G. Brent Dalrymple (born May 9, 1937 ) is an American geologist , author of The Age of the Earth and Ancient Earth, Ancient Skies, and National Medal of Science winner.[1]
He was born in Alhambra, California . After receiving a Ph.D. from University of California, Berkeley , Dalrymple went to work at the U.S. Geological Survey (USGS) in Menlo Park, California . In 1994 he left the USGS to accept a position at Oregon State University , where he served on the faculty until retiring in 2001. He is a member of the National Academy of Sciences .
In 2003, Dalrymple was awarded the National Medal of Science .[2] He was presented with the Medal at a ceremony in 2005.[3]
I usually hear 'on the faculty'.
What is your question exactly? Emotion: smile
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on or in, which usage is proper there?
NL888where he served on the faculty untill.. .
It's referencing the faculty as a physical space, a geographical location.

Both in and on are possible, and which one is used depends on the context and/or the intended meaning.
If in is used, does it refer to mentally in the rank of the faculty?
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 Clive's reply was promoted to an answer.