Guiana Mountains
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 .
Web links
- 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 .
Individual evidence
- ↑ 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)