Guiana Shield
| Guiana Shield | |
| Region | |
 the Guiana Shield
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| Region | South America |
|---|---|
| Location | northeastern South America |
| - coordinates | 5°08′36″N 60°45′45″W / 5.14333°N 60.76250°WCoordinates: 5°08′36″N 60°45′45″W / 5.14333°N 60.76250°W |
The Guiana Shield 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. 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 spectacular waterfalls such as Angel Falls, Kaieteur Falls and Kuquenan Falls.
The Guiana Shield underlies Venezuela, Guyana (previously British Guiana), Suriname (previously Dutch Guiana) and French Guiana (or Guyane), as well as parts of Colombia, and Brazil. The rocks of the Guiana Shield consist of metasediments and metavolcanics (greenstones) overlain by quasi-horizontal layers of sandstones, quartzites, shales and conglomerates intruded by sills of younger mafic intrusives such as gabbros.
There are three upland areas of the Guiana Shield:
The north-central part of the Guiana Highlands is dominated by high flat-topped peaks called tepuis, of the Roraima supergroup and Quasi-Roraima formation, and the rounded granite peaks of the Parguaza and Imataca complexes to the north and southwestern edges of the area. The highest point in the shield is Pico da Neblina in Brazil at 2,995 metres (9,826 ft). Pico da Neblina is the highest summit of the larger Neblina massif, a highly eroded sandstone plateau that straddles the Venezuela-Brazil border and that has lost the typical tabletop shape of the other tepuis in the region.
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