Guiana Shield | |
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![]() Political map of the Guiana Shield | |
Coordinates: 5°08′36″N 60°45′45″W / 5.14333°N 60.76250°W | |
Region | South America |
The Guiana Shield[1] (French: Plateau des Guyanes, Bouclier guyanais; Dutch: Hoogland van Guyana, Guianaschild; Portuguese: Planalto das Guianas, Escudo das Guianas; Spanish: Escudo guayanés) is one of the three cratons of the South American Plate. It is a 1.7 billion-year-old Precambrian geological formation in northeast South America that forms a portion of the northern coast.[2] The higher elevations on the shield are called the Guiana Highlands, which is where the table-like mountains called tepuis are found. The Guiana Highlands are also the source of some of the world's most well-known waterfalls such as Angel Falls, Kaieteur Falls and Cuquenan Falls.
The Guiana Shield underlies Guyana (previously British Guiana), Suriname (previously Dutch Guiana), and French Guiana (or Guyane), much of southern Venezuela, as well as parts of Colombia and Brazil. The rocks of the Guiana Shield consist of metasediments and metavolcanics (greenstones) overlain by sub-horizontal layers of sandstones, quartzites, shales and conglomerates intruded by sills of younger mafic intrusives such as gabbros.[3]