| Cozy Dell Shale | |
|---|---|
| Stratigraphic range: Eocene | |
 Talus slope on an outcrop of Cozy Dell Shale, Santa Ynez Mountains, California. | |
| Type | sedimentary |
| Underlies | Coldwater Sandstone |
| Overlies | Matilija Sandstone |
| Thickness | 350 to 4,000 feet (107 to 1,219 m) |
| Lithology | |
| Primary | shale |
| Other | minor sandstone beds, calcareous nodules |
| Location | |
| Region | Coastal southern California |
| Country | United States |
| Type section | |
| Named for | Cozy Dell Canyon, Ventura County |
| Named by | Kerr and Schenck (1928)[1] |
The Cozy Dell Shale is a geologic formation of middle Eocene age[2] 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.[3]
- ^ Kerr, P.F.; Schenk, H.G. (1929). "Significance of the Matilija overturn". Geological Society of America Bulletin. 39 (4): 1087–1102. doi:10.1130/gsab-39-1087.
- ^ Prothero, Donald R.; Britt, Justin R. (1998). "Magnetic stratigraphy and tectonic rotation of the Middle Eocene Matilija Sandstone and Cozy Dell Shale, Ventura County, California: implications for sequence stratigraphic correlations" (PDF). Earth and Planetary Science Letters. 163 (1–4): 261–273. Bibcode:1998E&PSL.163..261P. doi:10.1016/s0012-821x(98)00192-7.
- ^ Dibblee, Thomas (1966). Geology of the central Santa Ynez Mountains, Santa Barbara County, California. San Francisco: California Division of Mines and Geology. Bulletin 186, p. 28–30.