Slave Craton

Area of ancient rocks in northwest Canada

The Slave craton is an Archaean craton in the north-western Canadian Shield, in Northwest Territories and Nunavut. The Slave Craton includes the 4.03 Ga-old Acasta Gneiss which is one of the oldest dated rocks on Earth. Covering about 300,000 km² (120,000 sq mi), it is a relatively small but well-exposed craton dominated by ~2.73–2.63 Ga (billion years-old) greenstones and turbidite sequences and ~2.72–2.58 Ga plutonic rocks, with large parts of the craton underlain by older gneiss and granitoid units.

From Wikipedia, under CC BY-SA. More on occurri.