Mistastin crater

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Mistastin crater
Mistastinlakecrater.jpg
Impact crater/structure
Confidence Confirmed[1]
Diameter 19 kilometres (12 mi)
Age 36.4 ± 4 million years old (Eocene Epoch)
Exposed Yes
Drilled Yes
Location
Location Labrador, Newfoundland and Labrador, Canada
Coordinates 55°53′N 63°18′W / 55.883°N 63.300°W / 55.883; -63.300Coordinates: 55°53′N 63°18′W / 55.883°N 63.300°W / 55.883; -63.300
Mistastin crater is located in Newfoundland and Labrador
Mistastin crater
Mistastin crater
Location of the Mistastin crater in Labrador
Topo map Canada NTS 13M
Mistastin Lake
Coordinates 55°53′N 63°18′W / 55.883°N 63.300°W / 55.883; -63.300
Type impact crater lake
Basin countries Canada
Max. length 19 km (12 mi)
Max. width 12 km (7.5 mi)
Surface area 145 km2 (56 sq mi)
Surface elevation 338 metres (1,109 ft)
Islands Horseshoe Island

Mistastin crater is a meteorite crater in Labrador, Canada which contains the roughly circular Mistastin Lake.[2] The lake is approximately 16 km (9.9 mi) in diameter, while the estimated diameter of the original crater is 28 km (17 mi). The age of the crater is calculated to be 36.4 ± 4 million years (Eocene).

Formation and Geology[edit]

Mistastin crater was created 36 million years ago by a violent asteroid impact.[3] The presence of cubic zirconia around the crater rim suggests that the impact generated temperatures in excess of 2,370 °C, the highest crustal temperatures known on Earth[3] and produced global changes that lasted for decades after the impact.

The lake's arcuate central island is interpreted to be the central uplift of the complex crater structure. The target rocks were part of a batholith composed of adamellite, mangerite and lenses of anorthosite. There are abundant shock metamorphic features exhibited in the rocks of the island. Planar deformation features, diaplectic glass, melt rocks, and shatter cones have been identified.

References[edit]

Further reading[edit]

  • Currie, K.L. (1968) "Mistastin Lake, Labrador: A new Canadian crater". Nature, v. 220, pp. 776–777.
  • Currie, K.L. Larochelle, A. (1969) "A paleomagnetic study of volcanic rocks from Mistastin Lake, Labrador, Canada". Earth and Planetary Science Letters, v. 6, pp. 309–315.
  • Currie, K.L. (1971) "Geology of the resurgent cryptoexplosion crater at Mistastin Lake, Labrador". Geological Survey of Canada Bulletin 207, 62 p.
  • Currie, K.L. (1971) "The composition of anomalous plagioclase glass and coexisting plagioclase from Mistastin Lake, Labrador, Canada". Mineralogical Magazine, v. 38, pp. 511–517.
  • Grieve, R.A.F. (1975) "Petrology and chemistry of the impact melt at Mistastin Lake crater, Labrador". Geological Society of America Bulletin 86, pp. 1617–1629.
  • Mak, E.K.C. York, D., Grieve, R.A.F. and Dence, M.R. (1976) "The age of the Mistastin Lake crater, Labrador, Canada". Earth and Planetary Science Letters, v. 31, pp. 345–357.
  • Marchand, M. Crocket, J.H. (1977) "Sr isotopes and trace element geochemistry of the impact melt and target rocks at the Mistastin Lake crater, Labrador". Geochimica et Cosmochimica Acta, v. 41, pp. 1487–1495.

External links[edit]