| Development of Regional Phase Tomographic Attenuation Models for Eurasia |
Sep 2008 |
11 pages |
| Authors:
Thorne Lay; Xiao-Bi Xie; Xiaoning D Yang; CALIFORNIA UNIV SANTA CRUZ
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 | We are developing regional-phase (Pn, Pg, Sn, Lg) tomographic attenuation models for Eurasia. The models will be integrated into the National Nuclear Security Administration (NNSA) Knowledge Base and used in the Magnitude and Distance Amplitude Correction (MDAC) station calibration for the development of regional seismic discriminants. Our current focus is on Pn, an extremely important phase in seismic event identification. Accurately accounting for regional-phase geometric spreading is critical for the ... |
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| Near Source Energy Partitioning for Regional Waves in 2D and 3D Models |
30-Apr-2008 |
62 pages |
| Authors:
Xiao-Bi Xie; Thome Lay; Ru-Shan Wu; CALIFORNIA UNIV SANTA CRUZ
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| The complex excitation and energy partitioning mechanisms yielding regional phases are difficult to empirically separate by data analysis. Thus, numerical modeling approaches are valuable for investigating excitation and propagation of regional seismic phases. We use accurate full-wave simulations (2D and 3D finite-difference method, and 2D boundary element method) to calculate seismic wave excitation and propagation in near-source region. An embedded array slowness analysis is used for quantifying how energy will ... |
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| Development of Regional Phase Tomographic Attenuation Models for Eurasia |
Sep 2007 |
12 pages |
| Authors:
Thorne Lay; Xiao-Bi Xie; Xiaoning Yang; Marie D Arrowsmith; CALIFORNIA UNIV SANTA CRUZ
|
| We are developing regional-phase (Pn, Pg, Sn, Lg) tomographic attenuation models for Eurasia. The models will be integrated into the National Nuclear Security Administration (NNSA) Knowledge Base and used in the Magnitude and Distance Amplitude Correction (MDAC) station calibration for the development of regional seismic discriminants. Our current focus is on Pn, an extremely important phase in seismic event identification. Accurately accounting for regional-phase geometric spreading is critical for the ... |
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| Synthesizing High-Frequency (1-25 HZ) Regional Phases at Large Distances (>1000 KM) Using Generalized Screen Propagators (GSP) |
SEP 2004 |
53 pages |
| Authors:
Ru-Shan Wu; Xiao-Bi Xie; Xianyun Wu; CALIFORNIA UNIV SANTA CRUZ CA INSTITUTE OF GEOPHYSICS AND PLANETARY PHYSICS
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| Based on the half-space screen propagator developed in our previous project, we successfully extended the method to the case of irregular surface topography by the conformal and non-conformal topographic transforms. Its validity and potential applications have been numerically demonstrated by comparing with the boundary element method. The new method can handle combined effects of small-scale heterogeneities (random media) and rough random topography on Lg wave propagation. It is also 2-3 ... |
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| Lg Wave Propagation using SH and P and SV Screen Propagators in Heterogeneous Crusts With Irregular Topography |
Sep 2000 |
11 pages |
| Authors:
Ru-Shan Wu; Xiao-Bi Xie; Xian-Yun Wu; CALIFORNIA UNIV SANTA CRUZ
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| This study is aimed at development and application of new wave propagation and modeling methods for regional waves in heterogeneous crustal waveguides using one-way wave approximation. The half-space generalized screen propagators (GSP) for both SH and P-SV waves have taken the free surface into the formulation and adopt a fast dual domain implementation. The method is several orders of magnitude faster than finite-difference method with a similar accuracy for certain ... |
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| Study of Ocean Bottom Interactions With Acoustic Waves by a New Elastic Wave Propagation Algorithm and an Energy Flow Analysis Technique |
30 Sep 1998 |
4 pages |
| Authors:
Ru-Shan Wu; Xiao-Bi Xie; CALIFORNIA UNIV SANTA CRUZ
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| The long-term goal is to develop a new method and the code to simulate 3D acoustic/elastic wave propagation and interaction with the ocean water and ocean bottom environment. The method will be applied to numerical simulations and imaging to study the wave/sea-bottom interaction, energy partitioning, scattering mechanism and other problems that are crucial for many ocean bottom-surveying techniques. Our understanding on shallow water acoustic wave propagation and its interaction with ... |
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| Synthetic Seismograms in Heterogeneous Media and Study of Formation and Propagation of Regional Phases, |
14 AUG 1995 |
8 pages |
| Authors:
Ru-Shan Wu; Thorne Lay; Xiao-Bi Xie; Lian-Jie Huang; CALIFORNIA UNIV SANTA CRUZ
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| The object of this project is aimed at development and application of a new 3D wave propagation and modeling method in complex heterogeneous media using one-way wave approximation to study many outstanding problems of regional wave propagation in the context of nuclear test monitoring. The great advantages of one-way propagation methods are the fast speed of computation, often by several orders of magnitudes faster than finite difference and finite element ... |
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