A broadly trained geologist and avid naturalist, Dr. Brian Yellen is thrilled to serve as the Massachusetts State Geologist. Yellen specializes in earth surface processes, coastal processes, and hydrology. He brings varied professional experience to the Massachusetts Geological Survey, including work in the private sector groundwater cleanup industry, teaching high school physical science, and academic research. Since 2012, he has taught professional development workshops to licensed environmental consultants, teaching skills in hydrogeology and geomorphology. Research highlights from Yellen’s recent work include assessments of dam removals and sediment transport, coastal change and blue carbon, and fluvial erosion due to extreme floods. Climate change adaptation is a common theme in Yellen’s work, and reflects his past role directing a graduate fellowship program focused on developing stakeholder engagement and collaboration skills surrounding climate adaptation. Yellen received his bachelors from Brown University, a masters in education from the University of Hawaii Manoa, and his Ph.D. in geology from the University of Massachusetts Amherst. He has been a faculty member and graduate student advisor in the department of Earth, Geographic, and Climate Sciences at UMass Amherst since 2017.
Stephen B. Mabee Emeritus State Geologist (Retired)
Serving as State Geologist from 2002 to 2024, Dr. Stephen B. Mabee received his B.S. degree in Geology from Tufts University in 1974 and an M.S. degree in Geology from the University of Colorado in 1978. He worked for nearly 10 years in the private sector as an environmental consultant working for R.V. Lord and Associates in Boulder, Colorado and Sasaki Associates, Inc. in Watertown, MA where he was a senior associate and project manager. He worked on major design and construction projects across the U.S. He received his Ph.D. in Geology from the University of Massachusetts Amherst in 1992 with a focus on hydrogeology, geochemistry, geophysics and structural geology. He was a visiting assistant professor at Amherst College from 1992 to 1995 teaching hydrogeology and environmental geology and an introductory environmental topics course. He joined the faculty in the Department of Geosciences at the University of Massachusetts in 1995. His research interests and outreach activities include: 1) groundwater resource evaluation in bedrock; 2) application of geophysical techniques to environmental problems; 3) hydrogeological education; and, 4) water resources in ancient cultures. He was appointed State Geologist on September 1, 2002 and retired in February, 2024, but continues to serve as emeritus faculty in the Department of Geosciences.
The MA Geological Survey
Department of Geosciences
269 Morrill Science Center
University of Massachusetts
611 North Pleasant Street
Amherst, MA 01003-9297