Brian Ross Weitz (March 26, 1979), also known by his stage name Geologist, is a musician best known as a member of the experimental pop group Animal Collective. He provides electronic sound manipulations and samples for the band.
Weitz grew up in Philadelphia and Baltimore and lives in Washington, DC. His nickname comes from a friend mistaking his major in college, as well as the headlamp he wears in order to see his electronic equipment during live shows.