Near Source Contributions to Teleseismic P Wave Coda and Regional Phases PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Near Source Contributions to Teleseismic P Wave Coda and Regional Phases PDF full book. Access full book title Near Source Contributions to Teleseismic P Wave Coda and Regional Phases by . Download full books in PDF and EPUB format.
Author: Publisher: ISBN: Category : Languages : en Pages : 140
Book Description
This report presents the results of an investigation of near-source effects on teleseismic P-wave and early P-wave coda spectra for underground explosions. The underlying objective of this research has been to determine whether the differential behavior of P and P coda can be exploited to remotely determine near-source properties such as overburden velocity, burial depth, and degree of saturation. The report also contains a review paper on the pP phase, focussed on assessing the various methodologies that have been used to determine pP parameters and trying to reconcile the existing discrepancies in various estimates. The final section of the report is an encyclopedia article on the role of seismological monitoring of nuclear testing treaties. Energy radiated upward from underground nuclear explosions has a complex interaction with the free surface that strongly influences the seismic wavefields recorded at teleseismic and regional distances. This interaction, differing from that for earthquakes primarily due to the much higher strains and strain rates involved, is essential to understand for both explosion yield estimation and event discrimination. Reflection of explosion P wave energy from the free surface, which produces the pP phase, involves frequency-dependent, non-linear processes that are intimately linked to surface spallation.
Author: Publisher: ISBN: Category : Languages : en Pages : 140
Book Description
This report presents the results of an investigation of near-source effects on teleseismic P-wave and early P-wave coda spectra for underground explosions. The underlying objective of this research has been to determine whether the differential behavior of P and P coda can be exploited to remotely determine near-source properties such as overburden velocity, burial depth, and degree of saturation. The report also contains a review paper on the pP phase, focussed on assessing the various methodologies that have been used to determine pP parameters and trying to reconcile the existing discrepancies in various estimates. The final section of the report is an encyclopedia article on the role of seismological monitoring of nuclear testing treaties. Energy radiated upward from underground nuclear explosions has a complex interaction with the free surface that strongly influences the seismic wavefields recorded at teleseismic and regional distances. This interaction, differing from that for earthquakes primarily due to the much higher strains and strain rates involved, is essential to understand for both explosion yield estimation and event discrimination. Reflection of explosion P wave energy from the free surface, which produces the pP phase, involves frequency-dependent, non-linear processes that are intimately linked to surface spallation.
Author: Brian L. N. Kennett Publisher: Cambridge University Press ISBN: 1108830749 Category : Business & Economics Languages : en Pages : 505
Book Description
Developments in seismology including correlation techniques, heterogeneity and waveform inversion, illustrated with observational examples.
Author: Barbara Romanowicz Publisher: Elsevier ISBN: 0444535756 Category : Science Languages : en Pages : 873
Book Description
Treatise on Geophysics: Seismology and Structure of the Earth, Volume 1, provides a comprehensive review of the state of knowledge on the Earths structure and earthquakes. It addresses various aspects of structural seismology and its applications to other fields of Earth sciences. The book is organized into four parts. The first part principally covers theoretical developments and seismic data analysis techniques from the end of the nineteenth century until the present, with the main emphasis on the development of instrumentation and its deployment. The second part reviews the status of knowledge on the structure of the Earths shallow layers, starting with a global review of the Earth's crustal structure. The third part focuses on the Earth's deep structure, divided into its main units: the upper mantle, the transition zone and upper-mantle discontinuities, the D region at the base of the mantle, and the Earth's core. The fourth part comprises two chapters which discuss constraints on Earth structure from fields other than seismology: mineral physics and geodynamics. Self-contained volume starts with an overview of the subject then explores each topic with in depth detail Extensive reference lists and cross references with other volumes to facilitate further research Full-color figures and tables support the text and aid in understanding Content suited for both the expert and non-expert
Author: Haruo Sato Publisher: Academic Press ISBN: 0080880339 Category : Science Languages : en Pages : 497
Book Description
Seismic waves generated by earthquakes have been interpreted to provide us information about the Earth’s structure across a variety of scales. For short periods of less than 1 second, the envelope of seismograms changes significantly with increased travel distance and coda waves are excited by scattering due to randomly distributed heterogeneities in the Earth. Deterministic structures such as horizontally uniform velocity layer models in traditional seismology cannot explain these phenomena. This book focuses on the Earth heterogeneity and scattering effects on seismic waves. Topics covered are recent developments in wave theory and observation including: coda wave analysis for mapping medium heterogeneity and monitoring temporal variation of physical properties, radiation of short-period seismic waves from an earthquake fault, weak localization of seismic waves, attenuation of seismic waves in randomly porous media, synthesis of seismic wave envelopes in short periods, and laboratory investigations of ultrasonic wave propagation in rock samples. Understanding new methods for the analysis of short-period seismic waves to characterize the random heterogeneity of the Earth on many scales Observations of seismic wave scattering Discussion of techniques for mapping medium heterogeneity and for monitoring temporal change in medium characteristics Up-to-date techniques for the synthesis of wave envelopes in random media
Author: Megan S. Avants Publisher: ISBN: 9781303842283 Category : Languages : en Pages : 142
Book Description
Near-source path effects imprint the wave field emanating from a seismic source and, if not well resolved, can obscure the details of source characteristics determined from observations of the seismic waves at regional and teleseismic distances (& ge;200 km). These effects are particularly strong for crustal sources such as shallow earthquakes and underground nuclear explosions. First, I explore 2D effects of random seismic P-wave velocity heterogeneity resulting from volumetric heterogeneity in the upper mantle and variability of the Moho on the amplitude decay of the regional phase Pn. Results indicate that the pattern of amplitude decay due to geometric spreading for a simple Earth model is more complex than that for an Earth model containing strong heterogeneity in the mantle lid. Next, I implement the representation theorem in a method which collects displacement and strain components output from a 3D finite difference program capable of including realistic surface topography and geologic structure in a 3D velocity model, and calculates teleseismic 3D Green functions (3DGFs) to specified receiver locations. Green functions produced from a 3D source model match Green functions produced from a 1D source model for theoretical source-receiver geometries. This new method is then applied to the problem of constraining the source depth and location of the three nuclear tests conducted by North Korea, by using a realistic topography model for the mountainous test region to calculate 3DGFs for several possible locations of each event. Amplitude ratios of P and pP from 3DGFs are correlated to those in observed stacked traces. Results show a sensitivity of this method to source depth and location across the test site region with source depths slightly greater than published estimates, but relative locations consistent with other studies. Finally, I determine a rupture model of the 2008 Wenchuan earthquake using 3DGFs calculated in a velocity model containing the dramatic topographic contrast in the fault area, and compare results with a rupture model produced using 1DGFs. Rupture models derived from 1D and 3D synthetic source regions are very similar to each other, and both are consistent with other studies.
Author: 
Author: 
Author: Brian L. N. Kennett
Author: United States. Arms Control and Disarmament Agency
Author: 
Author: United States. Arms Control and Disarmament Agency
Author: Michael Andrew Huvud Hedlin
Author: United States. Arms Control and Disarmament Agency
Author: Barbara Romanowicz
Author: Haruo Sato
Author: Megan S. Avants