Pingualuit crater
Pingualuit Crater
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| Planet | Earth |
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| Coordinates | 61°16′30″N 73°39′37″W / 61.274997°N 73.660278°WCoordinates: 61°16′30″N 73°39′37″W / 61.274997°N 73.660278°W |
| Diameter | 3.44 km (2.14 mi) |
| Depth | 400 m (1,300 ft) |
| Discoverer | Frederick W. Chubb |
The Pingualuit Crater (French: cratère des Pingualuit; Inuktitut, "where the land rises"), formerly called Chubb Crater and later New Quebec Crater (cratère du Nouveau-Québec), is a young impact crater, by geological standards, located on the Ungava Peninsula, in the administrative region of Nord-du-Québec, in Quebec, Canada. It is 3.44 km (2.14 mi) in diameter, and is estimated to be 1.4 ± 0.1 million years old ().
The crater is exposed to the surface, rising 160 m (520 ft) above the surrounding tundra and is 400 m (1,300 ft) deep. The 267 m (876 ft) deep annular Pingualuk Lake fills the hollow, and is one of the deepest lakes in North America. The lake also holds some of the purest fresh water in the world, with a salinity level of less than 3 ppm (the salinity level of the Great Lakes is 500 ppm). The lake has no inlets or apparent outlets, so the water accumulates solely from rain and snow and is only lost through evaporation. It is one of the most transparent lakes in the world, with Secchi disk visible more than 35 m (115 ft) deep.
The crater was formed by a meteorite impact 1.4 Ma, as estimated by 40Ar/39Ar dating of impact melt rocks. An analysis of these rocks also revealed planar deformation features as well as the composition of the meteorite itself. The Ir, Ni, Co and Cr enrichments found in impact melt samples suggest that the meteorite was chondritic in nature.
Largely unknown to the outside world, the lake-filled crater had long been known to local Inuit who knew it as the "Crystal Eye of Nunavik" for its clear water. World War II pilots often used the almost perfectly circular landmark as a navigational tool.
On June 20, 1943, a United States Army Air Force plane on a meteorological flight over the Ungava region of Quebec Province took a photograph that showed the wide crater rim rising up above the landscape. In 1948 the Royal Canadian Air Force covered the same remote area as part of its program of photomapping Canada, however these photographs were not made publicly available until 1950.
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Wikipedia