Ph.D. Geology, University of Colorado, 1969
M.S. Geology, University of Minnesota, 1964
B.A. Geology, University of Wisconsin, 1960
Plant-macrofossil analysis, Quaternary environments of the Midwest and Rocky Mountains
- Professor Emeritus, 2000-present
- Chairman, Department of Geology, University of Iowa, 1992-1995
- Professor of Biology, University of Iowa, 1992-present (Joint appointment)
- Professor of Botany, University of Iowa, 1988-1992 (Joint appointment)
- Professor of Geology, University of Iowa, 1982-present.
- Associate Professor of Geology, University of Iowa, 1975-1981.
- Assistant Professor of Geology, University of Iowa, 1970-74.
- Geologist (intermittent), U.S.G.S., 1980-1985.
- Geologist (intermittent, temporary), U.S.G.S., 1972-79.
- Project Associate in Meteorology, University of Wisconsin, 1969-70.
- Teaching Associate, Geology Dept. University of Colorado, 1967-69.
- Geological Society of America (Fellow)
- American Quaternary Association (Councilor, 2000-2004)
- Editorial Board, Plant Ecology, 2001
- Geological Society of Iowa
- Iowa Academy of Science (Fellow)