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Coranzulí (caldera)
Coranzuli is a back-arc caldera in the Andes, related to the Altiplano-Puna volcanic complex. It formed along the Lipez geological lineament about 6.6 million years ago. Volcanic ash samples found in the Coastal Cordillera of Chile may come from this volcano. The Rachaite () stratovolcano is located close to the caldera. The formation of this caldera has been influenced by a number of local fault systems, the Coyaguayama and Rachaite lineaments. Marine sediments of Ordovician age with some later volcanic intrusions form the basement together with Cretaceous-Eocene sediments. Three cycles of volcanic activity preceding the Coranzuli ignimbrite have been identified. The Coranzuli system is part of a Late Miocene volcanic episode that also includes Aguas Calientes, Cerro Panizos and the Toconquis ignimbrite of Galan. The Morro Grande Formation may have originated by volcanic activity in the area of Cerro Coranzuli. 6.8 to 6.4 million years ago, this caldera erupted the Coranzul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back-arc
A back-arc basin is a type of geologic basin, found at some convergent plate boundaries. Presently all back-arc basins are submarine features associated with island arcs and subduction zones, with many found in the western Pacific Ocean. Most of them result from tensional forces, caused by a process known as oceanic trench rollback, where a subduction zone moves towards the subducting plate. Back-arc basins were initially an unexpected phenomenon in plate tectonics, as convergent boundaries were expected to universally be zones of compression. However, in 1970, Dan Karig published a model of back-arc basins consistent with plate tectonics. Structural characteristics Back-arc basins are typically very long and relatively narrow, often thousands of kilometers long while only being a few hundred kilometers wide at most. For back-arc extension to form, a subduction zone is required, but not all subduction zones have a back-arc extension feature. Back-arc basins are found in area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morro Grande Formation
Morro (Spanish and Portuguese for "hill") may refer to: Buildings *El Morro mine, Atacama, Chile *El Morro National Monument, New Mexico * Morro del Tulcán, pyramid in Popayán, Cauca *Morro Castle (Havana), fortress in Havana, Cuba * El Morro de San Felipe, fortress in Puerto Plata, Dominican Republic *Castillo San Felipe del Morro, a citadel in San Juan, Puerto Rico Geology *Morro Rock, a volcanic plug located just offshore from Morro Bay, California * Isla El Morro, island near Acapulco, Mexico *Isla El Morro, small island near Taboga Island, Panama Places ;Brazil * Morro Agudo, a municipality in the state of São Paulo * Morro Agudo de Goiás, a municipality in the state of Goiás * Morro Cabeça no Tempo, a municipality in the state of Piauí * Morro da Fumaça, a municipality in the state of Santa Catarina * Morro do Chapéu, a municipality in the state of Bahia * Morro do Chapéu do Piauí, a municipality in the state of Piauí * Morro da Garça, a municipality in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes Of Jujuy Province
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
