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THE EXTINCTION OF THE DINOSAURS  ~65 million years

The Cretaceous–Tertiary extinction event, which occurred approximately 65.5 million years ago (Ma), was a large-scale mass extinction of animal and plant species in a geologically short period of time. Widely known as the K–T extinction event, it is associated with a geological signature known as the K–T boundary, usually a thin band of sedimentation found in various parts of the world. K is the traditional abbreviation for the Cretaceous Period derived from the German name Kreidezeit, and T is the abbreviation for the Tertiary Period (a historical term for the period of time now covered by the Paleogene and Neogene periods). The event marks the end of the Mesozoic Era and the beginning of the Cenozoic Era. With "Tertiary" being discouraged as a formal time or rock unit by the International Commission on Stratigraphy, the K–T event is now called the Cretaceous–Paleogene (or K–Pg) extinction event by many researchers. (click to see all the article on Wikipedia)

恐龍滅絕 ~65百萬年前

白堊紀-第三紀滅絕事件,發生約在6550萬年前,是地質學上的短期間發生的大規模動植物滅絕事件。這眾所皆知的K-T滅絕事件,與被稱為K-T界線的地質特徵有關,在世界各地都能找到這沈積的薄層。K是白堊紀的縮寫,源自於德文KreidezeitT則是第三紀的縮寫(歷史年代名詞,包含了古近紀與新近紀)。這事件標示著中生代的結束與新生代的開端。由於國際地質委員會不再使用第三紀,作為時間標示或岩石年份單位所用,許多研究人員把K-T滅絕事件稱為白堊紀-古近紀(或是K-Pg)滅絕事件。

(維基連結:白堊紀-第三紀滅絕事件)

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