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Environmental Science: Geology

Oregon Geology

Thomas Condon (1822–1907) was an Irish Congregational minister, geologist, and paleontologist who gained recognition for his work in the U.S. state of Oregon. 

Condon was appointed the first State Geologist for Oregon in 1872. He resigned that post to become first professor of geology at the University of Oregon. Previously, he was a teacher at Pacific University in Forest Grove.

Around 1952, he traveled to Oregon by ship. As a minister at The Dalles, he became interested in the fossils he found in the area. He found fossil seashells on the Crooked River and fossil camels and other animals along the John Day River. Many of his discoveries were in the present-day John Day Fossil Beds National Monument. He corresponded with noted scientists, including Spencer Baird of the Smithsonian, Edward Cope of the Academy of Natural Sciences, Joseph Leidy, O.C. Marsh, and John C. Merriam, and provided specimens to major museums.

In The Two Islands and What Came of Them, a geology book published in 1902, Condon wrote about two widely separated regions of Oregon that contain its oldest rocks, the Klamath Mountains in the southwestern part of the state and the Blue Mountains in the northeast. The book attempted to summarize what was then known about the state's geology and to draw conclusions about its geologic past.



Willamette University

Willamette University Libraries

Mark O. Hatfield Library
900 State Street.
Salem Oregon 97301
Pacific Northwest College of Art Library
511 NW Broadway.
Portland Oregon 97209