翻訳と辞書 Words near each other ・ Rithy Panh ・ Riti (name) ・ Riti Pathak ・ Ritiati ・ Ritidian Point ・ Ritigala ・ Ritimyinga ・ Ritini ・ Ritinis ・ Ritiometan ・ Ritipenem ・ Ritiševo ・ Ritjaw ・ Ritjawng ・ Ritlal Yadav ・ Ritland crater ・ Ritli Hill ・ RITM-200 ・ Ritman University ・ Ritmerk ・ Ritmo ・ Ritmo a todo color ・ Ritmo Ardiente ・ Ritmo bellunese ・ Ritmo cassinese ・ Ritmo de la noche ・ Ritmo Del Amor ・ Ritmo Deportivo ・ Ritmo di Sant'Alessio ・ Ritmo lucchese Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Ritland crater ： ウィキペディア英語版 Ritland crater The Ritland crater is an impact crater at the farm Ritland in Hjelmeland, Rogaland County, Norway. It is about in diameter, and was created when a meteorite with an estimated diameter of struck 500–600 million years ago. The crater was later buried by sediments, of which it has been partly recovered. The structure was first discovered as a possible (suspected) impact crater in 2000 by geologist Fridtjof Riis. The Research Council of Norway has funded scientific research of the crater. In 2009, scientists from the University of Oslo considered it proven that the crater was formed by meteorite impact, according to Professor Henning Dypvik from the Institute for Geological Sciences at the University of Oslo. ==Details== The sediments and fossils at Ritland have been studied by geologists since the 1950s. The depth of the circular structure is about , with a diameter of about . Research has focused on trying to find evidence that the crater resulted from a meteoric impact. In 2008 it was announced that microscopic evidence was found, and that the structure is an impact crater. The crater dates from before mid Cambrian, as fossils from mid Cambrian are found in sediments that have accumulated in the crater. The evidence for the structure being an impact crater stems from identification of shocked quartz particles, which only form under the very high pressures (5-10 GPa) present during a meteoric impact.〔 The sediments in the crater are described as landslides in the bottom of the crater, followed by shale sediments deposited during a period when the sea had invaded the area. On top of the clay sediments are coarser sediments. During the Caledonian orogeny the crater was buried under a several kilometre thick mountain chain. The overlaying mountains were later eroded, and the crater was again exposed.〔 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「Ritland crater」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.