Lompoc, city, Santa Barbara County, southwestern California, in the fertile Lompoc Valley; founded in 1874, incorporated 1888. It is a major center of flower-seed production and diatomaceous-earth (diatomite) mining; petroleum also is produced. Vandenberg Air Force Base and the restored La Purisima Mission (1787) are nearby. The city's name is derived from a Chumash term perhaps meaning “shell mound.” Population 26,267 (1980); 37,649 (1990); 41,103 (2000).
