Archaean gneiss complex of Greenland

The gneiss complex which extends from ltivdleq to Ivigtut on the west coast and from Gyldenl91ves Fjord to Mogens Heinesen Fjord on the east coast (fig. 4) has remained unaffected by major metamorphic, tectonic or magmatic events for the last 2600 m.y. Similar rocks occur in north-west Scotland (Peach et al., 1907 pp. 191-252) and Labrador (Bridgwater et al., 1973c; Bridgwater et al., 1975) and the area described here is the largest and best exposed fragment of the Archaean North Atlantic craton which was broken up by Phanerozoic continental drift. Isolated remnants of similar Archaean rocks occur within the younger mobile belts to the north and south suggesting that the Archaean craton was once much larger and that a large part of it was reworked to varying degrees by younger tectonic and metamorphic events.