During three months in 1997 Dr. Griscom was a Fulbright-García Robles Fellow at
Universidad Nacional Autónoma de México in Mexico City, where he chose to initiate ESR
studies of debris from the bolide impact 65 million years ago that created the 180-km-
diameter Chicxulub crater buried 1 km beneath México’s Yucatán peninsula (discovered by
others in the early 1990’s and now nearly universally believed to mark the event responsible
for the extinction of the dinosaurs). In 2001 Griscom extended his studies of these materials
while Professeur Invité at Laboratoire Minéralogie–Cristallographie de Paris at Université de
Paris 6, Paris, France. The culmination of this research was a 41-page chapter by Griscom,
V. Beltrán-López, K. Pope, and A. Ocampo in the 3rd volume (2003) of the Springer
monograph series, Impact Studies.
Universidad Nacional Autónoma de México in Mexico City, where he chose to initiate ESR
studies of debris from the bolide impact 65 million years ago that created the 180-km-
diameter Chicxulub crater buried 1 km beneath México’s Yucatán peninsula (discovered by
others in the early 1990’s and now nearly universally believed to mark the event responsible
for the extinction of the dinosaurs). In 2001 Griscom extended his studies of these materials
while Professeur Invité at Laboratoire Minéralogie–Cristallographie de Paris at Université de
Paris 6, Paris, France. The culmination of this research was a 41-page chapter by Griscom,
V. Beltrán-López, K. Pope, and A. Ocampo in the 3rd volume (2003) of the Springer
monograph series, Impact Studies.
Using mostly the technique of electron spin resonance (ESR) spectrometry, Griscom was
responsible for the discovery and/or extensive characterization of nearly all known intrinsic
and extrinsic point defects in pure and B-, Ge-, and P-doped silica, alkali silicate and borate
glasses, and heavy-metal fluoride glasses, as well as experimental and theoretical
advances in characterizing fine-grained ferromagnetic precipitates in glasses. His principal
research interest since 1973 has been radiation-induced point defects in amorphous silica
(a-SiO2). His studies of radiation-induced atomic hydrogen in a-SiO2 with H2O impurities
led him in 1986 to propose the now-universally-accepted “hydrogen model" for the buildup of
radiation-induced interface states in metal-oxide-semiconductor (MOS) structures used for
computer chips. This activity catalyzed Griscom’s subsequent discovery and characterization
of self-trapped holes (STHs) in silica.
From 1993 through 1996, his research centered on radiation hardening of pure-silica-core
optical fibers for monitoring fusion-reactor plasmas, while from 1996 to 1999 he was
Principal Investigator on a Department-of-Energy-sponsored program to investigate
possible radiation-induced decomposition of candidate glasses for nuclear waste disposal.
Last year he reanalyzed his 1999 data for a unique then-17-year-old simulated plutonium-
immobilization glass containing selected amounts of the highly radioactive isotope Pu-238.
He presented these results as an invited paper at the symposium "SiO2, Advanced
Dielectrics and Related Devices", held in Saint-Etienne, France, in 2008, and has recently
submitted a long article on this subject to the Journal of Non-Crystalline Solids.
In 2000 he devised fractal kinetics formalisms that he used to analyze the production and
decay of radiation-induced defect centers in both pure and germanium-doped silica-core
optical fibers, discovering in the process some totally unexpected, and undoubtedly useful,
empirical rules for the dependencies of the rate constants on dose rate.
responsible for the discovery and/or extensive characterization of nearly all known intrinsic
and extrinsic point defects in pure and B-, Ge-, and P-doped silica, alkali silicate and borate
glasses, and heavy-metal fluoride glasses, as well as experimental and theoretical
advances in characterizing fine-grained ferromagnetic precipitates in glasses. His principal
research interest since 1973 has been radiation-induced point defects in amorphous silica
(a-SiO2). His studies of radiation-induced atomic hydrogen in a-SiO2 with H2O impurities
led him in 1986 to propose the now-universally-accepted “hydrogen model" for the buildup of
radiation-induced interface states in metal-oxide-semiconductor (MOS) structures used for
computer chips. This activity catalyzed Griscom’s subsequent discovery and characterization
of self-trapped holes (STHs) in silica.
From 1993 through 1996, his research centered on radiation hardening of pure-silica-core
optical fibers for monitoring fusion-reactor plasmas, while from 1996 to 1999 he was
Principal Investigator on a Department-of-Energy-sponsored program to investigate
possible radiation-induced decomposition of candidate glasses for nuclear waste disposal.
Last year he reanalyzed his 1999 data for a unique then-17-year-old simulated plutonium-
immobilization glass containing selected amounts of the highly radioactive isotope Pu-238.
He presented these results as an invited paper at the symposium "SiO2, Advanced
Dielectrics and Related Devices", held in Saint-Etienne, France, in 2008, and has recently
submitted a long article on this subject to the Journal of Non-Crystalline Solids.
In 2000 he devised fractal kinetics formalisms that he used to analyze the production and
decay of radiation-induced defect centers in both pure and germanium-doped silica-core
optical fibers, discovering in the process some totally unexpected, and undoubtedly useful,
empirical rules for the dependencies of the rate constants on dose rate.
David L. Griscom Ph.D. is a Research physicist, retired in 2001 from Naval Research
Laboratory (NRL) in Washington, DC, after 33 years service, including 3 years as half-time
Program Manager at the Defense Advanced Research Projects Agency in Arlington, VA.
He is a Fellow of the American Physical Society, the American Association for the
Advancement of Science, and the American Ceramic Society; and he was a Fulbright-García
Robles Fellow at Universidad Nacional Autónoma de México in Mexico City in 1997.
Between 2000 and 2004, Griscom held visiting professorships of research at the
Universities of Paris-6&7, Lyon-1, and Saint-Etienne, France, and Tokyo Institute of
Technology. He was Adjunct Professor of Materials Science and Engineering, University of
Arizona from 2004 to 2005. The winner of the 1993 N.F. Mott Award sponsored by the
Journal of Non-Crystalline Solids, the 1995 Otto Schott Award offered by the
Carl-Zeiss-Stiftung (Germany), a 1996 Outstanding Graduate School Alumnus Award at
Brown University, and the 1997 Sigma Xi Pure Science Award at NRL, Griscom is principal
author of 109 of his 189 published works, a body which is highly cited by his peers
according to his score (h=39) on the recently devised
Laboratory (NRL) in Washington, DC, after 33 years service, including 3 years as half-time
Program Manager at the Defense Advanced Research Projects Agency in Arlington, VA.
He is a Fellow of the American Physical Society, the American Association for the
Advancement of Science, and the American Ceramic Society; and he was a Fulbright-García
Robles Fellow at Universidad Nacional Autónoma de México in Mexico City in 1997.
Between 2000 and 2004, Griscom held visiting professorships of research at the
Universities of Paris-6&7, Lyon-1, and Saint-Etienne, France, and Tokyo Institute of
Technology. He was Adjunct Professor of Materials Science and Engineering, University of
Arizona from 2004 to 2005. The winner of the 1993 N.F. Mott Award sponsored by the
Journal of Non-Crystalline Solids, the 1995 Otto Schott Award offered by the
Carl-Zeiss-Stiftung (Germany), a 1996 Outstanding Graduate School Alumnus Award at
Brown University, and the 1997 Sigma Xi Pure Science Award at NRL, Griscom is principal
author of 109 of his 189 published works, a body which is highly cited by his peers
according to his score (h=39) on the recently devised
Career Overview
| David L. Griscom, Ph.D. Physicist, Consultant |
Long-Term Research Specializations and Accomplishments
Recent Forays into Impact Geology
| Footnotes to photos at top. (2000) Dave Griscom and Pavle Premovic (Director, Laboratory for Geochemistry, Cosmochemistry & Astrochemistry, University of Nis, Serbia) with ESR spectrometer at Universite de Paris-6. (2001) Dave at Planetary Society expedition to Chicxulub crater ejecta outcrops, Albion Island, Belize. (2002) Dave in practice jersey of Mandai Memorials Hockey Club, Tokyo. (2007) Dave at GSA Penrose Conference on The Late Eocene Earth, Parc del Conero, Italy |
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In August 2003, Griscom and eight colleagues from labs in the U.S., France, and Japan
published in the proceedings of the international conference “Natural Glasses-4” an
unprecedentedly thorough materials-science characterization of the iron-oxide-welded
quartzite pebbles and cobbles of “upland deposits” of eastern Virginia, southern Maryland,
and Washington, DC, concluding that these rocks have no other interpretation than as being
ejecta from the 35.5-million-year-old, 90-km-diameter Chesapeake Bay crater (discovered
by scientists at the U.S. Geological Survey in the early 1990’s). Griscom presented his
purely geological evidence for the same conclusion at numerous geological meetings and
seminars over the past 10 years, culminating with the 2007 Geological Society of America
Penrose Conference on The Late Eocene Earth in Monte Cònero, Italy. Believing his
manuscript submitted for the conference proceedings to have been unfairly rejected and
sensing wide spread opposition to his conclusions even though no serious errors in his
work have ever been identified, he decided to web published it here for the benefit of anyone
interested.
published in the proceedings of the international conference “Natural Glasses-4” an
unprecedentedly thorough materials-science characterization of the iron-oxide-welded
quartzite pebbles and cobbles of “upland deposits” of eastern Virginia, southern Maryland,
and Washington, DC, concluding that these rocks have no other interpretation than as being
ejecta from the 35.5-million-year-old, 90-km-diameter Chesapeake Bay crater (discovered
by scientists at the U.S. Geological Survey in the early 1990’s). Griscom presented his
purely geological evidence for the same conclusion at numerous geological meetings and
seminars over the past 10 years, culminating with the 2007 Geological Society of America
Penrose Conference on The Late Eocene Earth in Monte Cònero, Italy. Believing his
manuscript submitted for the conference proceedings to have been unfairly rejected and
sensing wide spread opposition to his conclusions even though no serious errors in his
work have ever been identified, he decided to web published it here for the benefit of anyone
interested.
Paris, 2000 Belize, 2001 Tokyo, 2002 Italy, 2007
or go here to view his LinkedIn profile.