Santa Susana Formation Explained

Santa Susana Formation
Type:	Formation
Age:	Late Paleocene-Early Eocene
Period:	Eocene
Prilithology:	Shale
Otherlithology:	Sandstone, conglomerate
Namedfor:	Santa Susana, California
Region:	Los Angeles County and Ventura County, California
Underlies:	Meganos Formation
Overlies:	Martinez Formation
Thickness:	1000-
Extent:	Simi Hills, Santa Susana Mountains

The Santa Susana Formation is a Paleogene period geologic formation in the Simi Hills and western Santa Susana Mountains of southern California.^{[1] [2] [3]}

The formation consists largely of light-gray shale and some fine-grained shaly sandstone, with a lens of heavy conglomerates in the lower part.^{[1] [4]} Small beds of limestone are also present.^[5] It is from 1000feet-1500feetft (-ft) thick.^{[1] [4]}

Fossil content

The Santa Susana Formation preserves fossils from the Late Paleocene to Early Eocene epochs in the Paleogene period of the Cenozoic Era.^{[4] [6]} Fossilized fauna in the Santa Susana Formation is entirely different from that of underlying Martinez Formation, and has very little in common with that of the overlying Meganos Formation.^{[1] [3] [7]}

See also

• • List of fossiliferous stratigraphic units in California
  • Paleontology in California

Notes and References

1. http://ngmdb.usgs.gov/Geolex/UnitRefs/SantaSusanaRefs_11777.html USGS.gov: Geolex - Santa Susana Formation
2. http://ngmdb.usgs.gov/Prodesc/proddesc_88561.htm "A summary of work in progress on the Tertiary and Quaternary of western North America"
3. http://ngmdb.usgs.gov/Prodesc/proddesc_92186.htm "A contribution to the paleontology of the Martinez Eocene of California"
4. http://pubs.usgs.gov/of/1995/0829/report.pdf USGS.gov: "Preliminary geologic map of the Santa Susana quadrangle, Southern California"
5. Campbell, R.H., Wills, C.J., Irvine, P.J., and Swanson, B.J., 2016. Preliminary geologic map of the Los Angeles 30' x 60' quadrangle, California.Version 2.1, California Geological Survey, Preliminary Geologic Maps PGM-13-06 https://ngmdb.usgs.gov/mapview/?center=-118.371,34.313&zoom=10
6. Web site: Fossilworks: Gateway to the Paleobiology Database. ((Various Contributors to the Paleobiology Database)). 17 December 2021.
7. http://ngmdb.usgs.gov/Prodesc/proddesc_89767.htm "Checklist of California Tertiary marine Mollusca"