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:''There is also a Darwin crater on the moon and a Darwin crater on Mars'' Darwin Crater is a suspected meteorite impact crater in Western Tasmania. It is expressed as a rimless circular flat-floored depression, in diameter, within mountainous and heavily forested terrain south of Queenstown. It lies east of the West Coast Range and the former North Mount Lyell Railway formation, and just within the Franklin-Gordon Wild Rivers National Park. The crater was discovered by the geologist R. J. Ford in 1972, after a search for the source of Darwin glass, an impact glass found over more than of southwestern Tasmania. Geophysical investigations and drilling have shown that the crater is filled with up to of breccia capped by Pleistocene lake sediments. Although definitive proof of an impact origin of the crater is lacking, the impact hypothesis is strongly supported by the relationship of the glass to the crater, as well as the stratigraphy and deformation of the crater-filling material.〔 If the crater is indeed the source of the glass, the age of Darwin Crater is 816,000 ± 7,000 years—the age of Darwin glass as determined by argon dating methods. A 2004 thesis from the University of Tasmania was focused specifically on the glass material origins ==References== 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「Darwin Crater」の詳細全文を読む スポンサード リンク
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