Dr. Stewart received his B.S. in Geology from Brown University and Ph.D. in Geochemistry from UCLA, with a focus on magma chamber processes. After postdoctoral work on meteorite petrogenesis at Caltech and soil cation cycling at UC Riverside, he joined the Pitt faculty in 1994. Since that time he has studied geologic and environmental processes using radiogenic and metal isotope systems as tracers. Dr. Stewart served as Department Chair from 2005 to 2008.