The mountainous region of Guayana rises behind the fertile, swampy and narrow coastal lowlands of northern South America on the northern edge of the Amazon basin to the Roraima-Tepui (2,810 m) and to the highest point with the Pico da Neblina (2,994 m) in the southwest. The Guiana Highlands , also known as the Guiana Shield , are about 1.7 billion years old and are a very old geological structure. It is predominantly characterized by quartzites , sandstones , arkose sandstones , conglomerates and tuffs from the Precambrian , which are penetrated by storage passages and dykes . The Roraima supergroup forms the most important lithofacial structural unit.
The area is characterized by mighty table mountains , also called tepuis , whose high plateaus have an endemic flora and fauna due to their climatic isolation from the rainforest . The highest waterfalls in the world fall from some table mountains into the tropical rainforest, such as the Salto Ángel and the Salto Kukenan . The highland ends descending on the Rio Negro and the Amazon .
The mountains are covered by savannahs and grasslands and the lowlands by the foothills of the Amazon forest , which is considered to be the largest and most biodiverse terrestrial ecosystem on earth.
In the Guayana region diamonds , gold and phosphates are mined, in the forest precious woods - often without any control and illegally - are extracted. The steppes are ideal for growing rice , cotton , cocoa , sugar cane , bananas , coconut trees , coffee , rubber .
The western part of Guyana belongs politically to Venezuela . A large part is protected by the Canaima National Park , which has been declared a World Heritage Site by UNESCO . The south of Guiana belongs to Brazil , the main part is shared by the two states Guyana (formerly British Guiana ) and Suriname (formerly Dutch Guiana ) as well as French Guiana , a French overseas department .
- Geology of Guyana: an overview. Geological overview map and brief description of the state of Guyana. Archived from the original on August 16, 2000 ; accessed on July 6, 2016 .
- Four Brazilian peaks have their altitude changed. Instituto Brasileiro de Geografia e Estatistica ( IBGE ), September 13, 2004, archived from the original on September 20, 2012 ; accessed on February 14, 2010 (English).
- Nelson Joaquim Reis: Mount Roraima, State of Roraima. The Sentinel of Macunaíma . In: In: M. Winge, C. Schobbenhaus, M. Berbert-Born et al. (Edit.): Sítios Geológicos e Paleontológicos do Brasil . DNPM / CPRM - Comissão Brasileira de Sítios Geológicos e Paleobiológicos (SIGEP) - Brasília 2002 (English)