Answer: Canada
Notes: The Acasta Gneiss is located in the Northwest Territories of Canada. The rock is exposed on an island about 300 kilometers north of Yellowknife. The Acasta Gneiss is one of the oldest known intact crustal fragments on Earth. The rock was metamorphosed between 3.58 and 4.031 billion years ago. The Acasta Gneiss was first described in 1989. It was discovered during fieldwork in 1983 by Geological Survey of Canada geologist Janet King. Gneiss is a type of rock that has been metamorphosed by intense heat and pressure at depth in Earth's crust. The original, unmetamorphosed rock was a granite, an intrusive igneous rock.
This Question is Also Available in:
हिन्दी