The Eurekan orogeny was a Phanerozoic

mountain building Mountain formation refers to the geological processes that underlie the formation of mountains. These processes are associated with large-scale movements of the Earth's crust (tectonic plates). Folding, faulting, volcanic activity, igneous int ...

event that affected the eastern portion of the Arctic Archipelago and, to a lesser extent, northern

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 i ...

Deformation Deformation can refer to: * Deformation (engineering), changes in an object's shape or form due to the application of a force or forces. ** Deformation (physics), such changes considered and analyzed as displacements of continuum bodies. * Defor ...

initiated in the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...

, during which time the Sverdrup Basin began to fragment and fold in response to the counterclockwise rotation of Greenland, caused by

seafloor spreading Seafloor spreading or Seafloor spread is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. History of study Earlier theories by Alfred Wegener a ...

in the Canadian Arctic Rift System. Isostatic uplift was most pronounced in the Grantland Mountains and Victoria and Albert Mountains on Ellesmere Island and in the Princess Margaret Range on Axel Heiberg Island, as evidenced by the current

physiography Physical geography (also known as physiography) is one of the three main branches of geography. Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere, h ...

. Compression in a broad zone on Ellesmere Island resulted in the formation of the Eurekan Fold Belt. The Eurekan orogeny came to an end when seafloor spreading in the

Labrador Sea The Labrador Sea (French: ''mer du Labrador'', Danish: ''Labradorhavet'') is an arm of the North Atlantic Ocean between the Labrador Peninsula and Greenland. The sea is flanked by continental shelves to the southwest, northwest, and northeast. It ...

ceased about 33 million years ago during the Oligocene

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

. Erosion of the

orogenic Orogeny is a mountain building process. An orogeny is an event that takes place at a convergent plate margin when plate motion compresses the margin. An ''orogenic belt'' or ''orogen'' develops as the compressed plate crumples and is uplifted t ...

mountains followed, resulting in the deposition of undeformed sediment above the eroded remnants of deformed rock. At least some of the coarse clastic sediments in the Beaufort Formation were derived from the Grantland Mountains and Princess Margaret Range, suggesting that these ranges had higher elevations during the Late Miocene or

Early Pliocene Early may refer to: History * The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.: ** Early Christianity ** Early modern Europe Places in the United States * Early, Iowa * Early, Texas * Early ...

times.

References

{{Nunavut-geo-stub Orogenies of North America Cretaceous orogenies Paleogene orogenies Geology of Nunavut Geology of Greenland Queen Elizabeth Islands