Download or read book Kinematic Earthquake Source Imaging written by Wenyuan Fan and published by . This book was released on 2017 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earthquakes are the primary source of seismic waves in seismology and understanding the earthquake source is essential for predicting ground motions and detailing the physics of rupture. Earthquake kinematic source imaging describes the whole rupture process during an earthquake. It does not directly require the resolved source model to be physically or dynamically plausible, but can help in understanding the conditions of rupture dynamics. Therefore, accurate earthquake source models are highly desirable. In Chapter 2, we develop a frequency-based approach to earthquake slip inversion that requires no prior information on the rupture velocity or slip-rate functions. In Chapter 3, we characterize the rupture process of the 25 April 2015 Nepal earthquake with globally recorded teleseismic P waves. In Chapter 4, we investigate the 10 January 2012 Mw 7.2 Sumatra earthquake in the Wharton basin and detect dynamically-triggered large early aftershocks occurring on or near the subduction interface. In Chapter 5, we constrain the spatiotemporal evolution of the 2009 Tonga-Samoa earthquake with global P-wave back-projection and a multiple moment-tensor inversion. Our results show that the rupture branches east of the trench axis were controlled by the geometry of bending-related faults on the Pacific plate, and that the rupture branch west of the trench axis may correlate with along-strike fore-arc segmentation. In Chapter 6, we detect and locate 48 previously unidentified large early aftershocks triggered by 7

Download or read book Theories and Applications of Enhanced Earthquake Back projection Imaging written by Ailin Zhang and published by . This book was released on 2019 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earthquake source imaging is an efficient tool to reveal the kinematic rupture process of earthquakes. The accuracy and robustness of source imaging is of vital importance to con- strain source properties and help discriminate among potential physical mechanisms. In this work, I develop array-based approach: enhanced back-projection and coherence method to provide better constraints on kinematic source imaging. Slowness correction is proposed to improve the source imaging of complicated rupture in conjugate fault systems. The correction is capable of mitigating 3D structural effects that commonly exist for M8 earthquakes. For deep earthquakes, I introduce 3D back-projection which provides depth resolution of the rupture front. Resolving ruptures in 3D space helps us to understand the rupture process and physical mechanisms of deep earthquakes. Furthermore, coherence model is established to relate earthquake source size with inter-station cross-correlation. This method creates independent measures to validate and constrain the source sizes of deep earthquakes. Aforementioned array-based approaches have been successfully applied to recently oc- curred earthquakes, and I will take this chance to revisit the rupture mechanisms of the events revealed by enhanced source imaging

Download or read book A Robust Method to Estimate Kinematic Earthquake Source Parameters written by Sebastian Heimann and published by . This book was released on 2011 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book AutoBATS and 3D MUSIC New Approaches to Imaging Earthquake Rupture Behaviors written by Pei-Ru Jian and published by Springer Nature. This book was released on 2021-09-27 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the kinematic earthquake rupture studies from moment tenor to spatial-temporal rupture imaging. For real-time seismic hazard monitoring, the new stable automatic moment tensor (AutoBATS) algorithm is developed and implemented for the real-time MT reports by the Taiwan Earthquake Science Information System (TESIS). In order to understand the rupture behavior of the 2013 Mw 8.3 Okhotsk deep earthquake sequence, the 3D MUltiple SIgnal Classification Back Projection (MUSIC BP) with P and pP phases is applied. The combined P- and pP-wave BP imaging of the mainshock shows two stages of anti-parallel ruptures along two depths separating for about 10~15 km. Unusual super-shear ruptures are observed through the 3D BP images of two Mw 6.7 aftershocks. In last two chapters, the 3D BP imaging reveals similar rupture properties of two shallow catastrophic earthquakes (Mw=6.4) in southwestern Taiwan. Both the 2010 Jiashian and 2016 Meinong earthquakes ruptured westward with similar velocity of ~2.5 km/s along a NE-ward shallow dipping blind fault. The rupture similarities of the doublet suggest two parallel elongate asperities along the causative fault. After several decades of seismic quiescence, the 2010 Jiashian event initiated the rupture at the deeper asperity and triggered the shallower asperity which caused catastrophes six years later.

Download or read book Imaging the Rupture Processes of Earthquakes Using the Relative Back Projection Method written by Hao Zhang and published by Springer. This book was released on 2017-12-27 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis adopts the relative back-projection method to dramatically reduce “swimming” artifacts by identifying the rupture fronts in the time window of a reference station; this led to a faster and more accurate image of the rupture processes of earthquakes. Mitigating the damage caused by earthquakes is one of the primary goals of seismology, and includes saving more people’s lives by devising seismological approaches to rapidly analyze an earthquake’s rupture process. The back-projection method described in this thesis can make that a reality.

Download or read book Kinematic and Dynamic Modeling of the Earthquake Source written by Jan Schmedes and published by . This book was released on 2010 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Simulations we address two important questions. First, we use kinematic models to investigate the probable cause for the observation that the peak ground motion saturates at distances close to the fault. Second, we use dynamic models to explore how the transition to supershear propagation speed and the ground motion are affected by the autocorrelation of the initial stress. We find that the stress in the Earth is highly heterogeneous with a slight correlation.

Download or read book Imaging Modeling and Assimilation in Seismology written by Yong-Gang Li and published by Walter de Gruyter. This book was released on 2012-02-22 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents current approaches in geophysical research of earthquakes. A global authorship from top institutions presents case studies to model, measure, and monitor earthquakes. Among others a full-3D waveform tomography method is introduced, as well as propagator methods for modeling and imaging. In particular the earthquake prediction method makes this book a must-read for researchers in the field.

Download or read book Source Mechanisms of Earthquakes written by Agustín Udías Vallina and published by Cambridge University Press. This book was released on 2014-04-24 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: An innovative new approach to studying earthquake source mechanisms, combining theory and observation, for graduate students, researchers and seismology professionals.

Download or read book Reconstruction of the Earthquake Rupture Process Through Coherent Teleseismic Imaging and Statistical Modeling written by Marina Corradini and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many studies have attempted to illuminate rupture complexities of large earthquakes through the use of coherent imaging techniques such as back-projection (BP). Recently, Fukahata et al. (2013) suggested that, from a theoretical point of view, the BP image of the rupture is related to the slip motion on the fault. However, the quantitative relationship between the BP images and the physical properties of the earthquake rupture process still remains unclear.Our work aims at clarifying how BP images of the radiated wavefield can be used to infer spatial heterogeneities in slip and rupture velocity along the fault. We simulate different rupture processes using a line source model. For each rupture model, we calculate synthetic seismograms at three teleseismic arrays and we apply the BP technique to identify the sources of high-frequency (HF) radiation. This procedure allows for the comparison of the BP images with the originating rupture model, and thus the interpretation of HF emissions in terms of along-fault variation of the three kinematic parameters: rise time, final slip, rupture velocity. Our results show that the HF peaks retrieved from BP analysis are most closely associated with space-time heterogeneities of slip acceleration. We verify our findings on two major earthquakes that occurred 9 years apart on the strike-slip Swan Islands fault: the Mw 7.3 2009 and the Mw 7.5 2018 North of Hondurasearthquakes. Both events followed a simple linear geometry, making them suitable for comparison with our synthetic approach. Despite the simple geometry, both slip-rate functions are complex, with several subevents. Our preliminary results show that the BP image of HF emissions allows to estimate a rupture length and velocity which are compatible with other studies and that strong HF radiation corresponds to the areas of large variability of the moment-rate function. An outstanding question is whether one can use the BP image of the earthquake to retrieve the kinematic parameters along the fault. We build on the findings obtained in the synthetic examples by training a neural network model to directly predict the kinematic parameters along the fault, given an input BP image. We train the network on a large number of different synthetic rupture processes and their BP images, with the goal of identifying the statistical link between HF radiation and rupture kinematic parameters. Our results show that the neural network applied to the BP image of the earthquake is able to predict the values of rise time and rupture velocity along the fault, as well as thecentral position of the heterogeneity, but not the absolute slip values, to which the HF BP approach is relatively insensitive. Our work sheds some light on the gap currently existing between the theoretical description of the generation of HF radiation and the observations of HF emissions obtained by coherent imaging techniques, tackling possible courses of action and suggesting new perspectives.

Download or read book Advances in Seismic Event Location written by Cliffort H. Thurber and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Seismic Event Location provides a broad overview of the fundamental issues involved in seismic event location, and presents a variety of state-of-the-art location methods and applications at a wide range of spatial scales. Three important themes in the book are: seismic monitoring for a Comprehensive Nuclear-Test-Ban Treaty (CTBT), seismic event location in three-dimensional Earth models, and methods for multiple-event location. Each chapter contains background material to help readers less familiar with the topics covered, as well as to provide abundant references for readers interested in probing deeper into a topic. However, most of the emphasis is on recent advances in methodology and their application. Audience: The book is intended primarily for academic and professional researchers and graduate students in seismology.

Download or read book Finite difference Synthetic Seismograms for Kinematic Models of the Earthquake Source written by and published by . This book was released on 1979 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinematic Earthquake Sources of High and Low Frequencies and Their Relation to Earth Structure written by Tomoko Elizabeth Yano and published by . This book was released on 2012 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on results from a synthetic test, we demonstrate that the new back-propagation method is better than existing back-projection method because it not only can locate the spatial-temporal locations of the target sources but also can fairly well recover their amplitudes.

Download or read book Earthquake Source Mechanics written by Shamita Das and published by American Geophysical Union. This book was released on 1986 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seismic True amplitude Imaging written by Jörg Schleicher and published by SEG Books. This book was released on 2007 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a pictorial presentation of the basic principles of Kirchhoff-type imaging and proceeding to a comprehensive treatment of its kinematic and dynamic aspects, this book is a valuable addition for anyone interested in the theory and practices of seismic data processing for imaging and parameter estimation with all its attendant processes.

Download or read book Kinematic Wavefield Attributes in Seismic Imaging written by Kai-Uwe Vieth and published by . This book was released on 2001 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Earthquake Source Physics on Various Scales written by Adrien Oth and published by Birkhäuser. This book was released on 2014-11-24 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earthquake rupture is a process of remarkable complexity. Over the past few decades, scientists have become aware of its high variability on all scales as well as its wide dynamic range. At the same time, a thorough understanding of the seismic source process is a key element of reliable earthquake ground motion prediction. The present book contains a comprehensive collection of contributions originating from the 2012 ECGS Workshop Earthquake Source Physics on Various Scales, held in Luxembourg. The seventeen articles in this volume cover theoretical and observational aspects of the earthquake source process, ranging from tiny, laboratory-generated M -6 events to the source complexity and radiated energy of the world’s greatest earthquakes. Among other aspects, the papers provide new insights into the relationship of earthquake recurrence time with fault frictional parameters, how the results of lab-based friction experiments relate to observational source studies, and how geometrical source complexity can be quantified. In particular, several papers are devoted to the question whether small and large earthquakes scale self-similarly or if they show differences in their dynamic source characteristics, which is one of the most hotly debated aspects of modern seismology. The volume provides an integrated view of the current state-of-the-art knowledge on the earthquake source process on all scales and will be useful to students and professional researchers who are interested in these phenomena.

Download or read book Isotropic and Anisotropic Seismic Tomography Using Active Source and Earthquake Records written by Yu-Pin Lin and published by Springer. This book was released on 2017-06-16 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents investigations on the Earth's seismic structure using both active-source and natural earthquake records. It discusses the ground-truth data obtained from the TAiwan Integrated GEodynamics Research (TAIGER) active-source experiments that provides excellent and unique insights into the shallow crustal structures beneath Taiwan. It also explores the full-wave sensitivity kernels, which account for the effects of all possible wave interferences involved in shear-wave splitting and therefore loosen the restrictions on source-receiver geometry amenable to shear-wave splitting analysis. Moreover, it describes the 3D Fréchet kernels, which enable us to resolve the vertical and lateral variations in seismic anisotropy and obtain 3D images of the Earth's anisotropic structure, as well as the practice in Southern California that enables us to infer the state of the stress and strain in the lithosphere and the dynamics of the asthenospheric mantle flow for a better understanding of the strength and deformation in the upper mantle beneath the San Andreas Fault system.