Sydney Procter Clark, Jr. passed away quietly on Dec. 24, 2016. He was born in Philadelphia, PA to Sydney Procter Clark, Sr. and Isabella Mumford Clark. He is survived by his wife of 54 years Elizabeth ('Dibbie') Frey Clark. In 1947, he graduated from Pomfret School and later received both his B.S. ('51) and Ph.D. ('55) in Geology from Harvard University. After a brief period at the Carnegie Geophysical Laboratory in Washington, DC, he became the Sidney J. Weinberg Professor of Geophysics at Yale University for 25 years. Syd was one of the pioneers of geophysics, known for his early work on mineral physical chemistry and the uplift rates of the Alps using heat flow and radioactive geochronology, as well as theories of planetary formation. This later work led to lunar experiments conducted during three Apollo missions. Syd authored numerous papers and books. He was the recipient of a Fulbright Award to conduct research in Australia and served as a Trustee for Pomfret School. He enjoyed traveling with his wife Dibbie, gardening, 'Kailua' Bermuda, the theater, trains, and the company of family and friends. Above all, Syd was a loving husband, father and grandfather. In addition to his wife Dibbie, Syd is survived by children Edward Clark of Canton, Jordan Clark (Dorothy Pak) of Goleta CA, Elizabeth ('Lisa') Clark of Brookfield, and Christina Clark (Michael O'Hare) of New York, NY; and grandchildren Emily, Rachel, Isabel, Rebecca, Margaret, Logan, Daniel, Malachy, and Lleyton, to whom he read The Night Before Christmas every Christmas Eve. Services will be held on Friday, Jan. 6 at 11:30 am at the First Church of Christ, Meeting House Lane, Woodbridge. In lieu of flowers, donations can be made to the Clark Chapel Endowment Fund at Pomfret School (http://www.pomfretschool.org/page/giving-/capitalendowment-giving). Arrangements in care of BEECHER & BENNETT FUNERAL HOME, 2300 Whitney Ave., Hamden.