The Cabrillo Formation is a

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

stage

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

in coastal

San Diego County San Diego County (), officially the County of San Diego, is a county in the southwest corner of the U.S. state of California, north to its border with Mexico. As of the 2020 census, the population was 3,298,634; it is the second-most populous ...

, southern

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. It is part of the

Rosario Group The Rosario Group is a Late Cretaceous group (geology), geologic group in southwestern California (United States) and northwestern Baja California (Mexico). In older literature it was named Rosario Formation. The Cretaceous aged formations of t ...

."Cabrillo National Park," Hunt, Santucci, and Kenworthy (2006); page 65. The Maastrichtian stage is of the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

Epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided b ...

, during the

Mesozoic Era The Mesozoic Era is the era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Periods. It is characterized by the dominance of archosaurian reptiles such as the dinosaurs, and of gymnosperms s ...

. The formation is found on the eastern and southwestern sides of the

Point Loma Point Loma ( Spanish: ''Punta de la Loma'', meaning "Hill Point"; Kumeyaay: ''Amat Kunyily'', meaning "Black Earth") is a seaside community in San Diego, California, United States. Geographically it is a hilly peninsula that is bordered on the ...

peninsula including in

Cabrillo National Monument Cabrillo National Monument () is a U.S. national monument at the southern tip of the Point Loma peninsula in San Diego, California. It commemorates the landing of Juan Rodríguez Cabrillo at San Diego Bay on September 28, 1542. This event mark ...

, and on

Mount Soledad Mount Soledad, also known as Soledad Mountain, is a prominent landmark in San Diego, California, United States. The mountaintop is the site of the Mount Soledad Cross. Geography The mountain lies between Interstate 5 to the east and the Pac ...

, both within the city of

San Diego San Diego ( , ) is a city on the Pacific coast of Southern California, adjacent to the Mexico–United States border. With a population of over 1.4 million, it is the List of United States cities by population, eighth-most populous city in t ...

. The Cabrillo Formation overlies the Point Loma Formation.

Fossils

A single tooth from the

cartilaginous fish Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or ''bony fish'', which have skeleto ...

Squalicorax ''Squalicorax'', commonly known as the crow shark, is a genus of extinct lamniform shark known to have lived during the Cretaceous period. The genus had a global distribution in the Late Cretaceous epoch. Multiple species within this genus are co ...

'' has been recovered from the Cabrillo Formation sediments of

.Hunt, ReBecca K., Vincent L. Santucci and Jason Kenworthy. 2006. "A preliminary inventory of fossil fish from National Park Service units." in S.G. Lucas, J.A. Spielmann, P.M. Hester, J.P. Kenworthy, and V.L. Santucci (ed.s), Fossils from Federal Lands. New Mexico Museum of Natural History and Science Bulletin 34, pp. 63–69.

Fossils

See also

References

Further reading