Cozy Dell Shale

Cozy Dell Shale
Stratigraphic range: Eocene
Talus slope on an outcrop of Cozy Dell Shale, Santa Ynez Mountains, California.
Typesedimentary
UnderliesColdwater Sandstone
OverliesMatilija Sandstone
Thickness350 to 4,000 feet (107 to 1,219 m)
Lithology
Primaryshale
Otherminor sandstone beds, calcareous nodules
Location
RegionCoastal southern California
CountryUnited States
Type section
Named forCozy Dell Canyon, Ventura County
Named byKerr and Schenck (1928)

The Cozy Dell Shale is a geologic formation of middle Eocene age that crops out in the Santa Ynez Mountains and Topatopa Mountains of California, extending from north of Fillmore in Ventura County westward to near Point Arguello, north of Santa Barbara. Because the Cozy Dell easily weathers to a clay-rich soil, it crops out infrequently and generally forms dense stands of chaparral in saddles between peaks and ridges of the more resistant Matilija and Coldwater formations.