About the Authors
It has been said that science is a history of superseded theories. New theories and innovative approaches to research and teaching are mostly the work of the next generation of scientist-authors. We are fortunate that two accomplished and well-known geologists have agreed to ‘supersede’ us in future editions of Understanding Earth. They share the philosophy and idealism represented in our book, as well as our commitment to quality and currency, and they value the good will our book has built up over the years.
Introducing John Grotzinger and Thomas H. Jordan
John P. Grotzinger is a field geologist interested in the evolution of Earth’s surficial environments and biosphere. His research addresses the chemical development of the early oceans and atmosphere, the environmental context of early animal evolution, and the geologic factors that regulate sedimentary basins. He has contributed to the basic geologic framework of a number of sedimentary basins and orogenic belts in northwest Canada, northern Siberia, southern Africa, and the western United States. These field mapping studies are the starting point for more topical laboratory-based studies involving geochemical, paleontological, and geochronological techniques. He received a B.Sc. in Geoscience from Hobart College in 1979, an M.Sc. in Geology from the University of Montana in 1981, and a Ph.D. in Geology from Virginia Tech in 1985. He spent 3 years as a Research Scientist at the Lamont-Doherty Geological Observatory before joining the MIT faculty in 1988. From 1979 to 1990 he was engaged in regional mapping for the Geological Survey of Canada. In 1998 he was named the Waldemar Lindgren Distinguished Scholar at MIT and in 2000 became the Robert R. Shrock Professor of Earth and Planetary Sciences. In 1998 he was appointed Director of MIT’s Earth Resources Laboratory. He received the Presidential Young Investigator Award of the National Science Foundation in 1990, the Donath Medal of the Geological Society of America in 1992, and the Henno Martin Medal of the Geological Society of Namibia in 2001. He is a member of the American Academy of Arts and Sciences and the National Academy of Sciences.
Thomas H. Jordan is a geophysicist interested in the composition, dynamics, and evolution of the solid Earth. His research has concerned the nature of plate-tectonic return flow, the formation of a thickened tectosphere beneath the ancient continental cratons, and the question of mantle stratification. He has developed a number of seismological techniques for elucidating structural features in the Earth’s interior that bear on these and other geodynamic problems. He has also worked on modeling plate motions, measuring neotectonic deformations in plate-boundary zones, quantifying various aspects of seafloor morphology, and characterizing large earthquakes. He received his Ph.D. in geophysics and applied mathematics at the California Institute of Technology in 1972 and taught at Princeton University and the Scripps Institution of Oceanography before joining the MIT faculty as the Robert R. Shrock Professor of Earth and Planetary Sciences in 1984. He served as the head of MIT’s Department of Earth, Atmospheric and Planetary Sciences for the decade 1988–1998. He recently moved from MIT to the University of Southern California, where he is the W. M. Keck Professor of Geological Sciences and Director of the Southern California Earthquake Center. He received the James B. Macelwane Medal of the American Geophysical Union in 1983 and the George P. Woollard Award of the Geological Society of America in 1998. He is a member of the American Academy of Arts and Sciences, the National Academy of Sciences, and the American Philosophical Society.
