The Repetto Formation is a
Pliocene epoch
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58[unit
Unit may refer to:
Arts and entertainment
* UNIT, a fictional military organization in the science fiction television series ''Doctor Who''
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* ''Unit'' (a ...](_blank)
in the greater
Los Angeles Basin
The Los Angeles Basin is a sedimentary Structural basin, basin located in Southern California, in a region known as the Peninsular Ranges. The basin is also connected to an wikt:anomalous, anomalous group of east-west trending chains of mountai ...
composed primarily of
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates ...
and
conglomerate.
Geology
The unit records deposition of a
submarine fan environment at lower
bathyal
The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The bathypelagi ...
depths, and is recognized as a productive
petroleum reservoir.
[Repetto Formation, at Bureau of Economic Geology, University of Texas, Austin](_blank)
[Blake, Gregg H. 1991. "Review of the Neogene biostratigraphy and stratigraphy of the Los Angeles Basin and implications for basin evolution," In: Biddle, Kevin T. (ed), "Active Margin Basins", AAPG Memoir 52, 319pp.]
The formation is overlain by the
Pico Formation
The Pico Formation is a Pliocene epoch stratigraphic unit and geologic formation in the greater Los Angeles Basin, the Santa Monica Mountains, and the Santa Susana Mountains, in Los Angeles County of Southern California.
Geology
It was formed du ...
, both of the
Neogene period
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ...
.
Classification
The Repetto Formation is equivalent in age to the
Fernando Formation
The Fernando Formation is a Plio-Pleistocene marine mudstone, siltstone and sandstone formation in the greater Los Angeles Basin, Ventura Basin, and Santa Monica Mountains, in Los Angeles County of Southern California.
Geology
Outcrops of the ...
; some researchers consider it (as well as the overlying
Pico Formation
The Pico Formation is a Pliocene epoch stratigraphic unit and geologic formation in the greater Los Angeles Basin, the Santa Monica Mountains, and the Santa Susana Mountains, in Los Angeles County of Southern California.
Geology
It was formed du ...
) to be a junior synonym based on benthic
foraminifera
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular ectoplasm for catching food and other uses; and commonly ...
stages.
Other researchers maintain that the Repetto and Pico Formations are distinct stratigraphic units, and that the use of the name "Fernando Formation" should be stopped due to several issues with stratigraphic correlation and access to the type section.
[Blake, Gregg H. 1991. "Review of the Neogene biostratigraphy and stratigraphy of the Los Angeles Basin and implications for basin evolution," In: Biddle, Kevin T. (ed), "Active Margin Basins", AAPG Memoir 52, 319pp.]
See also
*
*
List of fossiliferous stratigraphic units in California
This article contains a list of fossil-bearing stratigraphic units in the state of California, California, U.S.
Sites
See also
* Paleontology in California
References
*
{{DEFAULTSORT:Fossiliferous stratigraphic units in California
F ...
References
Pliocene California
Geology of Los Angeles County, California
Geologic formations of California
Petroleum in California
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