Geological Setting

Regional Geology

The Guyana Shield (Shield) is the northern Amazon Craton, which was part of the West African Craton until the Atlantic Ocean opened about 115 Ma ago. The Amazon Craton was divided into provinces based on age determinations, structural trends, proportion of lithologies and geophysical trends. The Proterozoic greenstone areas of Guyana are in the Pastora-Amapa Province (2.2 Ga to 1.95 Ga} and consists of metavolcanic and metasedimentary rocks. Tropical weathering has transformed the upper 100 m of the Shield into a saprolite, highly variable in thickness but which can be mined at a relatively low cost.

Local Geology
The Barama, Cuyuni and Mazaruni are the greenstone belts in Guyana. The Aurora and Aranka Prospects are in the Cuyuni belt, which consists of, basalts, overlain by andesite rhyolites, overlain by shales and graywackes. Ultramafic and carbonate rocks occur locally. Most rocks were deformed by the Trans-Amazonian Orogeny (2.0 Ga). Brittle faults trending north-northwest or north-northeast were intruded by mafic dikes and northnortheast faults displaced mineralized zones.

There are a number of gold mines and gold occurrences in Guyana, Venezuela, Surinam and French Guiana.