Robert P. Sharp, 92; Expert on Surfaces of Earth and Mars

Robert P. Sharp, 92, a geologist and leading authority on the surfaces of the Earth and Mars and former head of the geological sciences division at Caltech, died Tuesday at his home in Santa Barbara, the school announced Wednesday. The cause of death was not reported.

Sharp, a native of Oxnard, arrived at Caltech as an undergraduate in 1930. A star quarterback in high school, he played for Caltech when the school fielded a football team.

After earning his bachelor’s and master’s degrees at Caltech, Sharp went to Harvard University for a doctorate in geology. He taught at the University of Illinois before leaving academia to serve in the Army Air Forces during World War II. He attained the rank of captain while working as an analyst in the Arctic, Desert and Tropical Information Center.

Sharp joined the University of Minnesota faculty after the war, then returned to Caltech as a professor in 1947. He was head of geological sciences from 1952 to 1968. He retired in 1979, but retained an active schedule, leading field trips to areas of geological interest.