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Carnian
The Carnian (less commonly, Karnian) is the lowermost stage of the Upper Triassic series (or earliest age of the Late Triassic epoch). It lasted from about 228 to about 235 million years ago (Ma).〔According to Gradstein ''et al.'' (2004). Brack ''et al.'' (2005) give 235 to 226 Ma〕 The Carnian is preceded by the Ladinian and is followed by the Norian. Its boundaries are not characterized by major extinctions or biotic turnovers, but a climatic event (known as the Carnian Pluvial Event) occurred during the Carnian and seems to be associated with important extinctions or biotic radiations.
==Stratigraphic definitions==
The Carnian was named in 1869 by Mojsisovics. It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia (''Kärnten'' in German). The name, however, was first used referring to a part of the Hallstatt Limestone cropping out in Austria.
The base of the Carnian stage is defined as the place in the stratigraphic record where the ammonite species ''Daxatina canadensis'' first appears. The global reference profile for the base is located at the ''Stuores-Wiesen'' near Badia in the Val Badia in the region of South Tyrol, Italy.〔The GSSP was established by Broglio Loriga ''et al.'' (1999)〕
The top of the Carnian (the base of the Norian) is at the bases of the ammonite biozones of ''Klamathites macrolobatus'' or ''Stikinoceras kerri'' and the conodont biozones of ''Metapolygnathus communisti'' or ''Metaolygnathus primitius''.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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