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The South American Plate is a major tectonic plate which includes the continent of South America as well as a sizable region of the Atlantic Ocean seabed extending eastward to the African Plate, with which it forms the southern part of the Mid-Atlantic Ridge.
23 de sept. de 2023 · The South American Plate is one of Earth’s major tectonic plates, covering a significant portion of the continent of South America and extending offshore into the Atlantic Ocean. This tectonic plate interacts with the neighboring Nazca Plate to the west, the African Plate to the east, and the Antarctic Plate to the south.
4 de ene. de 2024 · The South American Plate, despite its relatively modest size, plays a pivotal role in the intricate dance of Earth's tectonic plates. Its convergence and divergence with neighboring plates, subduction zones, and the formation of the Andes Mountains underscore its geological significance.
- Overview
- Geologic history
- The Precambrian
The geologic history of South America can be summarized in three different developmental stages, each corresponding to a major division of geologic time. The first stage encompassed Precambrian time (about 4.6 billion to 541 million years ago) and was characterized by a complex series of amalgamations and dispersals of stable blocks of protocontinental crust called cratons. The second stage coincides with the Paleozoic Era (about 541 to 252 million years ago), during which time the cratons and material accreted to them contributed to the formation first of the supercontinent Gondwana (or Gondwanaland) and then of the even larger Pangea (Pangaea). The third stage, in which the present continental structure emerged, occurred in the Mesozoic and Cenozoic eras (about the past 252 million years) and includes the breakup of Pangea and Gondwana, the opening of the South Atlantic Ocean, and the generation of the Andean cordillera.
The present tectonic framework of South America consists of three fundamental units: the ancient cratons, the relatively recent Andean ranges, and a number of basins. Five cratons—Amazonia, São Francisco, Luis Alves, Alto Paraguay, and Río de la Plata—represent the Precambrian core of South America, and (with the exception of the Alto Paraguay craton) those now appear as upwarped massifs arrayed from north to south in the immense eastern portion of the continent; a number of other Precambrian crustal blocks also were accreted along the margins of South America over geologic time. The lofty ranges and intermontane plateaus of the Andes rise along the entire western margin of the continent and represent the collision in the Cenozoic Era (about the past 66 million years) of the Pacific and South American plates brought about by the opening of the South Atlantic. Finally, vast, downwarped, sediment-filled basins are found between the cratons and along the entire eastern margin of the Andes.
The geologic history of South America can be summarized in three different developmental stages, each corresponding to a major division of geologic time. The first stage encompassed Precambrian time (about 4.6 billion to 541 million years ago) and was characterized by a complex series of amalgamations and dispersals of stable blocks of protocontinental crust called cratons. The second stage coincides with the Paleozoic Era (about 541 to 252 million years ago), during which time the cratons and material accreted to them contributed to the formation first of the supercontinent Gondwana (or Gondwanaland) and then of the even larger Pangea (Pangaea). The third stage, in which the present continental structure emerged, occurred in the Mesozoic and Cenozoic eras (about the past 252 million years) and includes the breakup of Pangea and Gondwana, the opening of the South Atlantic Ocean, and the generation of the Andean cordillera.
The present tectonic framework of South America consists of three fundamental units: the ancient cratons, the relatively recent Andean ranges, and a number of basins. Five cratons—Amazonia, São Francisco, Luis Alves, Alto Paraguay, and Río de la Plata—represent the Precambrian core of South America, and (with the exception of the Alto Paraguay craton) those now appear as upwarped massifs arrayed from north to south in the immense eastern portion of the continent; a number of other Precambrian crustal blocks also were accreted along the margins of South America over geologic time. The lofty ranges and intermontane plateaus of the Andes rise along the entire western margin of the continent and represent the collision in the Cenozoic Era (about the past 66 million years) of the Pacific and South American plates brought about by the opening of the South Atlantic. Finally, vast, downwarped, sediment-filled basins are found between the cratons and along the entire eastern margin of the Andes.
Precambrian rocks constitute the oldest rocks of the continent and are preserved in the five core cratons. Those rocks are represented by high- to low-grade metamorphosed assemblages along heavily deformed belts of plutonic (intrusive), metavolcanic (metamorphosed extrusive igneous rocks), and metasedimentary rocks. Rocks of Archean age (2.5 to 4 b...
30 de abr. de 2024 · The East Pacific Rise is located on the divergent boundary of the Pacific Plate and the Cocos Plate (west of Central America), the Nazca Plate (west of South America), and the Antarctic Plate. In addition to volcanic activity, the rise also has a number of hydrothermal vents. Transform Boundaries
29 de abr. de 2024 · These mountains are continually built up as the Nazca plate subducts under the South American plate. The Andes Mountains include the world’s highest active volcano, Nevados Ojos del Salado, which rises to 6,879 meters (over 22,500 feet) along the Chile-Argentina border .
On 9 June 1994, a magnitude-8.3 earthquake struck about 320 km northeast of La Paz, Bolivia, at a depth of 636 km. This earthquake, within the subduction zone between the Nazca Plate and the South American Plate, was one of deepest and largest subduction earthquakes recorded in South America.
