The highest award of the Geological Association of Canada is presented to an individual for sustained distinguished achievement in Canadian earth science.
2026 Logan Medallist
Dr. Robert Creaser (University of Alberta)
Professor Robert Creaser, FRSC, is a Professor and former Tier I Canada Research Chair at the Department of Earth and Atmospheric Sciences, University of Alberta. He pioneered the negative thermal ionization mass spectrometry method for precise and accurate rhenium-osmium geochronology and osmium isotopic tracing. This innovative method, combined with the unique geochemical characteristics of rhenium and osmium, allowed geochronology of previously undatable geological materials and enabled novel insights into crustal and Earth surface processes.
He led the development of numerous applications for the rhenium-osmium isotope system, including: i) sulfide geochronology to constrain the timing of mineralization events, and the use of osmium isotopes to identify the source of ore-forming fluids; ii) graphite geochronology to identify key controls like supercontinent assembly on the formation of this critical mineral; iii) dating of the timing of giant hydrocarbon deposits and bitumen; iv) sedimentary geochronology using black shales, which led to improvements in geological timescale calibration and new constraints on the timing of Snowball Earth glaciations, atmosphere-ocean oxygenation, biological innovations, and supercontinents; v) use of the seawater osmium isotope tracer to identify large igneous province magmatism as the driver of climate change that led to Mesozoic oceanic anoxic events and mass extinctions; and vi) delineated the geochemical behavior of osmium in subduction zones, fingerprinting osmium transport and incorporation from subducting slabs to subduction zone magmas. This transformational work made the University of Alberta and Canada a world leader in rhenium-osmium isotope geochemistry and Earth Science research.
His distinguished scientific contributions extend well beyond his rhenium-osmium research program. He has applied high quality radioactive/radiogenic isotope data (rubidium-strontium, samarium-neodymium, lead-lead) and other geochemical approaches and modelling to mineral deposits, crustal and mantle evolution, alkaline magmatism, and granite petrogenesis. Because of his high-quality isotopic data and multidisciplinary expertise, he has co-authored many papers on other topics such as Precambrian Earth surface environments and archaeology. His rigorous training in isotope geochemistry leaves a legacy of analytical and research excellence in his trainees and mentees who became successful scientists in academia, government, and industry. These sustained distinguished achievements in Canadian Earth Science research make Professor Robert Creaser fully deserving of the Logan Medal.
The deadline for National Medal nomination forms is January 5th, 2027
Previous Award Winners
2025 Galen Halverson
2024 Dr. Sandra Barr
2023 Sandra L. Kamo
2022 Brendan Murphy
2021 Kurt Konhauser
2020 Margot McMechan
2019 Cees van Staal
2018 Barbara Sherwood Lollar
2017 Roy Hyndman
2016 Brian Jones
2015 Richard Grieve
2014 Andrew Miall
2013 George Pemberton
2012 Robert Kerrich
2011 Anthony E. Williams-Jones
2010 Christopher Barnes
2009 Noel James
2008 James M. Franklin
2007 John Clague
2006 Claude Hillaire-Marcel
2005 Ron M. Clowes
2004 Stewart Blusson
2003 Fred Longstaffe
2002 James Monger
2001 S.E. Calvert
2000 H. Gabrielse
1999 R. G. Walker
1998 D.F. Sangster
1997 E. W. Mountjoy
1996 F. C. Hawthorne
1995 J. Veizer
1994 A. J. Naldrett
1993 P. Cerny
1992 P. F. Hoffman
1991 J. R. Mackay
1990 R. L. Armstrong
1989 T. E. Krogh
1988 H. Williams
1987 D. J. Mclaren
1986 M. J. Keen
1985 R. A. Price
1984 D. W. Strangway
1983 J. O. Wheeler
1982 C. R. Stelck
1981 W. S. Fyfe
1980 G. V. Middleton
1979 R. Thorsteinsson
1978 A. Remanis
1977 A. R. Barringer
1976 R. J. W. Douglas
1975 E. Irving
1974 Y. O. Fortier
1973 C. H. Stockwell
1972 R. F. Leggett
1971 T. H. Clark
1970 D. R. Derry
1969 J. M. Harrison
1968 J. T. Wilson
1967 J. E. Gill
1966 H. C. Gunning
1965 W. A. Bell
1964 H. E. Hawley