Matilija Sandstone

Matilija Sandstone
Stratigraphic range: Eocene
Outcrop of the Matilija Sandstone in the Santa Ynez Mountains, California.
Typesedimentary
UnderliesCozy Dell Shale
OverliesJuncal Formation
Thickness0–2,500 ft (0–762 m)[1]
Lithology
PrimarySandstone
Location
RegionCoastal southern California
Country United States
Type section
Named byT. Dibblee[2]

The Matilija Sandstone (/məˈtɪləhə/) is a sedimentary geologic unit of Eocene epoch in the Paleogene Period, found in Santa Barbara and Ventura Counties in Southern California.

It consists of thick layers of sandstone, made up of grains of feldspar and quartz from a granitic source rock, interbedded with thin layers of siltstone and shale. Hard, massive, and exceptionally resistant to weathering, it forms the high rocky summits of the Santa Ynez Mountain range north of Santa Barbara, eastward into Ventura County.[2]: 25–26 

  1. ^ Minor, S.A., Kellogg, K.S., Stanley, R.G., Gurrola, L.D., Keller, E.A., and Brandt, T.R., 2009, Geologic Map of the Santa Barbara Coastal Plain Area, Santa Barbara County, California: U.S. Geological Survey Scientific Investigations Map 3001, scale 1:25,000, 1 sheet, pamphlet, 38 p.
  2. ^ a b Dibblee, Thomas. Geology of the central Santa Ynez Mountains, Santa Barbara County, California. Bulletin 186, California Division of Mines and Geology. San Francisco, 1966. 99 p.