Oblique aerial view of large, dogleg-shaped crack in hill behind housing development now built on 1812 La Purisima Mission site. This crack is unique in the hills south of the Santa Ynez River. Photo by A. G. Sylvester, 1971. Oblique aerial view of large, dogleg-shaped crack in hill behind housing development now built on 1812 La Purisima Mission site. This crack is unique in the hills south of the Santa Ynez River. Photo by A. G. Sylvester, 1971.