CURRICULUM VITAE --------- PAUL G. RICHARDS

 


CHRONOLOGY



1943 March born in Cirencester, Gloucestershire, England
1948 to 1961 Primary and Secondary education in England
1962 to 1965 Undergraduate of Peterhouse, University of Cambridge. State Scholar. Read Part I of the Mathematical Tripos in 1963, and Part II in 1964. Won college Mathematics prize (1963), and Essay prize in Physics (1965)
1965 B.A. (Mathematics), University of Cambridge
1965 (August) to 1970 (January) Graduate student at the Seismological Laboratory of the California Institute of Technology, Graduate Research Assistant
1966 M.S. (Geology), California Institute of Technology
1966 Summer employment with Chevron Research Company (a branch of Standard Oil of California)
1970 Ph.D. (Geophysics), California Institute of Technology. Thesis title "A contribution to the theory of high frequency elastic waves, with applications to the shadow boundary of the Earth's core"
1970 (March) to 1971 Assistant Research Geophysicist, Institute of Geophysics and Planetary Physics, University of California at San Diego
1971 (July) to 1976 (June) Assistant Professor of Geological Sciences, Columbia University
1973 (November) to 1977 (June) American Editor, Geophysical Journal of the Royal Astronomical Society
1976 (July) to 1979 (June) Associate Professor of Geological Sciences, Columbia University
1977 (September) Visited Institute of Physics of the Earth, Moscow, as part of the U.S. -- U.S.S.R. Exchange Agreement on Research into Earthquake Prediction
1977 to 1978 Guggenheim Fellowship (on sabbatical leave from Columbia, spending 6 months in New Zealand)
1979 (June) to 1983 (June) Member of the Executive Committee of the Lamont-Doherty Geological Observatory
1979 (July) to 1996 Professor of Geological Sciences, Columbia University
1980 (July) to 1983 (June) Chairman, Geological Sciences, Columbia University; and Associate Director, Lamont-Doherty Geological Observatory
1980 (July) to 1983 (June) Member, NAS/NRC Committee on Seismology
1980 (September) U.S. citizenship
1982 to 1983 Member, NSF Oversight Committee on Seismology and Deep Earth Structure
1982 (October) to 1984 (June) Senate Member, Columbia University; Member of Senate Committees on Education, and External Relations and Research Policy
1983 (September) Visiting lecturer, Peking University
1984 (September) to 1985 (August) On leave from Columbia, as a William C. Foster Fellow and Visiting Scholar at the U.S. Arms Control and Disarmament Agency
1987 (July) to 1990 (June) Member, Administrative Committee of the Lamont - Doherty Geological Observatory
1987 (July) to 2008 (June) Mellon Professor of the Natural Sciences, Columbia University
1989 (June) Fellowship from the Royal Norwegian Council on Scientific and Industrial Research, visiting NORSAR
1989 to 1990 Physicist at Lawrence Livermore National Laboratory (on sabbatical leave from Columbia)
1991 First of several visits to Borovoye Geophysical Observatory, Kazakhstan, for joint research on seismic monitoring
1992 (July) to 1994 (June) President, Seismology Section, American Geophysical Union
1993 (September) to 1994 (August) On leave from Columbia, as a William C. Foster Fellow and Visiting Scholar at the U.S. Arms Control and Disarmament Agency
1994 to 1998 Member, Administrative Committee of the Lamont - Doherty Earth Observatory
1996 to 2008 Professor of Earth and Environmental Sciences, Columbia University
1997 (March-August) Visiting Scholar, at Los Alamos National Laboratory (on sabbatical leave from Columbia)
2008 (July) retired from full-time professorship, but continues to teach Columbia undergraduates, and appointed as Special Research Scientist at the Lamont-Doherty Earth Observatory.

PROFESSIONAL SERVICE (1990 and later)

 

HONORS

 

PROFESSIONAL MEMBERSHIPS

 

PUBLICATIONS

  1. T.-L. Teng and Paul G. Richards, Diffracted SH and SV, Nature, 218, 1154-1155, 1968.
  2. T.-L. Teng and Paul G. Richards, Diffracted P, SH and SV waves, and their shadow boundary shifts, Journal of Geophysical Research, 74, 1537--1555, 1969.
  3. Paul G. Richards, A contribution to the theory of high frequency elastic waves, with applications to the shadow boundary of the Earth's core, Ph.D. Thesis, California Institute of Technology, 1970.
  4. Paul G. Richards, Potentials for elastic displacement in spherically symmetric media, Journal of the Acoustical Society of America, 50, 188--197, 1971.
  5. Paul G. Richards, An elasticity theorem for heterogeneous media, with an example of body wave dispersion in the Earth, Geophysical Journal of the Royal Astronomical Society, 22, 453--472, 1971.
  6. Paul G. Richards, A theory for pressure radiation from ocean-bottom earthquakes, Bulletin of the Seismological Society of America, 61, 707--721, 1971.
  7. Paul G. Richards, Elastic wave solutions in stratified media, Geophysics, 36, 798--809, 1971.
  8. Paul G. Richards, Seismic waves reflected from velocity gradient anomalies within the Earth's upper mantle, Zeitschrift für Geophysik, 38, 517--527, 1972.
  9. Paul G. Richards, The dynamic field of a growing plane elliptical shear crack, International Journal of Solids and Structures, 9, 843--861, 1973.
  10. Paul G. Richards, Dynamic properties of an earthquake source, Proceedings of the Fifth World Conference on Earthquake Engineering, Rome, June 1973.
  11. Paul G. Richards, Calculation of body waves, for caustics and tunnelling in core phases, Geophysical Journal of the Royal Astronomical Society, 35, 243--264, 1973.
  12. Paul G. Richards, Weakly coupled potentials for high-frequency elastic waves in continuously stratified media, Bulletin of the Seismological Society of America, 64, 1575--1588, 1974.
  13. George L. Choy and Paul G. Richards, Pulse distortion and Hilbert transformation in multiply reflected and refracted body waves, Bulletin of the Seismological Society of America, 65, 55--70, 1975.
  14. Yash P. Aggarwal, Lynn R. Sykes, David W. Simpson and Paul G. Richards, Spatial and temporal variations in ts/tp and in P-wave residuals at Blue Mountain Lake, New York: Application to earthquake prediction, Journal of Geophysical Research, 80, 718--732, 1975.
  15. Paul G. Richards, Theoretical seismology, IUGG Quadrennial Report, Reviews of Geophysics and Space Physics, 13, 295--298 and 313--316, 1975.
  16. John Anderson and Paul G. Richards, Comparison of strong ground motion from several dislocation models, Geophysical Journal of the Royal Astronomical Society, 42, 347--373, 1975.
  17. Paul G. Richards, Dynamic motions near an earthquake fault: A three-dimensional solution, Bulletin of the Seismological Society of America, 60, 1--32, 1976. PDF (1.8M)
  18. Paul G. Richards and Clint W. Frasier, Scattering of elastic waves from depth-dependent inhomogeneities, Geophysics, 41, 441--458, 1976.
  19. Vernon Cormier and Paul G. Richards, Comments on a paper by Qamar and Eisenberg concerning attenuation in the Earth's outer core, Journal of Geophysical Research, 81, 3066--3068, 1976.
  20. Paul G. Richards, On the adequacy of plane-wave reflection/transmission coefficients in the analysis of seismic body waves, Bulletin of the Seismological Society of America, 66, 701--717, 1976.
  21. Vernon Cormier and Paul G. Richards, Full wave theory applied to a discontinuous velocity increase: The Earth's inner core, Journal of Geophysics, 43, 3--31, 1977.
  22. Paul G. Richards, Theoretical seismic wave propagation, IUGG Quadrennial Report, Review of Geophysics and Space Physics, 17, 312--328, 1979.
  23. Paul G. Richards, Elementary solutions to Lamb's problem for a point source and their relevance to three dimensional studies of spontaneous crack propagation, Bulletin of the Seismological Society of America, 69, 947--956, 1979.
  24. Shamita Das and Paul G. Richards, Effects of non-uniform spontaneous rupture propagation on the level and duration of earthquake ground motion, Proceedings of the Second U.S. National Conference on Earthquake Engineering, Stanford, California, 1979.
  25. Keiiti Aki and Paul G. Richards, Quantitative Seismology: Theory and Methods, two volumes, W. H. Freeman and Company, San Francisco, California, February 1980. Russian edition, 1983. Chinese edition, 1986.
  26. William H. Menke and Paul G. Richards, Crust-mantle whispering gallery phases: A deterministic model of teleseismic Pn wave propagation, Journal of Geophysical Research, 85, 5416--5422, 1980.
  27. George L. Choy, Vernon F. Cormier, Rainer Kind, Gerhard Müller and Paul G. Richards, A comparison of synthetic seismograms of core phases generated by the full wave theory and by the reflectivity method, Geophysical Journal of the Royal Astronomical Society, 61, 21--39, 1980 (and Corrigendum, 62, 733--735).
  28. David W. Simpson and Paul G. Richards (editors), Earthquake Prediction --- An International Review, 680 pages, Maurice Ewing Series #4, American Geophysical Union, 1981.
  29. William H. Menke and Paul G. Richards, On extending Biot's theory of low-frequency acoustic scatter about a rough fluid-rigid interface to more general acoustic media, Journal of the Acoustical Society of America, 71, 1101--1105, 1982.
  30. William H. Menke and Paul G. Richards, The horizontal propagation of P waves through scattering media: Analog model studies relevant to long range Pn propagation, Bulletin of the Seismological Society of America, 73, 125--142, 1983.
  31. Paul G. Richards and William H. Menke, The apparent attenuation of a scattering medium, Bulletin of the Seismological Society of America, 73, 1005--1021, 1983.
  32. Paul G. Richards, On wavefronts and interfaces in anelastic media, Bulletin of the Seismological Society of America, 74, 2157--2165, 1984.
  33. Paul G. Richards, Seismic wave propagation effects development of theory and numerical modelling, chapter in DARPA commemorative volume The VELA Program: A Twenty-Five Year Review of Basic Research, ed. A.U. Kerr, pp. 183--251, 1985.
  34. Paul G. Richards, Interpretation of the 15 January 1965 cratering explosion at Shagan River (27 pp, for U.S. Arms Control and Disarmament Agency), July 1985.
  35. Paul G. Richards, Station magnitude bias --- its existence and estimation (28 pages, for U.S. Arms Control and Disarmament Agency), August 1985.
  36. Paul G. Richards, written testimony for the House Permanent Select Committee on Intelligence, May 6, 1986. (Closed hearing -- testimony and transcript can be released only after consideration and vote of the whole committee. Subject of this invited testimony was: organization and management within the government, of the research and development of new approaches for yield determination.)
  37. Paul G. Richards, Underground nuclear testing (19 Sept. 1957), in Book of Days 1987: A Guide to Anniversaries of People and Events, ed. C.S. Johnson, pp 462--463, Pieran Press, 1987.
  38. Paul G. Richards and Allan Lindh, Toward a New Test Ban Regime, Issues in Science and Technology, National Academy of Sciences, 3, # 3, 101--108, Spring 1987.
  39. Dean Witte and Paul G. Richards, Modeling Seismic Wave Propagation in 2-D and 3-D structures, Lamont-Doherty Geological Observatory Yearbook, 64--68, 1987.
  40. Paul G. Richards, written testimony for the Senate Committee on Foreign Relations, Senate Hearing Record, January 15, 1987. Available as Senate Hearing 100-115; pp 72--86, 286--291, 325--358, and 394--396; 1987.
  41. Paul G. Richards and Joseph Nye, Weapons Testing and Nuclear Weapons Proliferation: Prospects for the Future, in Science and Security: the Future of Arms Control, Colloquium Proceedings, December 4-5, 1986 , pp. 189--218, AAAS Publication No. 87-17, 1987.
  42. Paul G. Richards, written testimony for the Senate Committee on Armed Services, Subcommittee on Strategic Forces and Nuclear Deterrence, Senate Hearing Record, February 26, 1987. Available as Senate Hearing 100-242, Pt. 4; pp 1846--1853, 1864--1872; 1987.
  43. Paul G. Richards, Consideration of Chemical Explosions, a seven-page paper delivered April 28 1987 to the Office of Technology Assessment (OTA), for incorporation in the 1988 OTA report on Seismic Verification of Nuclear Test Limitation Treaties. Richards also wrote the first draft of chapter 5 (on "Identification of Underground Nuclear Explosions") for this report (published May, 1988).
  44. Paul G. Richards, Towards Improvement in Capabilities for Seismic Monitoring of Underground Nuclear Explosions, for a conference in association with the U.N. Special Session on Disarmament, New York, May 1988.
  45. Vernon F. Cormier and Paul G. Richards, Spectral Synthesis of Body Waves in Earth Models Specified by Vertically Varying Layers, in the book Seismological Algorithms, edited by D. Doornbos, pp 3--45, Academic Press, 1988.
  46. Paul G. Richards, Stages Toward a New Test Ban, chapter 4 in the book Verification and Compliance: a Problem-Solving Approach, pp 73--91, edited by Michael Krepon and Mary Umberger, Macmillan (U.K.) and Ballinger (U.S.A.), 1988.
  47. Paul G. Richards, Nuclear Test Ban Treaties and Seismic Monitoring of Underground Nuclear Explosions: an Overview of the Historical, Technical, and Political Issues, Proceedings of the Alan S. Attardo Symposium on Science and Society, held at Yale University on April 7, 1988. 36 pages.
  48. Paul G. Richards, Seismic Methods for Verifying Test Ban Treaties, Chapter 4 of the book Nuclear Arms Technologies in the 1990's, edited by D. Schroeer and D. Hafemeister, AIP Conference Proceedings 178, pp 54--108, American Institute of Physics, New York, 1988.
  49. Paul G. Richards, Seismic monitoring of nuclear explosions, in Encyclopedia of Geophysics, ed. D.E. James, pp 1071--1089, Van Nostrand Reinhold, 1989.
  50. Paul G. Richards, Science Education for Undergraduates Goals and Roles, Lamont-Doherty Geological Observatory Yearbook, pp 26--29, 1989.
  51. Roger A. Hansen, Frode Ringdal, and Paul G. Richards, Analysis of IRIS data for Soviet nuclear explosions, NORSAR Semiannual Technical Summary, 1 October 1988 -- 31 March 1989, pp. 124--140, NTNF: Kjeller, Norway, 1989.
  52. Dean C. Witte and Paul G. Richards, The Pseudospectral Method for Simulating Wave Propagation, Computational Acoustics, Volume 3 (editors: D. Lee, A. Cakmak, R. Vichnevetsky), North-Holland, pp 1--17, 1990.
  53. Paul G. Richards and John Zavales, Seismic Discrimination of Nuclear Explosions, Annual Reviews of Earth and Planetary Sciences, 18, 257--86, 1990.
  54. Roger A. Hansen, Frode Ringdal, and Paul G. Richards, The Stability of RMS Lg Measurements and their Potential for Accurate Estimation of the Yields of Soviet Underground Nuclear Explosions, Bulletin of the Seismological Society of America, 8, 2106--2126, 1990.  PDF (1.5M)
  55. Paul G. Richards, Progress in Seismic Verification of Test Ban Treaties, IEEE Technology and Society Magazine, 9, #4, 40--52, December 1990.
  56. Paul G. Richards, testimony requested by the Senate Select Comittee on Intelligence as part of the Senate's discussion (advice and consent to ratification) of the Threshold Test Ban Treaty. Testimony appears on pp. S13741--13751 of the Congressional Record for September 25, 1990.
  57. Paul G. Richards, A short course on theoretical seismology, in Oceanographic and Geophysical Tomography, edited by Albert Tarantola, Yves Desaubies, and J. Zinn-Justin, pp 29--134, North-Holland: Amsterdam, 1990.
  58. Paul G. Richards and Frederick K. Lamb, Testing Experts rebut Robinson, Arms Control Today, p22, September 1990.
  59. Steve Taylor, Howard Patton, and Paul G. Richards, editors, Explosion Source Phenomenology, 268 pages, Geophysical Monograph #65, American Geophysical Union, Washington, DC, December 1991.
  60. Paul G. Richards, Dean Witte and Göran Ekström, Generalized Ray Theory for Seismic Waves in Structures with Planar Non-Parallel Interfaces, Bulletin of the Seismological Society of America, 81, 1309--1331, August 1991.  PDF (1.4M)
  61. Paul G. Richards, Douglas Anderson, and David Simpson, A Survey of Blasting Activity in the United States, Bulletin of the Seismological Society of America, 82, 1416--1433, June 1992. PDF (1.1M)
  62. Paul G. Richards, Won-Young Kim, and Göran Ekström, The Borovoye Geophysical Observatory, Kazakhstan, feature article in EOS, Transactions of the American Geophysical Union, 73, 201 and 205--206, May 5 1992.  PDF (217K)
  63. Paul G. Richards and Won-Young Kim, The Problem of Chemical Explosions and some Solutions, Proceedings of a Symposium on Technologies for Monitoring Nuclear Tests Related to Weapons Proliferation, pp 1936, Las Vegas, May 6--7, 1992.
  64. Paul G. Richards, report to the Nuclear Control Institute on signals from the seismic event of 1983 May 16, located in Xinjiang Province, China, 19 pages, October 1992.
  65. Frode Ringdal and Paul G. Richards, The Ukrainian event of 16 September 1979, in NORSAR Scientific Report No. 1 92/93, pp 120--124, November 1992.
  66. Cliff H. Thurber, Howard R. Quin, and Paul G. Richards, Accurate locations of nuclear explosions in Balapan, Kazakhstan, 1987 to 1989, Geophysical Research Letters, 20, 399--402, March 5, 1993.
  67. Göran Ekström and Paul G. Richards, Empirical measurements of tectonic moment release in nuclear explosions from teleseismic surface waves and body waves, Geophysical Journal International, 117, 120--140, 1994.
  68. Won-Young Kim, D.W. Simpson and Paul G. Richards, Discrimination of earthquakes and explosions in the Eastern United States using regional high-frequency data, Geophysical Review Letters, 20, 1507--1510, July 23 1993.
  69. Paul G. Richards and Won-Young Kim, Earthquakes (about 6000 words and 12 figures), The New Book of Knowledge, 1994 edition, published by Grolier.
  70. Paul G. Richards, Testing the test-ban treaty, Nature, 364, 188--189, July 15 1993. PDF (348K)
  71. Won-Young Kim, D.W. Simpson, and Paul G. Richards, High-frequency Spectra of Regional Phases from Earthquakes and Chemical Explosions, Bulletin of the Seismological Society of America, 84, 1365--1386, 1994.
  72. Paul G. Richards, Verification of a Comprehensive Test Ban Treaty - a Seismological Overview, pp 28--36 in Verification after the Cold War, edited by J. Altmann, T. Stock, J.-P. Stroot, VU University Press, Amsterdam, 1994.
  73. V. Khalturin, T. Rautian, and Paul G. Richards, A study of small earthquakes and small explosions during 1961--1989 at the Semipalatinsk Test Site, Kazakhstan, 64 page technical report for subcontract B-239589 with Regents of Univ. of Calif., 64p., March 1994.
  74. Paul G. Richards, Blasting Activity of the Mining Industry in the United States, in Proceedings of a Symposium on the Non-Proliferation Experiment: Results and Implications for Test Ban Treaties, sponsored by LLNL/Department of Energy, CONF-9404100, pp. 2-16 to 2-35, April 1994, Rockville, Maryland, ed. M.D. Denny, 1995.
  75. Paul G. Richards, Problems for CTBT Verification posed by Chemical Explosions, paper taken through inter-agency review, and presented for the United States in Geneva, June 10, 1994, CD/NTB/WP.105, 1994.
  76. John E. Vidale, Saskia Goes, and Paul G. Richards, Near-field deformation seen on distant broadband seismograms, Geophysical Research Letters, 22, 1--4, 1995.
  77. Paul G. Richards and John Zavales, Seismological methods for monitoring a CTBT: the technical issues arising in early negotiations, pages 53--81 in Monitoring a Comprehensive Test Ban Treaty, eds. E.S. Husebye and A.M. Dainty, Kluwer, Dordrecht, 836 pages, 1996.  PDF (889K) of paper as published     separate link to an updated/online version
  78. Paul G. Richards and Göran Ekström, Earthquake activity associated with underground nuclear explosions, in Inducing of Earthquakes by Underground Nuclear Explosions, NATO ASI Series, Partnership Sub-Series, 2. Environment Vol. 4, eds. R. Console and A. Nikolaev, pp 21--34, Springer Verlag, Berlin Heidelberg, 1995.
  79. Shi, Jinghua, Won-Young Kim and Paul G. Richards, Variability of crustal attenuation in the northeastern United States from Lg waves, Journal of Geophysical Research, 101, 25231--25242, 1996 (correction, 102, 11899, 1997).
  80. Shi, Jinghua, Won-Young Kim and Paul G. Richards, The stability of RMS Lg values in estimating the size of regional earthquakes in New York State and adjacent areas, submitted to Seismological Review Letters, January 1998.
  81. Kim, W.-Y., V. Aharonian, A.L. Lerner-Lam, and P.G. Richards, Discrimination of earthquakes and explosions in Southern Russia using regional high-frequency three-component data from the IRIS/JSP Caucasus network, Bulletin of the Seismological Society of America, 87, 569--588, 1997. PDF (2.4M)
  82. Song, Xiaodong, and Paul G. Richards, Seismological evidence for differential rotation of the Earth's inner core, Nature, 382, 221--224, July 18 1996. PDF (750K)
  83. Hennet, C.B., G.E. van der Vink, P. G. Richards, V.V. Adushkin, Y.F. Kopnichev, and R. Geary, Multi-use seismic stations offer strong deterrent to clandestine nuclear weapons testing, feature article in EOS, Transactions of the American Geophysical Union, 77, 289 & 300--301, July 30, 1996.
  84. Richards, Paul G., Seismological Methods of Monitoring and the International Monitoring System, in The Comprehensive Test Ban Treaty: Issues and Answers, edited by Matthew McKinzie (Proceedings of a Symposium held at Cornell University, October 11 -- 13, 1996), pp 71--89, June 1997.
  85. Shi, Jinghua, Won-Young Kim, and Paul G. Richards, The corner frequencies and stress drops of intraplate earthquakes in the Northeastern United States, Bulletin of the Seismological Society of America, 88, 531--542, 1998.
  86. Richards, Paul G., The Dallas Morning News called it A Little Extra Spin, lead article for GSAS News & Views, the newsletter of Columbia Univerity's Graduate School of Arts and Sciences, Summer 1997.
  87. Richards, Paul G., and Won-Young Kim, Testing the nuclear test-ban treaty, Nature, 389, 781--782, October 23 1997. PDFs: this Nature paper (112K); also related news stories and CIA statement (8K)
  88. Richards, Paul G., Earth Interior, in the McGraw-Hill Yearbook of Science & Technology 1999, pp 135--137.
  89. Khalturin, Vitaly I., Tatyana G. Rautian, and Paul G. Richards, The seismic signal strength of chemical explosions, Bulletin of the Seismological Society of America, 88, 1511--1524, 1998. PDF (1.3M)
  90. Shi, Jinghua, Paul G. Richards, and Won-Young Kim, Determination of seismic energy from Lg waves, Bulletin of the Seismological Society of America, 90, 483--493, 2000.
  91. Khalturin, Vitaly I., Tatyana G. Rautian, and Paul G. Richards, Magnitude distributions of mine blasting activity in different regions, technical report, 1999.
  92. Barker, Brian, Michael Clark, Peter Davis, Mark Fisk, Michael Hedlin, Hans Israelsson, Vitaly Khalturin, Won-Young Kim, Keith McLaughlin, Charles Meade, John Murphy, Robert North, John Orcutt, Chris Powell, Paul G. Richards, Richard Stead, Jeffry Stevens, Frank Vernon, Terry Wallace, Seismology: Monitoring Nuclear Tests, Science, 281, # 5385, pages 1967--1968, issue of 25 Sept 1998. PDF (120K)
  93. Richards, Paul G., Xiaodong Song, and Anyi Li, Detecting possible rotation of Earth's inner core, Science, 282, 1227a, issue of 13 November 1998 (full text is at this link to SCIENCE ).
  94. Khalturin, Vitaly I., Tatyana G. Rautian, and Paul G. Richards, A study of small magnitude seismic events during 1961 -- 1989 near and on the Semipalatinsk Test Site, Kazkhstan, Pure and Applied Geophysics, 158, 143--171, 2001. PDF (1.7M)
    also electronic supplement covering many technical details
  95. Richards, Paul G., Building the Global Seismographic Network for Test Ban Monitoring, Earth Matters, pp 37--40, Fall 1999.
  96. Li, Anyi, and Paul G. Richards, Study of inner core rotation using Novaya Zemlya nuclear explosions, a paper in Earth's Core: Dynamics, Structure, Rotation, AGU monograph, Geodynamics Series 31, Eds. V. Dehant, K. Creager, S. Zatman, and S.Karato, 23--30, 2003.
  97. Richards, Paul G., Earth's Inner Core Discoveries and Conjectures, Astronomy & Geophysics, The Journal of the Royal Astronomical Society, 41, 20--24, February 2000. Longer version available as my Jeffreys Lecture.
  98. Richards, Paul G., Seismological Methods of Monitoring Compliance with the Comprehensive Nuclear Test-Ban Treaty, Chapter 24 (pp. 369--382) of the International Handbook of Earthquake and Engineering Seismology, Part A, edited by W.H.K. Lee, H. Kanamori, and P. Jennings on behalf of the International Association of Seismology and Physics of the Earth's Interior, Academic Press, 2002. PDF (336K)
  99. V. I. Khalturin, T. G. Rautian, and P. G. Richards, Chemical Explosions during 1961--1988 on the Semipalatinsk Test Site, Kazakhstan, in Geophysics and Non-Proliferation Problems, Bulletin of the National Nuclear Center of the Republic of Kazakhstan, issue number 2, 41--44, June 2000. PDF (168K)
  100. Keiiti Aki and Paul G. Richards, Quantitative Seismology: Theory and Methods, second edition, 12 chapters in one volume, University Science Books, August 2002. Japanese edition (Kokon Shoin, Tokyo), July 2004. Chinese edition, in process, beginning August 2007. Paperback version available since April 2009 via  http://www.uscibooks.com/aki.htm
  101. George Bunn, Sidney D. Drell, Richard L. Garwin, Thomas Graham, Jr., Damien LaVera, Jack Mendelsohn (Editor), Paul G. Richards, and Amy Sands, White Paper on the Comprehensive Nuclear Test Ban Treaty, Lawyers Alliance for World Security, 81 p, Fall 2000.
  102. Xiaoping Yang, Robert North, Carl Romney, and Paul G. Richards. Worldwide Nuclear Explosions, Chapter 84 of the International Handbook of Earthquake and Engineering Seismology, edited by W.H.K. Lee, H. Kanamori, P. Jennings, and C. Kisslinger on behalf of the International Association of Seismology and Physics of the Earth's Interior, Academic Press, 2002. PDF (384K)
  103. Paul G. Richards, Commentary: future directions for global bulletins, IRIS Newsletter, vol. 2000, no. 1, 12--13, December 2000. PDF (1.3M)
  104. Paul G. Richards, Won-Young Kim, and Vitaly I. Khalturin, A Plan for Location Calibration of IMS Stations in and near Kazakhstan, Geophysics and Non-proliferation problems, issue 2, National Nuclear Centre of the Republic of Kazakhstan, June 2001. PDF (150K)
  105. Kim, Won-Young, L. R. Sykes, J. H. Armitage, J. K. Xie, K. H. Jacob, P. G. Richards, M. West, F. Waldhauser, J. Armbruster, L. Seeber, W. X. Du, and A. Lerner-Lam, Seismic waves generated by aircraft impacts and building collapses at World Trade Center, New York City, feature article in EOS, Transactions, American Geophysical Union, 82, pages 565, 570--571, November 20, 2001. PDF (756K)
  106. Li, Anyi, and Paul G. Richards, Using earthquake doublets to study inner core rotation and seismicity catalog precision, G-Cubed, 4, 1072, doi: 10.1029/200GC000379, 9 September 2003. PDF (1.6M)
  107. Granville, John P., Won-Young Kim, and Paul G. Richards, An assessment of seismic body-wave magnitudes published by the Prototype Inernational Data Centre, Seismological Review Letters, 73, 893--906, 2002.
  108. Committee on Technical Issues Related to Ratification of the Comprehensive Nuclear-Test-Ban Treaty, Technical Issues related to the Comprehensive Nuclear-Test-Ban Treaty, National Academy of Sciences, National Academy Press, 2002. (Richards wrote almost all of Chapter 2, on CTBT Monitoring Capability.) PDFs as follows: Executive Summary (156K); Introduction (112K); Stockpile Stewardship (216K); Monitoring Capability (284K); Foreign Testing (216K); All Text (1.2M); All Figures (1.6M).
  109. Paul G. Richards, On seismic sources volume changes, Deutsche Geophysikalische Gesellschaft e.V., Mitteilungen, Symposium in Memoriam of Prof. Gerhard Müller, pp 40--44, Sonderband I/2004.
  110. Waldhauser, Felix, and Paul G. Richards, Reference events for regional phases at IMS stations in China, Bulletin of the Seismological Society of America, 94, 2265--2279, December 2004. PDF (572K)
  111. Schaff, David P., and Paul G. Richards, Lg-wave cross correlation and double-difference location: application to the 1999 Xiuyan, China, sequence, Bulletin of the Seismological Society of America, 94, 867--879, 2004. PDF (480K)
  112. Yang, Zhi-xian, Felix Waldhauser, Yun-tai Chen, and Paul G. Richards, Double-difference relocation of earthquakes in central-western China, 1992--1999, Journal of Seismology, 9, 241--264, 2005. PDF (3.3M)
  113. David P. Schaff and Paul G. Richards, Repeating seismic events in China, SCIENCE, 303, 1176--1178, February 20, 2004. PDFs: (main paper, 336K); also (supplementary online material, 156K)
  114. Valeriu Burlacu, Mark Fisk, John Armbruster, Vitaly I. Khalturin, Won-Young Kim, Paul G. Richards, David P. Schaff, Felix Waldhauser, Michael West, Igor Morozov, Elena Morozova, Vernon Cormier, Anastasia Stroujkova, and Chandan Saikia, Development and Validation Testing of a Regionalized Travel-Time Model, and Source-Specific Station Corrections for Thirty IMS Stations and Other Stations in East Asia, Final Report on DTRA01-00-C-0031, 281 pages, August 2003. PDF (40M -- very large) is obtainable by ftp from ftp.ldeo.columbia.edu (then cd to pub/richards and acquire the binary file VTR_2003.pdf). A short version is available as PDF (860K)
  115. Paul G. Richards and Won-Young Kim, Equivalent volume sources for explosions at depth: theory and observations, Bulletin of the Seismological Society of America, 95, 401--407, 2005. PDF (188K)
  116. Felix Waldhauser, David Schaff, Paul G. Richards, and Won-Young Kim, Lop Nor Revisited: Underground Nuclear Explosion Locations, 1976-1996, from Double-difference Analysis of Regional and Teleseismic Data, Bulletin of the Seismological Society of America, 94, 1879--1889, October 2004. PDF (372K)
  117. Vitaly I. Khalturin, Tatyana G. Rautian, Paul G. Richards, and William S. Leith, A review of nuclear testing by the Soviet Union at Novaya Zemlya, 1955 -- 1990, Science & Global Security, 13, 1--42, 2005. PDF (2.8M)
  118. John P. Granville, Paul G. Richards, Won-Young Kim, and Lynn R. Sykes, Understanding the difference between three teleseismic mb scales, Bulletin of the Seismological Society of America, with electronic supplement, 95, 1809--1824, October 2005. PDF (460K); also online supplement (1.7M)
  119. Jian Zhang, Xiaodong Song, Yingchun Li, Paul G. Richards, Xinlei Sun, and Felix Waldhauser, Inner core differential motion confirmed by earthquake waveform doublets, Science, 309, 1357--1360, 26 August 2005. PDFs: main paper (456K); also supplementary online material (5.9M). [This latter file contains many examples of doublets in which the time shift of PKP(DF) with respect to PKP(BC) and PKP(AB) is clearly shown.]
  120. Igor B. Morozov, Elena Morozova, Scott B. Smithson, Paul G. Richards, Vitaly I Khalturin, and Leonid N. Solidilov, 3D first-arrival regional calibration model of Northern Eurasia, Bulletin of the Seismological Society of America, 95, 951--964, doi: 10.1785/0120030173, 2005. PDF (756K)
  121. Paul G. Richards, Keiiti Aki (1930 -- 2005), Seismologiste extraordinaire, Nature, 430, 1176, June 30, 2005. PDF (108K)
  122. Paul G. Richards, Keiiti Aki (1930 -- 2005), Seismologist and Leader, Seismological Research Letters, 76, 551--553, Sept./Oct. 2005. PDF (1.6M)
  123. Paul G. Richards and Anyi Li, Inner core rotation, pages 423--425 in Encyclopedia of Geomagnetism and Paleomagnetism, eds. David Gubbins and Emilio Herrero-Bervera, Encyclopedia of Earth Sciences Series, general editors Rhodes Fairbridge and Michael Rampino, Springer, 2007. PDF (40K)
  124. Paul G. Richards, Felix Waldhauser, David Schaff, and Won-Young Kim, The applicability of modern methods of earthquake location, Pure and Applied Geophysics, 165, 351--372, 2006. PDF (1M)
  125. Paul G. Richards, Uses of Seismic Data and the Importance of Open Access to Major Data Centers in Seismology, pp 78 -- 79 in "Strategies for Preservation of and Open Access to Scientific Data in China," National Research Council Report, 2006.
  126. Paul G. Richards, Forensic Seismology and CTBT verification, feature article in CTBTO Spectrum, issue no. 9, pages 1, 6, and 14, January 2007. PDF (764K)
  127. Paul G. Richards and Won-Young Kim, Commentary: Seismic Signature, Nature Physics, 3, 4--6, January 2007. PDF (616K)
  128. Won-Young Kim and Paul G. Richards, North Korean Nuclear Test: Seismic Discrimination at Low Yield, feature article in EOS, Transactions of the American Geophysical Union, 88, no. 14, pages 157 and 161, 3 April 2007. PDF (468K)
  129. Michael Hamburger, Yuri Kopnichev, Anatoli Levshin, Vladislav Martynov, Natalya Mikhailova, Peter Molnar, Paul G. Richards, Steve Roecker, David Simpson, Brian E. Tucker, Robert Wesson, In Memoriam Vitaly Ivanovich Khalturin, Seismological Review Letters, 78, 577--578, issue of Nov/Dec 2007. link to this article and other articles and images in memory of Vitaly
  130. Paul G. Richards, CTBT Monitoring: a vital activity for our profession, Seismological Review Letters, 79, 375--378, May/June, 2008. PDF (184K)
  131. Jian Zhang, Paul G. Richards, and David Schaff, Wide-scale detection of earthquake waveform doublets and further evidence for inner core super-rotation, Geophysical Journal International, 174, 993–1006, doi: 10.1111/j.1365-246X.2008.03856.x, 2008. PDF (1.9M)
  132. Paul G. Richards and Won-Young Kim, Analysis of digital seismograms from nuclear explosions across forty years, Proceedings of Fifth International Conference (held at Borovoye, Kazakhstan, August 2008) on Monitoring of nuclear tests and their consequences, seven pages, Vestnik, 2008. PDF (288K)
  133. Paul G. Richards and Won-Young Kim, Monitoring for Nuclear Explosions, Scientific American, 300, 70–77, March 2009. PDF (156K)
  134. John J. Zucca, William R. Walter, Arthur Rodgers, Paul G. Richards, Michael Pasyanos, Stephen C. Myers, Thorne Lay, Dave Harris, and Tarabay Antoun, The prospect of using three-dimensional Earth models to improve nuclear explosion monitoring and ground motion hazard assessment, Seismological Research Letters, 80, 31–39, January/February, 2009. PDF (1.8M)
  135. Lynn R. Sykes and Paul G. Richards, Seismology, in Science for Security, Verifying the Comprehensive Nuclear-Test-Ban Treaty, pages 5--10, Public Information Preparatory Commission for the CTBTO, 2009. PDF (1.2M)
  136. Won-Young Kim, Paul G. Richards, Diane Baker, Howard Patton, and George Randall, Improvements to a Major Digital Archive of Seismic Waveforms from Nuclear Explosions, Final Report AFRL-RV-HA-TR-2010-1024, Air Force Research Laboratory, 127 pages, 23 March 2010. PDF (8.9M)
  137. David P. Schaff and Paul G. Richards, Studies of Repeating Earthquakes in China, Research and Technology Review, National Nuclear Center of the Republic of Kazakhstan, Issue 3(43), 149–151, September 2010. PDF (688K)
  138. James N. Brune and Paul G. Richards, Harry Fielding Reid Medal, Citation and Response, Seismological Research Letters, 81, 820–822, September/October, 2010.  PDF (970K)
  139. Paul G. Richards and Zhongliang Wu, Seismic Monitoring of Nuclear Explosions, in Encyclopedia of Solid Earth Geophysics, ed. Harsh Gupta, Encyclopedia of Earth Sciences Series, pages 1144 to 1156, Springer: Dordrecht, The Netherlands, 2011.
  140. Zhongliang Wu and Paul G. Richards, Seismology, Monitoring of CTBT, in Encyclopedia of Solid Earth Geophysics, ed. Harsh Gupta, Encyclopedia of Earth Sciences Series, pages 1340 to 1344, Springer: Dordrecht, The Netherlands, 2011.
  141. David P. Schaff and Paul G. Richards, On finding and using repeating seismic events in and near China, Journal of Geophysical Research–Solid Earth, vol. 116 (20 pages), B03309, doi:10.1029/2010JB007895, 2011.  link to this AGU/JGR publication

 

UNPUBLISHED MSS that have some merit

  1. Paul G. Richards' write-up of the original job description (and ad) for IRIS President, late 1983.
  2. Paul G. Richards, Tutorial on Estimation of Nuclear Explosion Yield using Seismic Methods, 35 pages, 1986.
  3. Paul G. Richards, Analysis of the 15 January 1965 Cratering Explosion at Shagan River, Eastern Kazakhstan, and Implications for estimating the Yields of subsequent large Nuclear Explosions at the Shagan River Test Site, 20 pages, 1986.
  4. Dean Witte and Paul G. Richards, The Stability and Accuracy of Pseudospectral Simulations of Wave Propagation, intended for submission to Wave Motion (chapter of Dean Witte's thesis, but he never submitted it).
  5. Dean Witte and Paul G. Richards, A Hybrid Wave Propagation Method for Irregular Inclusions Within Regular Media, intended for submission to Journal of the Acoustical Society of America (chapter of Dean Witte's thesis, but he never submitted it).
  6. Paul G. Richards, Calculation of body-wave pulse shapes, with allowance for frequency-dependent Q, in AFGL-TR-87-0049, a technical report to the Air Force Geophysics Laboratory, 15 February 1987.
  7. Paul G. Richards, Verification of Nuclear Test Ban Treaties -- an Example of Interaction between Technical and Political Perspectives, paper for a Princeton University symposium on Geology and Society, February 1989.
  8. Paul G. Richards, Opening Remarks and Closing Remarks, for DOE/LLNL Symposium on Explosion Source Phenomena, March 14--16, 1989.
  9. Paul G. Richards, Nuclear Test Ban Treaties and Seismic Monitoring of Underground Nuclear Explosions: an Overview of Historical, Technical, and Recent Political Issues, 73 pages, 1990.
  10. Paul G. Richards, Peace. 1990
  11. Paul G. Richards, Management Plan for the Joint Seismic Program (US -- USSR), April 1991.
  12. Paul G. Richards, D. A. Anderson and D. W. Simpson, A Survey of Blasting Activity in the United States. Scientific report to AFPL, May 1991.
  13. Paul G. Richards and Won-Young Kim, Preliminary Assessment of Newly Available Digital Seismic Data from Kazakhstan. Scientific report to AFPL, September 1991.
  14. Paul G. Richards, How can the Operation of Thousands of Seismic Stations (Carried out by Hundreds of Institutions in Tens of Countries) best be focussed on Discrimination Research? Invited lecture (written as 9 pages) for DARPA/Air Force annual meeting on Seismic Verification (October 1991).
  15. P.G. Richards, W.-Y. Kim, D.W. Simpson, and G. Ekström, Chemical Explosions and the Discrimination Problem, PL-TR-91-2285, final technical report to Phillips Laboratory, 26 November 1991.
  16. Paul G. Richards and Göran Ekström, Report of a visit to the Borovoye Geophysical Observatory, circa 1991. Appendix: memo to file, on information about Borovoye.
  17. Won-Young Kim, P. G. Richards and Jinghua Shi, Studies of RMS Lg Data. July 1992.
  18. Paul G. Richards. SPOT picks of nuclear explosion locations on the Balapan test site, near Semipalatinsk, Kazakhstan (these picks were in a report to AFPL, and also on the CD "Nuclear Explosion Database Volume 1: Balapan" compiled by Maxwell Laboratories, Inc., S-CUBED Division, January 1993.
  19. Paul G. Richards, How can seismology best contribute to the prevention of a proliferation of nuclear weapons? (19 pages, July 1993).
  20. P.G. Richards, W.-Y. Kim and G. Ekström, RMS Lg studies of underground nuclear explosions in the U.S.S.R. and the U.S., PL-TR-93-2227, final technical report to Phillips Laboratory, 19 August 1993 includes my papers ##67, 68, 78, plus SPOT picks at Balapan, and Lg signals recorded in China, and RMS Lg measurements of Balapan explosions using Borovoye data.
  21. Paul G. Richards, Verification of a Comprehensive Test Ban Treaty -- the Potential Contribution of Seismological Methods (13 pages, Fall 1993).
  22. Paul G. Richards, Seismicity induced by Nuclear Explosions, excerpt from technical report PL-TR-93-2227, 1993.
  23. Paul G. Richards, A role of IRIS in public policy, in IRIS 2000, proposal to NSF, written in Spring 1995 and circulated later in 1995.
  24. Paul G. Richards and Won-Young Kim, The merits of digital versus analog methods of recording seismic motion, paper in Proceeding Volume of the first China -- Korea workshop on digital seismology, Seoul, S. Korea, January 1996.
  25. Vitaly I. Khalturin, Tatyana G. Rautian, Paul G. Richards, and Won-Young Kim, Evaluation of Chemical Explosions and Methods of Discrimination for Practical Seismic Monitoring of a CTBT, AFRL-VS-HA-TR-98-0012, final report, Dec 1997.
  26. Alexander F. Emanov, Albina G. Filina, Vitaly I. Khalturin, Won-Young Kim and Paul G. Richards, Available data on large chemical explosions east of Novosibirsk, Proceedings, 1st workshop on IMS Location Calibration, Oslo, Norway 12 ­ 14 January 1999.
  27. Paul G. Richards, Accurate estimates of the absolute location of underground nuclear tests at the northern Novaya Zemlya Test Site, Proceedings, 2nd Workshop on IMS Location Calibration, Oslo, Norway 20 - - ­ 24 March 2000.
  28. Paul G. Richards, A plan for seismic location calibration of 30 IMS stations in Eastern Asia, Proceedings, 2nd Workshop on IMS Location Calibration, Oslo, Norway 20 ­ 24 March 2000.
  29. Paul G. Richards, Answers to questions on correlation analysis, submitted to the Bureau of Arms Control, US Dept. of State, June 28, 2000.
  30. Won-Young Kim, Paul G. Richards, Vitaly V. Adushkin, and Vladimir Ovtchinnikov, Borovoye digital seismogram archive for underground nuclear tests during 1966 ­ 1996, technical report, April 2001.
  31. W.-Y. Kim, G. L. Vsevolozhsky, T. L. Mulder, and P. G. Richards, Practical analysis of seismic activity in Northwestern China during September 4 -- 7, 1995, technical report sponsored by AFOSR.
  32. Paul G. Richards, Comparison of teleseismic body-wave magnitudes published by the Prototype International Data Centre, the U.S. Geological Survey, and the International Seismological Centre, part of a Final Report to DTRA, December 2002.
  33. Paul G. Richards, Seismology and CTBT Verification, Background Paper #4, for Stanford Roundtable Discussion on the CTBT, July 19, 2000.
  34. Paul G. Richards, Earth Structure Near Core Boundaries, GeoDynamics meeting, London, Ontario, September 2-5, 1979.
  35. Liping Gao and Paul G. Richards, Studies of Earthquakes On and Near the Lop Nor, China, Nuclear Test Site , Annual DOD Seismic Research Review, 1994 or 1995.
  36. Vitaly I. Khalturin, Paul X. Richards, Won-Young Kim, Analysis of the Nilore, Pakistan, seimograms of the Indian nuclear explosions of 1998 May 11, Annual DOD Seismic Research Review, 1998.
  37. Vitaly I. Khalturin, Won-Young Kim, and Paul G. Richards, Magnitude Distributions of Mine-Blasting Activity, and Characteristics of Regional Seismograms at Distances in the Rang 680-800 km, DOD Seismic Research Review, ~1999.
  38. Paul G. Richards, Statement by PGR, as a candidate for election to the Board of Directors of the American Association for the Advancement of Science, circa 2001.
  39. Paul G. Richards, John Armbruster, Valeriu Burlacu, Vernon F. Cormier, Mark D. Fisk, Vitaly I. Khalturin, Won-Young Kim, Igor B. Morozov, Elena A. Morozova, Chandan K. Saikia, David Schaff, Anastasia Stroujkova, and Felix Waldhauser, Seismic Location Calibration for 30 International Monitoring System Stations in Eastern Asia: Final Results, DOD/DOE Seismic Research Review, Tucson, 2003.
  40. Won-Young Kim, David P. Schaff, Jian Zhang, Felix Waldhouser, and Paul G. Richards, Evaluation of Cross-Correlation Methods on a Massive Scale for Accurate Relocation of Seismic Events, DOD/DOE Seismic Research Review, Orlando, September 2004.
  41. Tatyana G. Rautian, Vitaly I. Khalturin, W. Scott Phillips, and Paul G. Richards, Explosion Source Phenomena using Soviet Test Era Waveform Data, DOD/DOE Seismic Research Review, Orlando, September 2004.
  42. Paul G. Richards, Won-Young Kim, Mike Hagerty, Vitaly Khalturin, Tatyana G. Rautian, and Pavel Martysevich, Integrated Study of Seismic and Infrasonic Signals from Sources in Southern Siberia, Eastern Kazakhstan and Western China, Final Report DTRA (Defense Threat Reduction Agency), July 2004.
  43. Paul G. Richards, Seismicity in the vicinity of the Lop Nor test site, Xinjiang Provice, China, Appendix to a technical report I wrote in about 1995.

 

 

RESEARCH SUMMARY

In general: Interests in quantitative seismology including development and application of theoretical (“synthetic”) seismograms to the interpretation of observations; and improvements in methods to characterize seismicity (better detections, and better estimation of locations, moment tensors, and fault orientation and slip).  Interests in seismic monitoring for nuclear explosions, and in the development of precision methods applied to large waveform archives for broad improvements in bulletins of seismicity.

 

More specifically:  Investigation of microearthquakes along the San Andreas; techniques of digital data analysis; theoretical study of diffraction phenomena in model experiments; use of potentials for elastic displacement in heterogeneous media; study of body waves near the Earth's core shadow boundary — their amplitudes, dispersion, and effective shadow shift; study of elastic wave propagation in spherically symmetric media; calculation of reflection coefficients for various heterogeneities, and deductions (from published data on precursors to P'P') for structure in the upper mantle; use of Cagniard-de Hoop methods, for moving sources, to study ocean-bottom earthquakes; representation theorems for the solution of motion due to faulting in a heterogeneous elastic medium; development of elastic wave solutions in media with second-order discontinuities; derivation and evaluation of an exact solution for dynamic effects of a growing elliptical shear crack, for which shear stress is a constant times the normal stress; relations between particle velocity on a fault surface, and stress drop; calculation of frequency-dependent effects in body waves passing through the Earth's core, and deductions for structure in the lowermost mantle; source theory for earthquakes; tunnelling of seismic body waves; demonstration, from data on the Blue Mountain Lake swarm of 1971, that the P-wave velocity is fluctuating more than the S-wave velocity, and in a manner suggesting control by dilatancy; analysis of reflection seismograms, with relevance to prospecting; investigation of temperature rise, on a fault surface undergoing earthquake motions; derivation of a closed-form analytic solution for the surface of a half-space subjected to a surface force; determination of the slip function for faulting in a medium with given distribution of initial stress and strength; computation of seismic waves in media composed of inhomogeneous layers, with a correct account of the effects of attenuation; consistency checks, on measurements of Earth strain; analysis of the apparent Q resulting from scattering when a seismic wave propagates many wavelengths through a medium with inhomogeneity on all spatial scales; estimation of station magnitude bias; numerical methods (especially the pseudo-spectral method) for studying elastic and anelastic wave propagation in 3-D; analytical methods for seismic wave propagation in 3-D structures composed of homogeneous layers with randomly-dipping interfaces; seismic methods for studying underground nuclear explosions (detection capability and yield estimation); Earth noise at high frequency; study of charge sizes and size distribution of chemical explosions; discrimination between large chemical and small nuclear explosions; tectonic release from underground nuclear explosions; stability of RMS Lg amplitudes, and their use for estimating yields of underground explosions; asymptotic structure of normal modes, using uniform asymptotic theory; earthquakes induced by nuclear explosions, in the context of on-site inspection of a suspicious event under a CTBT; studies of small earthquakes and small explosions at the Semipalatinsk Test Site, Kazakhstan; uses of spectral ratios to discriminate between small earthquakes and small explosions from signals recorded at regional distances; interpretation of far-field and intermediate-field P-waves from deep earthquakes; "near-field" deformation seen in broadband seismograms; discovery of seismological evidence for differential rotation of the Earth's inner core; empirical methods to improve estimates of event location using ground truth data to obtain corrected regional travel times; uses of earthquake and explosion doublets for precision studies of inner core rotation and evaluation of catalog precision.