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Rochechouart is an impact crater in France. Its original diameter before erosion is thought to have been about . Its most recent age estimate is 202.7 ± 2.2 million years ago,〔Jourdan, F., Reimold, W.U., Deutsch, A., 2012. Dating terrestrial impact structures. In: Jourdan, F., Reimold, W.U. (Eds.), Impact! Elements 8, 49–53.〕 placing it in the Rhaetian, close to the Triassic-Jurassic boundary. Since then the crater has been deeply eroded, and no trace of its original surface morphology is visible. The crater appears to be too small to account for the Triassic–Jurassic extinction event.〔 Its centre is tentatively located at the hamlet of La Judie west of Rochechouart, in the Haute-Vienne ''département''; its surface extent includes the communes and villages of Rochechouart, Chaillac, Étagnac, Pressignac, Lésignac-Durand, Saint-Quentin-sur-Charente, Chéronnac, Chassenon and Chabanais. The remnants of this astrobleme have been a major subject of debate among geologists since their discovery in the early 19th century. The explanation was only given in 1969 by the French geologist François Kraut, who definitely proved the impact origin of the breccias. The Rochechouart impact crater was the first crater the nature of which was proven by the determination of the impact effects on the rocks, without any circular topographic features being visible. ==Hypothetical multiple impact event== (詳細はGeophysicist David Rowley of the University of Chicago, working with John Spray of the University of New Brunswick and Simon Kelley of the Open University, that Rochechouart may have been part of a hypothetical multiple impact event which also formed the Manicouagan crater in northern Quebec, Saint Martin crater in Manitoba, Obolon' crater in Ukraine, and Red Wing crater in North Dakota.〔Spray, J.G., Kelley, S.P. and Rowley, D.B. (1998). "Evidence for a late Triassic multiple impact event on Earth". ''Nature'', v. 392, pp. 171-173. (Abstract )〕 All of the craters had previously been known and studied, but their paleoalignment had never before been demonstrated. Rowley has said that the chance that these craters could be aligned like this due to chance are nearly zero. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Rochechouart crater」の詳細全文を読む スポンサード リンク
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