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The Ladinian is a stage and age in the Middle Triassic series or epoch. It spans the time between Ma and ~235 Ma (million years ago).〔According to Gradstein ''et al.'' (2004). Brack ''et al.'' (2005) give 241 to 235 Ma〕 The Ladinian was preceded by the Anisian and succeeded by the Carnian (part of the Upper or Late Triassic).〔For a detailed geologic timescale see Gradstein ''et al.'' (2004)〕 The Ladinian is coeval with the Falangian Chinese regional stage. ==Stratigraphic definitions== The Ladinian was established by Austrian geologist Alexander Bittner in 1892. Its name comes from the Ladin people that live in the Italian Alps (in the Dolomites, then part of Austria-Hungary). The base of the Ladinian stage is defined as the place in the stratigraphic record where the ammonite species ''Eoprotrachyceras curionii'' first appears. The global reference profile for the base (the GSSP) is at an outcrop in the river bed of the Caffaro river at Bagolino, in the province of Brescia, northern Italy.〔The GSSP was established by Brack ''et al.'' (2005)〕 The top of the Ladinian (the base of the Carnian) is at the first appearance of ammonite species ''Daxatina canadensis''. The Ladinian is sometimes subdivided into two subages or substages, the Fassanian (early or lower) and the Longobardian (late or upper). The Ladinian contains four ammonite biozones, which are evenly distributed among the two substages: *zone of ''Frechites regoledanus'' *zone of ''Protrachyceras archelaus'' *zone of ''Protrachyceras gredleri'' *zone of ''Eoprotrachyceras curionii'' 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「Ladinian」の詳細全文を読む スポンサード リンク
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