Gweni-Fada crater | |
---|---|
Impact crater/structure | |
Confidence | Confirmed |
Diameter | 14 km (8.7 mi) |
Age | <345 Ma <Early Carboniferous |
Exposed | Yes |
Drilled | No |
Location | |
Location | Sahara |
Coordinates | 17°25′7″N21°45′8″E / 17.41861°N 21.75222°E |
Country | Chad |
State | Ennedi-Ouest |
Gweni-Fada is a meteorite crater in the Ennedi Plateau, Chad. [1] [2]
The Gweni Fada structure was first noted on the map NE 34 X Fada of the IGN (National Geographic Institute France) and aerial photographs in the 1950s of IGN by Alain Beauvilain (Paris X- Nanterre University). In April 1995, at the initiative of CNAR (National Center to Help Research of Chad) a team of French geologists (Pierre Vincent, University of Clermont-Ferrand, Alain and Najia Beauvilain, CNAR Chad) visited the site and reported evidence of shock metamorphism within rock samples they had collected inside the structure.
Centered at 17°25′N and 21°45′E, being slightly wider in the NW-SE direction (cf. topographic map), the asymmetric structure is deeply eroded. A broad depression (ø 12 km) forms a crescent around two thirds of the inner complex zone. On the northern side, an elevated outer ring of outward-dipping sandstones surrounds the depression. In its south, the external depression is absent. The inner zone (ø 10 km) consists of a rugged terrain with hills several hundred meters in height. The latter may be remnants of the central uplift (see topographic map).
The age is estimated to be less than 345 million years (Carboniferous). It is older than that of Aorounga because its coverage of impactite has disappeared as a result of erosion.
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Aorounga is an eroded meteorite impact crater in Chad, Africa. The exposed remnant of the crater is 12.6 km (7.8 mi) in diameter and its age is estimated to be less than 345 million years.
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Woodleigh is a large meteorite impact crater (astrobleme) in Western Australia, centred on Woodleigh Station east of Shark Bay, Gascoyne region. A team of four scientists at the Geological Survey of Western Australia and the Australian National University, led by Arthur J. Mory, announced the discovery in the 15 April 2000 issue of Earth and Planetary Science Letters.
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Christian Köberl is a professor of impact research and planetary geology at the University of Vienna, Austria. From June 2010 to May 2020 he was director general of the Natural History Museum in Vienna. He is best known for his research on meteorite impact craters.