Santa Juana Formation
| Santa Juana Formation | |
|---|---|
| Stratigraphic range: Carnian | |
| Type | Geological formation |
| Sub-units | Talcamávida-Gomero Member Unihue Member Quilacoya Member |
| Overlies | Coastal Batholith of central Chile |
| Thickness | Unknown |
| Lithology | |
| Primary | conglomerate, sandstone, siltstone, |
| Other | Arkosic sandstone, mudstone, volcanic rock, anthracite |
| Location | |
| Coordinates | 37°12′S 73°00′W / 37.2°S 73.0°W |
| Approximate paleocoordinates | 53°48′S 39°54′W / 53.8°S 39.9°W |
| Region | Bío Bío Region |
| Country |  Chile |
| Type section | |
| Named for | Santa Juana |
| Named by | Ferraris |
| Year defined | 1981 |
  Santa Juana Formation (Chile) | |
Santa Juana Formation a sedimentary rock formation near Santa Juana in the lower course of Biobío River in south-central Chile. Lithologies range from conglomerate sandstone, arkosic sandstone, siltstone and mudstone.[1]
Description
The sediments that consolidate into the rocks of the formation deposited in alluvial, fluvial, lacustrine and playa lake environment. Overall the formation is rich in plant fossils.[1]
The formation was deposited over the rocks of the Coastal Batholith of central Chile in a sedimentary basin that formed along the Gastre Fault. It has been posited that the basin developed as a rift during the early break-up of Gondwana in the Triassic.[1]
See also
- Chañares Formation, fossiliferous formation of the Ischigualasto-Villa Unión Basin, Argentina
- Candelária Formation, contemporaneous fossiliferous formation of the Paraná Basin, Brazil
- Molteno Formation, contemporaneous fossiliferous formation of Lesotho and South Africa
- Pebbly Arkose Formation, contemporaneous fossiliferous formation of Botswana, Zambia and Zimbabwe
- Denmark Hill Insect Bed, contemporaneous fossiliferous unit of Queensland, Australia
- Madygen Formation, contemporaneous Lagerstätte of Kyrgyzstan
References
- ^ a b c Nielsen, Sven N. (2005). "The Triassic Santa Juana Formation at the lower Biobío River, south central Chile". Journal of South American Earth Sciences. 19: 547–562. doi:10.1016/j.jsames.2005.06.002.
