The Catalina Schist is a

metamorphic rock Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causin ...

complex primarily exposed on Santa Catalina Island of the

Channel Islands of California The Channel Islands () are an eight-island archipelago located within the Southern California Bight in the Pacific Ocean, off the coast of California. The four Northern Channel Islands are part of the Transverse Ranges geologic province, and ...

. It formed during the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

Period of the

Mesozoic Era The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising ...

Geology

The Catalina Schist is broadly correlated with the

Franciscan Complex The Franciscan Complex or Franciscan Assemblage is a geologic term for a late Mesozoic terrane of heterogeneous rocks found throughout the California Coast Ranges, and particularly on the San Francisco Peninsula. It was named by geologist Andrew ...

, a similar metamorphic complex formed along the California margin.Rowland, Stephan M., ''Geology of Santa Catalina Island,'' California Geology, 1984 Both of these units record high-pressure/low-temperature metamorphism associated with the

subduction Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the ...

of the

Farallon plate The Farallon Plate was an ancient oceanic plate. It formed one of the three main plates of Panthalassa, alongside the Phoenix Plate and Izanagi Plate, which were connected by a triple junction. The Farallon Plate began subducting under the west ...

beneath North America during the

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...

Era. The Catalina Schist is differentiated from the Franciscan primarily in the style of

mélange In geology, a mélange is a large-scale breccia, a mappable body of rock characterized by a lack of continuous bedding and the inclusion of fragments of rock of all sizes, contained in a fine-grained deformed matrix. The mélange typically cons ...

formed during subduction. In the Los Angeles Harbor Region, Catalina Schist is associated with the

Wilmington Oil Field The Wilmington Oil Field is a prolific petroleum field in Los Angeles County in southern California in the United States. Discovered in 1932, it is the third largest oil field in the United States in terms of cumulative oil production. The field ...

References

Geologic formations of California Cretaceous System of North America Cretaceous California Schist formations Geology of Los Angeles County, California Santa Catalina Island (California) Channel Islands of California Los Angeles Harbor Region {{US-geology-stub

Geology

See also

References