The Nagssugtoqidian orogeny was a late

Paleoproterozoic The Paleoproterozoic Era (;, also spelled Palaeoproterozoic), spanning the time period from (2.5–1.6 Ga), is the first of the three sub-divisions (eras) of the Proterozoic Eon. The Paleoproterozoic is also the longest era of the Earth's ...

mountain-building event that affected

Greenland Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is t ...

during the period 1.91 to 1.77 Ga. The orogenic belt formed during this event marks the northern boundary of the mainly Archaean

North Atlantic Craton The North Atlantic Craton (NAC) is an Archaean craton exposed in southern West Greenland, the Nain Province in Labrador, and the Lewisian complex in northwestern Scotland. The NAC is bounded by the Nagssugtoqidian orogen to the north and the 1.8 ...

. It was first recognised by Ramberg in 1949, based on its effect on the

Kangaamiut dike swarm The Kangaamiut dike swarm (old spelling: ''Kangâmiut'') is a 2.04 billion year old dike swarm located in the Qeqqata region of western Greenland. The dikes cut Archean orthogneisses and are exposed along approximately of the coast and a similar ...

. The subsequent recognition of magmatic terranes representing past

island arc Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle alon ...

s and two potential sutures representing now vanished subduction zones within the belt, have enabled its interpretation in terms of

plate tectonics Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large ...

References

{{Reflist Orogenies of North America Proterozoic North America Geology of Greenland Paleoproterozoic orogenies