237:. In addition, Krogh's laboratory methods for the dissolution of minerals and the subsequent chemical separation of trace quantities of uranium and lead resulted in a significant reduction of environmental Pb contamination (blank) to ultra-low levels, and permitted increasingly small quantities of mineral grains and sub-grain domains to be analyzed. In the mid-1980s, he was instrumental in producing a synthetic 205Pb isotopic tracer (spike) that was distributed for use in U-Pb geochronology laboratories worldwide. The application of Krogh's novel and innovative techniques has revolutionized U-Pb geochronology and permitted the ages of rocks to be determined with unprecedented accuracy and precision. Most of what is known of the Earth's 4.5 billion-year history has been placed in precise geological sequence using these dating methods.
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Krogh's main focus of research has been geochronology, an effort which has long involved the integration of field work (particularly in high-grade gneisses of the
Grenville Province) with clean-laboratory isotope dilution techniques. With uranium-lead (U-Pb) dating he developed a simple, yet
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innovative air-abrasion technique for removing exterior portions of minerals that may have suffered Pb-loss, which, combined with improved magnetic separation methods, greatly improved the accuracy and precision of
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rocks. Krogh's techniques have become the international de facto standard. The application of these techniques has provided a detailed understanding of the evolution of the Earth's
Precambrian shield areas.
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In 1975, Krogh returned to Canada to work as the
Associate Curator/Director of the Royal Ontario Museum's Geochronology Laboratory. In 1976, he became a professor in the Geology Department of the
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331:. In Earth Processes: reading the isotopic code. A. Basu and S. Hart, eds. Geophysical Monograph 95, Washington, D.C.: American Geophysical Union, pp. 343–353.
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with the development of new laboratory procedures and analytical methodologies. His discoveries have yielded an unprecedented level of precision in the dating of
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Shock metamorphosed zircons with correlated U-Pb discordance and melt rocks with concordant protolith ages indicate an impact origin for the
Sudbury Structure
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Precise zircon geochronology on
Archean rocks sampled by the world's deepest continental borehole, SD-3 Superdeep Well, Kola Peninsula, Russia
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Augmented and reassessed U-Pb geochronological data from the
Labradorian-Grenvillian front in the Smokey archipelago, eastern Labrador
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156:, where he continued to work whenever he was not studying. His first job was as a Teaching Assistant in Mineralogy, then as a
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as a
Geological Assistant. In 1959, he was a Senior Assistant for the Ontario Department of Mines. Krogh obtained a
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317:. In Reviews in Mineralogy and Geochemistry, J.M. Hanchar and P.W.O. Hoskin (Editors) volume 53, p. 145-181.
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Improved accuracy of U-Pb zircon ages by the creation of more concordant systems using an air abrasion technique
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dating of minerals and rocks. In 1970, he switched to specializing in the
Uranium-Lead dating of
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High precision U-Pb ages of single zircons and parts of zircon in simple and complex populations
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until 1964 when he became a
Scientific Staff Member. From 1964 to 1970, he specialized in
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and held several jobs. For the first two summers he worked as a
Geological Assistant at
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U-Pb ages of single shocked zircons linking distal K/T ejecta to the Chicxulub crater
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366:. M.Sc. Thesis, Department of Geology, Queen's University, Kingston, Ontario.
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Krogh, T.E., Kamo, S.L., Sharpton, V., Marin, L. and Hildebrand, A.R. 1993.
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1995, became a distinguished fellow of the Geological Association of Canada
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In 1979, he returned to the Royal Ontario Museum to be their Full Curator.
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214:. In 1978, he shifted to be Graduate Faculty Member with the university.
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in geology from the university in 1960. He left Canada to study at the
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Chen, Y. D., Krogh, T. E., Vetrin, V. R. and Mitrofanov, F. P. 1994.
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132:. Between 1955 and 1959, he studied geological engineering at
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Mineralogical Association of Canada- Past President's Medal
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The titaniferous magnetite deposit of the Newboro District
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Krogh, T.E., Kamo, S.L., Gower, C. and Owen, J.V., 2002.
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University of Toronto Geology Division Alumni Newsletter
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Members of the Norwegian Academy of Science and Letters
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1991, bestowed an honorary D.Sc. by Queen's University
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University of Victoria- Duo Honoured by Royal Society
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Geological Society of America Newsletter- March 1993
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359:. Geochimica et Cosmochimica Acta 46: 637-649.
386:ROM Curator inducted into Royal Society of Canada
324:. Canadian Journal of Earth Sciences 39: 831–843.
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313:Davis, D.W., Williams, I.S., Krogh, T.E., 2003.
284:1996, awarded the Past President's Medal by the
46:but its sources remain unclear because it lacks
315:Historical development of zircon geochronology
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710:Massachusetts Institute of Technology alumni
327:Krogh, T.E., Kamo, S.L. and Bohor, B. 1996.
730:Academic staff of the University of Toronto
180:Between 1964 and 1975, Krogh worked at the
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290:1997, became a Geochemistry Fellow of the
755:Fellows of the American Geophysical Union
77:Learn how and when to remove this message
277:Norwegian Academy of Science and Letters
705:Fellows of the Royal Society of Canada
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300:1999, became an elected fellow of the
275:1994, became an elected member of the
720:Queen's University at Kingston alumni
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338:. ICOG-8 Program with Abstracts, 56..
154:Massachusetts Institute of Technology
108:. He revolutionized the technique of
449:When did the Earth Begin? Ask a Rock
396:Queen's University- Honorary degrees
296:European Association of Geochemistry
96:(1936 – April 29, 2008) was a
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401:American Geophysical Union- Fellows
286:Mineralogical Association of Canada
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164:, then as a Research Assistant in
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715:People from Peterborough, Ontario
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188:He was a post-doctoral fellow in
700:20th-century Canadian geologists
252:Geological Association of Canada
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224:project between 1991 and 1996.
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680:2022: Philippe Van Cappellen
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438:Retrieved on March 25, 2013
256:1990, made a fellow of the
168:. In 1964, he obtained his
146:Geological Survey of Canada
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636:2012: Douglas W. Oldenburg
431:Lapidary Journal- May 2003
352:. Chemical Geology 70: 70.
271:Canadian Geophysical Union
258:American Geophysical Union
646:
572:
492:
240:
175:
627:2009: Garth van der Kamp
541:1989: Leonard S. Collett
32:This article includes a
16:Canadian geochronologist
750:Wilson Medal recipients
624:2008: Ming-ko (Hok) Woo
606:2003: Garry K.C. Clarke
511:1981: George D. Garland
421:ISI Knowledge Krogh Bio
391:Encyclopædia Britannica
372:Encyclopædia Britannica
302:Royal Society of Canada
61:more precise citations.
760:Logan Medal recipients
559:1994: Michael J. Berry
538:1988: Ernie Kanesewich
526:1985: Harold O. Seigel
345:. Nature 366: 731–734.
594:1999: David J. Dunlop
585:1997: Chris Beaumount
508:1980: Larry W. Morley
505:1979: Roy O. Lindseth
212:University of Toronto
130:Peterborough, Ontario
725:Royal Ontario Museum
603:2002: Doug E. Smylie
600:2001: Roy D. Hyndman
597:2000: Donald M. Gray
544:1990: Gordon F. West
529:1986: Mike Rochester
514:1982: Jack A. Jacobs
485:J. Tuzo Wilson Medal
267:J. Tuzo Wilson Medal
235:zircon geochronology
207:and other minerals.
182:Carnegie Institution
106:Royal Ontario Museum
639:2013: Zoltan Hajnal
630:2010: Nigel Edwards
553:1992: R. Don Russel
549:Thomas Edvard Krogh
375:on isotopic dating.
308:Select publications
292:Geochemical Society
142:Triana Explorations
113:uranium-lead dating
90:Thomas Edvard Krogh
665:2017: John Pomeroy
653:2014: Philip Marsh
621:2007: Herb Dragert
556:1993: Alan E. Beck
517:1983: D. Ian Gough
362:Krogh, T.E. 1961.
355:Krogh, T.E. 1982.
348:Krogh, T.E. 1988.
265:1991, awarded the
246:1989, awarded the
172:in geochronology.
134:Queen's University
128:Krogh was born in
34:list of references
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674:2020: David Eaton
668:2018: Gary Jarvis
564:Charlotte E. Keen
220:He worked on the
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677:2021: Jim Buttle
671:2019: Patrick Wu
656:2015: Kelin Wang
618:2006: Alan Jones
590:Ronald M. Clowes
501:John Tuzo Wilson
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186:Washington, D.C.
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193:geochemistry
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53:Please help
45:
740:2008 deaths
735:1936 births
248:Logan Medal
117:Precambrian
110:radiometric
59:introducing
694:Categories
522:Ted Irving
487:recipients
380:References
222:Lithoprobe
67:March 2021
573:1993–2007
493:1978–1992
228:Discovery
201:Strontium
158:Geologist
124:Education
197:Rubidium
190:isotopic
104:for the
269:by the
250:by the
205:zircons
162:Cominco
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55:improve
659:2016:
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241:Honors
176:Career
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150:MSc
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