Photo by Rensselaer/Kris Qua

A plaque honoring Ebenezer Emmons, Class of 1826, a renowned geologist and the Institute’s first professor of geology, was unveiled during a ceremony that took place on the Rensselaer campus in April. 

During his lifetime, Emmons — who studied the natural sciences under Rensselaer co-founder and well-known geologist Amos Eaton, and who graduated in Rensselaer’s first class – made a number of highly significant and influential contributions to the modern understanding of the geology of upstate New York.

Working as the chief geologist for the northern New York State Geological District, Emmons was responsible for naming the Adirondacks and the Taconic Mountains. He also organized and led the first recorded ascent of Mt. Marcy in 1837, naming the peak for New York State Governor William Learned Marcy. His extensive writings on the Adirondacks led to increased public awareness of the region.

While working with the New York State Geological Survey, Emmons recognized that the rocks that formed the Taconic Mountains and that were found in the easternmost part of New York state and western Massachusetts were fundamentally different and much older than the rocks to their west. He named them the “Taconic sequence.” 

On the Rensselaer campus, the aged rocks can still be seen today. The plaque honoring Emmons is appropriately placed atop them, on the thrust fault that runs between the Russell Sage dining hall and the pedestrian footbridge.

“We now know that the rocks on which we stand began their geological life over 100 kilometers to the east – probably somewhere around Springfield, Mass., and were carried to their present resting place along a major thrust fault,” said Frank Spear, chair of earth and environmental sciences, during the ceremony. “That thrust fault runs just about through the end zone of [our] football field. It is by far the largest such fault in the northeastern United States. Appropriately, it is called Emmons’ line.”

“Thanks to the untiring work of Gerald Friedman, [professor emeritus of earth and environmental sciences], who spearheaded this effort and has written numerous papers about the history of geology at Rensselaer, Ebenezer Emmons is [finally] getting credit for his contributions.”

Active in the scientific community, Emmons hosted the first meeting of the American Association of Geologists in his Albany home in 1838. The organization later became the American Association for the Advancement of Science (AAAS).

Emmons served as a junior professor of mineralogy and geology at Rensselaer from 1830 – 1839.

Published June 30, 2006