Mid-Labrador Ridge

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The Mid-Labrador Ridge was a mid-ocean ridge in the Labrador Sea that represented a divergent boundary between the Greenland and North American plates during the Paleogene. The ridge extended from the South Greenland Triple Junction in the southeast to the Davis Strait area in the northwest. [1] Seafloor spreading along the Mid-Labrador Ridge discontinued about 40 million years ago when the mid-ocean ridge became essentially extinct. [2]

The Mid-Labrador Ridge is now mostly buried under sediment, exposed only as a northwesterly trend of seamounts in the southeastern part of the Labrador Basin. [3]

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Index of Greenland-related articles Wikipedia index

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The South Greenland Triple Junction was a geologic triple junction in the North Atlantic Ocean that divided the North American, Greenland and Eurasian plates. It existed during the Paleogene and consisted of the Mid-Labrador and Mid-Atlantic ridges. The triple junction became extinct when seafloor spreading along the Mid-Labrador Ridge ceased during the Eocene.

Canadian Arctic Rift System North American geological structure

The Canadian Arctic Rift System is a major North American geological structure extending from the Labrador Sea in the southeast through Davis Strait, Baffin Bay and the Arctic Archipelago in the northwest. It consists of a series of interconnected rifts that formed during the Paleozoic, Mesozoic and Cenozoic eras. Extensional stresses along the entire length of the rift system have resulted in a variety of tectonic features, including grabens, half-grabens, basins and faults.

References

  1. Oakey, Gordon N.; Stephenson, Randell (2008). "Crustal structure of the Innuitian region of Arctic Canada and Greenland from gravity modelling: implications for the Palaeogene Eurekan orogen". Geophysical Journal International . Royal Astronomical Society. 173 (3): 1041. doi: 10.1111/j.1365-246X.2008.03784.x . ISSN   0956-540X.
  2. Herman, Yvonne (1974). Marine Geology and Oceanography of the Arctic Seas. Springer-Verlag. p. 92. ISBN   978-3-642-87413-0.
  3. Litvin, V. M. (1984). The Morphostructure of the Atlantic Ocean Floor: Its Development in the Meso-Cenozoic. Dordrecht, Holland: D. Reidel Publishing Company. p. 29. ISBN   978-94-009-6247-7.