What is the Guiana Highlands massif?

The Guiana Highlands is a vast plateau and low-mountain region in South America, situated between the Amazon and Orinoco rivers. Geologically, the rock underlying French Guiana forms part of this crystalline massif.12

The region is characterized by three primary terrain elements:
* Rolling hilly uplands: Generally located less than 1,000 feet (300 metres) above sea level.1
* Low mountains: Found near stream divides, typically ranging from 2,000 to 3,000 feet (600 to 900 metres) in elevation.1
* Tabular plateaus: Capped with resistant sandstone, these formations reach the highest elevations, such as Mount Roraima (9,094 feet [2,772 metres]).1

While the broader massif covers parts of Venezuela, Brazil, Colombia, and the Guianas, most of French Guiana itself is low-lying due to extensive erosion by rivers flowing toward the Atlantic. The region is predominantly covered by dense tropical rainforest and is rich in mineral deposits, though the heavy vegetation often complicates exploration.12