Research Associates

Research Associates

Yuri Amelin
Researcher Associate
Ph.D., Leningrad State University (1983)

Geochronology, cosmochronology, and isotope geochemistry. Formation and early evolution of the solar system. Early evolution of the Earth's crust and mantle. Precise calibration of the geological timescale. Decay constants, migration and partitioning of elements, natural and instrumental fractionation of isotopes, and other fundamental parameters and processes relevant to radiogenic isotope geochemistry. New techniques, applications, and instrumentation aimed at achieving the highest possible precision and accuracy in isotopic dating, isotopic analysis, and analytical geochemistry. Disequilibrium in U and Th decay series, and its application as a geochronometer and isotopic tracer. Quaternary geochronology. Radiation effects in solids.

Ian MacGregor
Research Associate
Ph.D., Princeton University (1964)

Now retired having worked as Professor in Geology Department, UC Davis and Division Director, Earth Sciences, National Science Foundation.  Research interests focus on understanding mineralogy, petrology and geochemistry of upper mantle using field and experimental approaches.  Current research includes development of geothermometers and geobarometers for mantle samples in the spinel peridotite stability field.   Now work in science education as science consultant to National Science Resources Center, Smithsonian Institution on development of K -12 science curricula.

Roy J. Shlemon
Research Associate; Senior Fellow of Mathematical and Physical Sciences
Ph.D., University of California, Berkeley (1967) 

Applications of Quaternary geology, geomorphology and soil stratigraphy to engineering practice. Fault-activity assessments (paleoseismicity/neotectonics); natural and anthropic influences on slope stability; paleochannels and contaminant pathways. Also involved in forensic geology as a Consultant, Expert Witness, Neutral Referee and Mediator. Provide and interpret geoscience information for government agencies, attorneys, private engineering and environmental firms, land conservation and development organizations. GEL 136: Ecogeomorphology of Rivers and Streams

Robert A. Wiebe
Research Associate
Ph.D. Stanford University (1966) 

Igneous petrology. Research focuses on the growth of granitic, mafic and composite intrusive bodies with an emphasis on understanding the plutonic record of magma chamber processes including interactions between coexisting mafic and granitic magmas. Recent projects include studies in coastal Maine, the Sierra Nevada, and the Lachlan Fold Belt in Australia.