 iterations, the new crustal velocity model reveals a strongly heterogeneous crustal structure in Southern California. In addition, our tomography also reveals many features that are not shown in the initial model, but have been found in other independent studies. The new tomography enables more accurate physics-based seismic hazard applications and the tectonic reconstruction of Southern California.

Download or read book Monitoring the Comprehensive Nuclear Test Ban Treaty Source Processes and Explosion Yield Estimation written by Goran Ekstrom and published by Springer Science & Business Media. This book was released on 2001-12-01 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pure appl. geophys., by 161 nations. Entry of the treaty into force, however, is still uncertain since it requires ratification by all 44 nations that have some nuclear capability and, as of 15 June 2001, only 31 of those nations have done so. Although entry of the CTBT into force is still uncertain, seismologists and scientists in related fields, such as radionuclides, have proceeded with new research on issues relevant to monitoring compliance with it. Results of much of that research may be used by the International Monitoring System, headquartered in Vienna, and by several national centers and individual institutions, to monitor compliance with the CTBT. New issues associated with CTBT monitoring in the 21st century have presented scientists with many new challenges. They must be able to effectively monitor com pliance by several countries that have not previously been nuclear powers. Effective monitoring requires that we be able to detect and locate much smaller nuclear events than ever before and to distinguish them from small earthquakes and other types of explosions. We must have those capabilities in regions that are seismically active and geologically complex, and where seismic waves might not propagate efficiently.

Download or read book Analysis of Earthquake Rupture Processes and Mantle Structure Using Regional Seismic Networks written by Jeroen Egbert Ritsema and published by . This book was released on 1995 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Cause of the Body wave Surface wave Discriminant Between Earthquakes and Underground Nuclear Explosions at Near regional Distances written by William Alan Peppin and published by . This book was released on 1974 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Frequency 3 Component Waveform Inversion for Source and Structural Parameters written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the results of three studies to develop and verify techniques to classify weak seismic events. (1) The method and results of full waveform inversion for both detailed source parameters and structure parameters are described. Input data were seismograms from industrial explosions in Eastern Kazakhstan recorded by the NRDC seismic network in 1987. Very good fits were produced between the synthetic seismograms and the observed data on all three components simultaneously and for P-wave, Rayleigh wave, and Love wave. We interpreted some of the inverted source parameters as characteristic of several different types of industrial surface mining operations. (2) The same technique was used to determine detailed source and structure parameters using an event that is highly relevant to nuclear monitoring. We determined that a salt mine collapse near Solikamsk, the Ural Mountains on 5 January 1995 was most likely a mine collapse instead of an underground explosions. (3) This study was carried out jointly by the Seismology Group of the University of Colorado and the Russian team from the Int'l Institute of Earthquake Prediction Theory and Math. Geophysics. We developed a new technique to identify a seismic event based on simultaneous inversion of surface wave amplitude spectra and signs of first motions of body wave. We applied this technique to several events near the Chinese test site at Lop Nor and demonstrated significant differences in source parameters characterizing explosions and natural earthquakes in this region.

Download or read book Abstract Journal in Earthquake Engineering written by and published by . This book was released on 1995 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1058 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Earthquake Spectra from Long Valley California Using the NEWT Seismic System written by Stephen R. McNutt and published by . This book was released on 1989 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Geophysical exploration of the solar system written by Cedric Schmelzbach and published by Academic Press. This book was released on 2021-08-31 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Formation and Structure of Planets, Volume 62 in the Advances in Geophysics series, highlights new chapters on a variety of topics in the field, including The evolution of multi-method imaging of structures and processes in environmental geophysics, An introduction to variational inference in Geophysical inverse problems, Moment tensor inversion, and more. Provides high-level reviews of the latest innovations in geophysics Written by recognized experts in the field Presents an essential publication for researchers in all fields of geophysics

Download or read book Earthquakes and Multi hazards Around the Pacific Rim Vol I written by Yongxian Zhang and published by Birkhäuser. This book was released on 2017-12-20 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first of two volumes devoted to earthquakes and multi-hazards around the Pacific Rim. The circum-Pacific seismic belt is home to roughly 80% of the world’s largest earthquakes, making it the ideal location for investigating earthquakes and related hazards such as tsunamis and landslides. Gathering 16 papers that cover a range of topics related to multi-hazards, the book is divided into three sections: earthquake physics, earthquake simulation and data assimilation, and multi-hazard assessment and earthquake forecasting models. The first section includes papers on laboratory-derived rheological parameters as well as seismic studies in the Gulf of California and China. In turn, the second section includes papers on improvements in earthquake simulators as well as the statistical methods used to evaluate their performance, automated methods for determining fault slip using near-field interferometric data, variabilities in earthquake stress drops in California, and the use of social media data to supplement physical sensor data when estimating local earthquake intensity. The final section includes a paper on probabilistic tsunami hazard assessment, several papers on time-dependent seismic hazard analysis around the Pacific Rim, and a paper on induced and triggered seismicity at the Geysers geothermal field in California. Rapid advances are being made in our understanding of multi-hazards, as well as the range of tools used to investigate them. This volume provides a representative cross-section of how state-of-the-art knowledge and tools are currently being applied to multi-hazards around the Pacific Rim. The material here should be of interest to scientists involved in all areas of multi-hazards, particularly seismic and tsunami hazards. In addition, it offers a valuable resource for students in the geosciences, covering a broad spectrum of topics related to hazard research.

Download or read book Seismological Investigations and Tectonic Interpretation of the April 1992 Cape Mendocino Earthquake Sequence written by Susan Y. Schwartz and published by . This book was released on 1996 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Part I 3D Simulations of Short period Surface wave Propagation in Southern California written by Jiang Qu and published by . This book was released on 1996 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Source Parameters of Southern California Earthquakes written by Wayne Thatcher and published by . This book was released on 1973 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Spectrum Analysis and Array Processing written by Simon S. Haykin and published by . This book was released on 1991 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book National Clearinghouse for Loma Prieta Earthquake Information Catalog written by and published by . This book was released on 1992-04 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: