Coldwater Sandstone

Coldwater Sandstone
Stratigraphic range: Mid-Late Eocene
Coldwater Sandstone, Santa Ynez Mountains, north of Santa Barbara, California
Type	sedimentary
Underlies	Sespe Formation
Overlies	Cozy Dell Shale
Thickness	0 to 3200 feet[1]: 16, 32
Lithology
Primary	sandstone
Other	siltstone, mudstone, occasional conglomerates
Location
Region	Southern California
Country	United States
Type section
Named for	Coldwater Canyon, tributary of the Sespe River, north of Fillmore
Named by	Watts(1896)[1]

The Coldwater Sandstone (or Coldwater Formation) is a sedimentary geologic unit of Eocene age found in Southern California, primarily in and south of the Santa Ynez Mountains of Santa Barbara County, and east into Ventura County. It consists primarily of massive arkosic sandstone with some siltstone and shale. Being exceptionally resistant to erosion, outcrops of the Coldwater form some of the most dramatic terrain on the south slope of the Santa Ynez Mountains, with immense white sculpted slabs forming peaks, hogback ridges, and sheer cliff faces.^{[1]: 32–33 [2]}