James Farquhar a Professor in the Department of Geology and a member of the Earth System Science Interdisciplinary Center (ESSIC) at the University of Maryland. Farquhar studied Geology as an undergraduate at Washington and Lee University, as a Masters student at the University of Chicago working with Steve Wickham, and as a Ph.D. student at the University of Alberta working with Tom Chacko. Farquhar was a postdoctoral fellow at the Geophysical Laboratory, Carnegie Institution for Science working with Doug Rumble from 1995 to 1997. From 1997 to 2001, Farquhar was an NSF postdoctoral fellow in the Chemistry Department at UCSD, working with Mark Thiemens. Farquhar joined the faculty at the University of Maryland, where he has worked since 2001. Farquhar has spent time as a visiting researcher/professor at the Biological Institute, University of Southern Denmark, the MPI for Marine Microbiology, Bremen, Germany, the Hanse WissenschaftsKolleg, Delmenhorst, Germany, the Institut de Physique du Globe de Paris, Paris, France, the Centre for Microscopy Characterization and Analysis at the University of Western Australia, and the Laboratoire Magmas et Volcans – Clermont Ferrand.

Research Interests

James Farquhar's research has focused primarily on sulfur isotope geochemistry in a variety of terrestrial and extraterrestrial systems with some work on oxygen isotope geochemistry. Work by Farquhar and his collaborators with sulfur spans the ancient to the modern and extends from the atmosphere to the oceans and solid Earth. Farquhar and coworkers are best known for the discovery and interpretation of mass independent sulfur isotope signatures in samples from the early Earth that trace the evolution of oxygen and chemistry in the early atmosphere. Similar signatures for Mars tell of different conditions and reflect different reactions. On both planets, they provide tracers that track sulfur from surface reservoirs into other planetary reservoirs. Farquhar and coworkers have also used sulfur isotopes to trace metabolic and biogeochemical transformations for inorganic and organic sulfur compounds using laboratory experiments and ab initio approaches. Work in the not-too-distant future will shift to studies of atmospheric gases with a focus on regional and continental methane in modern systems with the establishment of the University of Maryland high mass resolution mass spectrometry facility.

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Primary Section

Section 15: Geology