The Prospect of using ThreeDimensional Earth Models To Improve Nuclear Explosion Monitoring and Ground Motion Hazard Assessment
Abstract
The last ten years have brought rapid growth in the development and use of threedimensional (3D) seismic models of Earth structure at crustal, regional and global scales. In order to explore the potential for 3D seismic models to contribute to important societal applications, Lawrence Livermore National Laboratory (LLNL) hosted a 'Workshop on MultiResolution 3D Earth Models to Predict Key Observables in Seismic Monitoring and Related Fields' on June 6 and 7, 2007 in Berkeley, California. The workshop brought together academic, government and industry leaders in the research programs developing 3D seismic models and methods for the nuclear explosion monitoring and seismic ground motion hazard communities. The workshop was designed to assess the current state of work in 3D seismology and to discuss a path forward for determining if and how 3D Earth models and techniques can be used to achieve measurable increases in our capabilities for monitoring underground nuclear explosions and characterizing seismic ground motion hazards. This paper highlights some of the presentations, issues, and discussions at the workshop and proposes two specific paths by which to begin quantifying the potential contribution of progressively refined 3D seismic models in critical applied arenas. Seismic monitoring agencies are tasked with detection, location,more »
 Authors:
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 950637
 Report Number(s):
 LLNLJRNL408914
TRN: US200910%%282
 DOE Contract Number:
 W7405ENG48
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Seismological Research Letters, vol. 80, N/A, January 30, 2009, pp. 3139; Journal Volume: 80
 Country of Publication:
 United States
 Language:
 English
 Subject:
 58 GEOSCIENCES; ACCURACY; ALGORITHMS; DETECTION; EXPLOSIONS; FINITE DIFFERENCE METHOD; GROUND MOTION; KERNELS; MONITORING; NUCLEAR EXPLOSIONS; PHYSICS; RESEARCH PROGRAMS; S WAVES; SEISMIC WAVES; SEISMOLOGY; SENSITIVITY; TOMOGRAPHY; WAVE FORMS; WAVE PROPAGATION
Citation Formats
Zucca, J J, Walter, W R, Rodgers, A J, Richards, P, Pasyanos, M E, Myers, S C, Lay, T, Harris, D, and Antoun, T. The Prospect of using ThreeDimensional Earth Models To Improve Nuclear Explosion Monitoring and Ground Motion Hazard Assessment. United States: N. p., 2008.
Web.
Zucca, J J, Walter, W R, Rodgers, A J, Richards, P, Pasyanos, M E, Myers, S C, Lay, T, Harris, D, & Antoun, T. The Prospect of using ThreeDimensional Earth Models To Improve Nuclear Explosion Monitoring and Ground Motion Hazard Assessment. United States.
Zucca, J J, Walter, W R, Rodgers, A J, Richards, P, Pasyanos, M E, Myers, S C, Lay, T, Harris, D, and Antoun, T. 2008.
"The Prospect of using ThreeDimensional Earth Models To Improve Nuclear Explosion Monitoring and Ground Motion Hazard Assessment". United States.
doi:. https://www.osti.gov/servlets/purl/950637.
@article{osti_950637,
title = {The Prospect of using ThreeDimensional Earth Models To Improve Nuclear Explosion Monitoring and Ground Motion Hazard Assessment},
author = {Zucca, J J and Walter, W R and Rodgers, A J and Richards, P and Pasyanos, M E and Myers, S C and Lay, T and Harris, D and Antoun, T},
abstractNote = {The last ten years have brought rapid growth in the development and use of threedimensional (3D) seismic models of Earth structure at crustal, regional and global scales. In order to explore the potential for 3D seismic models to contribute to important societal applications, Lawrence Livermore National Laboratory (LLNL) hosted a 'Workshop on MultiResolution 3D Earth Models to Predict Key Observables in Seismic Monitoring and Related Fields' on June 6 and 7, 2007 in Berkeley, California. The workshop brought together academic, government and industry leaders in the research programs developing 3D seismic models and methods for the nuclear explosion monitoring and seismic ground motion hazard communities. The workshop was designed to assess the current state of work in 3D seismology and to discuss a path forward for determining if and how 3D Earth models and techniques can be used to achieve measurable increases in our capabilities for monitoring underground nuclear explosions and characterizing seismic ground motion hazards. This paper highlights some of the presentations, issues, and discussions at the workshop and proposes two specific paths by which to begin quantifying the potential contribution of progressively refined 3D seismic models in critical applied arenas. Seismic monitoring agencies are tasked with detection, location, and characterization of seismic activity in near real time. In the case of nuclear explosion monitoring or seismic hazard, decisions to further investigate a suspect event or to launch disaster relief efforts may rely heavily on realtime analysis and results. Because these are weighty decisions, monitoring agencies are regularly called upon to meticulously document and justify every aspect of their monitoring system. In order to meet this level of scrutiny and maintain operational robustness requirements, only mature technologies are considered for operational monitoring systems, and operational technology necessarily lags contemporary research. Current monitoring practice is to use relatively simple Earth models that generally afford analytical prediction of seismic observables (see Examples of Current Monitoring Practice below). Empirical relationships or corrections to predictions are often used to account for unmodeled phenomena, such as the generation of Swaves from explosions or the effect of 3dimensional Earth structure on wave propagation. This approach produces fast and accurate predictions in areas where empirical observations are available. However, accuracy may diminish away from empirical data. Further, much of the physics is wrapped into an empirical relationship or correction, which limits the ability to fully understand the physical processes underlying the seismic observation. Every generation of seismology researchers works toward quantitative results, with leaders who are active at or near the forefront of what has been computationally possible. While recognizing that only a 3dimensional model can capture the full physics of seismic wave generation and propagation in the Earth, computational seismology has, until recently, been limited to simplifying model parameterizations (e.g. 1D Earth models) that lead to efficient algorithms. What is different today is the fact that the largest and fastest machines are at last capable of evaluating the effects of generalized 3D Earth structure, at levels of detail that improve significantly over past efforts, with potentially wide application. Advances in numerical methods to compute travel times and complete seismograms for 3D models are enabling new ways to interpret available data. This includes algorithms such as the Fast Marching Method (Rawlison and Sambridge, 2004) for travel time calculations and full waveform methods such as the spectral element method (SEM; Komatitsch et al., 2002, Tromp et al., 2005), higher order Galerkin methods (Kaser and Dumbser, 2006; Dumbser and Kaser, 2006) and advances in more traditional Cartesian finite difference methods (e.g. Pitarka, 1999; Nilsson et al., 2007). The ability to compute seismic observables using a 3D model is only half of the challenge; models must be developed that accurately represent true Earth structure. Indeed, advances in seismic imaging have followed improvements in 3D computing capability (e.g. Tromp et al., 2005; Rawlinson and Urvoy, 2006). Advances in seismic imaging methods have been fueled in part by theoretical developments and the introduction of novel approaches for combining different seismological observables, both of which can increase the sensitivity of observations to Earth structure. Examples of such developments are finitefrequency sensitivity kernels for bodywave tomography (e.g. Marquering et al., 1998; Montelli et al., 2004) and joint inversion of receiver functions and surface wave group velocities (e.g. Julia et al., 2000).},
doi = {},
journal = {Seismological Research Letters, vol. 80, N/A, January 30, 2009, pp. 3139},
number = ,
volume = 80,
place = {United States},
year = 2008,
month =
}

The last ten years have brought rapid growth in the development and use of threedimensional (3D) seismic models of earth structure at crustal, regional and global scales. In order to explore the potential for 3D seismic models to contribute to important societal applications, Lawrence Livermore National Laboratory (LLNL) hosted a 'Workshop on MultiResolution 3D Earth Models to Predict Key Observables in Seismic Monitoring and Related Fields' on June 6 and 7, 2007 in Berkeley, California. The workshop brought together academic, government and industry leaders in the research programs developing 3D seismic models and methods for the nuclear explosion monitoring andmore »

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The development of accurate numerical methods to simulate wave propagation in threedimensional (3D) earth models and advances in computational power offer exciting possibilities for modeling the motions excited by underground nuclear explosions. This presentation will describe recent work to use new numerical techniques and parallel computing to model earthquakes and underground explosions to improve understanding of the wave excitation at the source and pathpropagation effects. Firstly, we are using the spectral element method (SEM, SPECFEM3D code of Komatitsch and Tromp, 2002) to model earthquakes and explosions at regional distances using available 3D models. SPECFEM3D simulates anelastic wave propagation in fullymore » 
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This paper describes new research being performed to improve understanding of seismic waves generated by underground nuclear explosions (UNE) by using full waveform simulation, highperformance computing and threedimensional (3D) earth models. The goal of this effort is to develop an endtoend modeling capability to cover the range of wave propagation required for nuclear explosion monitoring (NEM) from the buried nuclear device to the seismic sensor. The goal of this work is to improve understanding of the physical basis and prediction capabilities of seismic observables for NEM including source and pathpropagation effects. We are pursuing research along three main thrusts. Firstly,more » 
PROGRESS TOWARDS NEXT GENERATION, WAVEFORM BASED THREEDIMENSIONAL MODELS AND METRICS TO IMPROVE NUCLEAR EXPLOSION MONITORING IN THE MIDDLE EAST
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