Casma Group
Casma Group Stratigraphic range: Albian-Cenomanian | |
---|---|
Type | Geological group |
Lithology | |
Primary | Limestone, marl, sandstone, conglomerate |
Other | Gypsum, tuff |
Location | |
Coordinates | 10°54′S 76°48′W / 10.9°S 76.8°WCoordinates: 10°54′S 76°48′W / 10.9°S 76.8°W |
Region | Casma Province, Ancash Region |
Country | ![]() |
Extent | |
Type section | |
Named for | Casma |
![]() ![]() Casma Group (Peru) |
The Casma Group (Spanish: Grupo Casma) is a stratigraphic group of Cretaceous (Albian to Cenomanian) sedimentary formations exposed along the coast and within the Cordillera Occidental near Casma, Peru.
Description[]
The sediments of the Casma Group reflect deposition in two distinct environments of the . Some sediments were deposited near the in an intra-cratonic sedimentary basin that was occasionally connected to the ocean. Other sediments were deposited in what was once a continental platform bounded by reefs and with anoxic pockets.[1]
Together with the Morro Solar and , the Casma Group contains clastic volcanosedimentary material derivative of the Mesozoic .[2] The folding of the Casma Group sediments is the result of the Cretaceous Mochica Phase of the Andean orogeny.[2] The group is intruded by plutons of the Coastal Batholith of Peru.[2]
The Casma Group include the following lithologies: gypsum, limestone, marl, tuff, lava flows, sandstone and conglomerate.[1]
References[]
Bibliography[]
- Contribución al estudio de las formaciones volcánicas y sedimentarias del Grupo Casma en la transversal del río Huara, Cuenca oeste-peruana. Bulletin de l'Institut français d'études andines XII. 75–89. Accessed 2019-02-21. ; ; , and . 1983.
- Mesozoic–Cenozoic Evolution of the Western Margin of South America: Case Study of the Peruvian Andes. 3. 262–310. Accessed 2019-02-21. , and . 2013.
- Geologic groups of South America
- Geologic formations of Peru
- Lower Cretaceous Series of South America
- Upper Cretaceous Series of South America
- Cretaceous Peru
- Cretaceous volcanism
- Albian Stage
- Cenomanian Stage
- Limestone formations
- Marl formations
- Sandstone formations
- Conglomerate formations
- Tuff formations
- Geography of Ancash Region
- Geography of Lima Region