Richard J. Walker is a geo- and cosmo-chemist at the University of Maryland. He is known for isotopic studies of elements such as osmium and tungsten that tend to concentrate in the metallic portions of planetary bodies, leading to new insights to early solar system processes including the origin of the Earth and Moon. Walker was born in Baltimore, Maryland. He obtained a B.S. degree in Geology from the College of William and Mary. He completed both M.S. and Ph.D. degrees in Earth and Space Sciences from the State University of New York at Stony Brook. He did postdoctoral work at the U.S. National Bureau of Standards, the Carnegie Institution of Washington?s Department of Terrestrial Magnetism, and the U. S. Geological Survey. He became a member of the faculty at the University of Maryland in 1990. He served as Chair of the department from 2015 to 2021. He was the 1990 recipient of the Clarke Medal of the Geochemical Society, and the 2019 Hess Medalist of the American Geophysical Union. He is a fellow of the American Geophysical Union, the European Association for Geochemistry and the Geochemical Society. He is a member of both the National Academy of Sciences and the American Academy of Arts and Sciences.

Research Interests

Professor Walker utilizes radiogenic isotopes and trace elements to conduct research in several areas of geo- and cosmo-chemistry including the formation and crystallization histories of early solar system planetesimals, the accretional and differentiation histories of the Earth, Moon and Mars, and the chemical evolution of Earth's mantle and crust. He and his group specialize in the study of so called siderophile elements that tend to concentrate in metal phases, including planetary cores. He was a pioneer in the application of the long-lived Re-Os, and the short-lived Hf-W isotopic systems to high temperature geochemistry. He has worked extensively with iron meteorites, many of which originated from asteroidal cores.

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Primary Section

Section 15: Geology

Secondary Section

Section 16: Geophysics