FOIA: Seismic wave radiation, propagation and event location in laterally heterogeneous media, page 1

Table of Contents

List of Contributing Scientis - v
List of Previous and Related Contracts - v
Bibliography of Publications Totally or Partially Supported by the Contract- vi
Preface - vii
Multiple Multipole Expansions for Elastic Scattering - 1

Abstract - 1
Introduction – 2
Theoretical Background – 3
Numerical Results – 8
Discussion – 12
Acknowledgements – 14
References – 15
Figures – 17

Relocation of Explosions at the Balapan, Kazakhstan Test Site - 27

Summary – 27
Introduction – 27
Data Processing – 28
Relocation Results and Conclusions – 33
References – 35
Figures – 37

Multiple Radiation of Seismic Waves from Explosions in Non-spherical Cavities and its Application of Signal Identification – 47

Abstract – 48
Introduction – 49
Spherical Mapping Approximation – 53

Application to Realistic Cavity Shape – 58
Long-Wave Approximation and Corresponding Source Moment Tensor – 60
Surface Waves from explosions in an Underground Cavity – 65
Numerical Results for Radiation Patterns of Body and Surface Waves – 69
Discussion – 73
Acknowledgments – 75
References – 76
Legend of Figures – 79
Appendix A: Fundamental Elastodynamic Vectors, Associated Functions, and Coordinate Transformation Relations – 81
Appendix B: Quadrature of the Cavity Integrals – 86
Figures – 88

The project on which the report is based had three objectives. The first was to develop new methods for modeling regional wave propagation in laterally heterogeneous media. Toward this end we developed some new computational techniques for seismic wave scattering based on the boundary element method and multipole expansions. This report includes a preprint of a paper entitled, "Multiple multipole expansions for elastic scattering," which has been submitted to Journal of the Acoustical Society of America.

The second objective was to develop techniques for relative event location and apply them to problems of nuclear monitoring. The second part of this report is the application of a relative event location method we developed, based on waveform cross-correlation, to the location of presumed explosions at the Balapan, Kazakhstan Test Site. Events at this test site have been located very accurately on the basis of satellite images, and this provides the opportunity to test the accuracy of our approach and compare it to the location accuracy achievable with conventional seismic techniques.

The third objective was to study the effects of non-spherical cavities on the seismic wave radiation from explosions.