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In the geologic timescale, the Wuchiapingian or Wujiapingian (from in the Liangshan area of Hanzhong, Shaanxi Province〔(【引用サイトリンク】 title= 陕西汉中梁山吴家坪灰岩的再研究 (Restudies on the Wujiaping Limestone Liangshan of Hanzhong, Shaanxi) )〕) is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian epoch or series. The Wuchiapingian spans the time between and million years ago (Ma). It was preceded by the Capitanian and followed by the Changhsingian.〔See Gradstein ''et al.'' (2004) for a detailed geologic timescale〕 Regional stages with which the Wuchiapingian is coeval or overlaps include the Djulfian or Dzhulfian, Longtanian, Rustlerian, Saladoan, and Castilian.〔(【引用サイトリンク】title =Wuchiapingian )〕 ==Stratigraphic definitions== The Wuchiapingian was first used in 1962, when the Lopingian series of southwestern China was divided in the Changhsingian and Wuchiapingian formations.〔By Sheng (1962)〕 In 1973 the Wuchiapingian was first used as a chronostratigraphic unit (i.e. a stage, as opposed to a formation, which is a lithostratigraphic unit).〔The Wuchiapingian stage was first used by Kanmera & Nakazawa (1973)〕 The base of the Wuchiapingian stage is defined as the place in the stratigraphic record where the conodont species ''Clarkina postbitteri postbitteri'' first appears. A global reference profile for this boundary (a GSSP) is located near Laibin in the Chinese province of Guangxi.〔The GSSP for the Wuchiapingian stage was established by Jin ''et al.'' (2006)〕 The top of the Wuchiapingian (the base of the Changhsingian) is at the first appearance of conodont species ''Clarkina wangi''. The Wuchiapingian contains two ammonite biozones: that of the genus ''Araxoceras'' and that of the genera ''Roadoceras'' and ''Doulingoceras''. 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「Wuchiapingian」の詳細全文を読む スポンサード リンク
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