- Jan. 1997 Assistant Professor, University of Maryland at College Park
1995-1997 Research Associate, Harvard University
1993-1995 Research Associate and Mass Spectrometry Facility Manager, Harvard
1990-1993 Post-doctoral Fellow, Harvard University, supervisors Profs.
A.H. Knoll and S.B. Jacobsen
1983-1990 Research Assistant, Indiana University, Biogeochemical Laboratories,
supervisors Profs. J. M. Hayes and C. Klein
1981 Research Assistant, Louisiana State University, supervisor Prof. J.