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The Guiana Shield is one of the regions of highest biodiversity in the world, and has many endemic species. The region houses over 3000 vertebrate species: 1168 fresh water fish, 269 amphibians (54% endemics), 295 reptiles (29%), 1004 birds (7.7%), and 282 mammals (11%).
The Guiana Shield forms the northern part of the Amazonian Craton, the core of the South American continent. Most of the geology of northern Guyana consists of Palaeoproterozoic Orosirian greenstone belts (Barama-Mazaruni Supergroup) intruded by granites.
The Guiana Shield occupies the southern region of the Orinoco River and the northern region of the Amazon River, between the plains of Colombia and Venezuela and the Atlantic Ocean. It covers the whole south of Venezuela and the south of the Orinoco. It has the oldest rocks in the country. There are archaic rocks with more than 3,000 million years.
The geology of Suriname is predominantly formed by the Guyana Shield, which spans 90% of its land area. Coastal plains account for the remaining ten percent. Most rocks in Suriname date to the Precambrian.
The North Rupununi is situated on the Guiana Shield, precambrian rock with a complex geology that includes plutonic, volcanic, metamorphic and sedimentary rocks and various rifting, uplifting, sedimentation and erosion events.
The oldest rocks in Venezuela formed during the Precambrian and occupy the Guiana shield in the southern tier of the country near Guyana and Brazil, east of the El BaUl swell. In the western Guiana Shield, within the Amazonas Territory, Precambrian Roraima Formation zircon grains have been dated with uranium-lead dating and rubidium-strontium ...
Smaller cratons of Precambrian rocks south of the Amazonian Shield are the Río de la Plata Craton and the São Francisco Craton, which lies to the east. The Río Apa Craton at the Paraguay-Brazil border is considered to be likely just the southern part of the Amazonian Craton. [2] The rocks of Río Apa were deformed during the Sunsás orogeny. [3]
Guyana belongs to the Guiana Shield, a massif extending north of the Amazon, between the Andes Mountains and the Atlantic, made up of Precambrian rocks dated to between 2.7 and 3.5 billion years ago. The shield consists of several geological units: the southern peneplain, the Inini synclinorium, the central granite massifs and the northern ...