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The Zanclian is the lowest stage or earliest age on the geologic time scale of the Pliocene. It spans the time between 5.332 ± 0.005 Ma and 3.6 ± 0.005 Ma (million years ago). It is preceded by the Messinian age of the Miocene epoch, and followed by the Piacenzian age. The Zanclian can be correlated with regionally used stages, such as the Tabianian or Dacian of Central Europe. It also corresponds to the late Hemphillian to mid-Blancan North American Land Mammal Ages. In California, the Zanclian roughly corresponds to the mid-Delmontian Californian Stage of from 7.5 To 2.9 Ma ago. ==Definition== The Zanclian stage was introduced by Giuseppe Seguenza in 1868. It is named after ''Zancle'', the pre-Roman name for the Italian city of Messina on Sicily. The base of the Zanclian (and the Pliocene series) lies with the top of magnetic chronozone Cr3 (about 100,000 years before the Thvera normal subchronozone C3n.4n). The base is also close to the extinction level of the calcareous nanoplankton species ''Triquetrorhabdulus rugosus'' (the base of biozone CN10b) and the first appearance of nanoplankton ''Ceratolithus acutus''. The GSSP for the Zanclian is in the vicinity of the ruins of the ancient city of Heraclea Minoa on Sicily, Italy.〔Van Couvering ''et al.'' (2000)〕 The top of the Zanclian stage (the base of the Piacenzian stage) is at the base of magnetic chronozone C2An (the base of the Gauss chronozone and at the extinction of the planktonic forams ''Globorotalia margaritae'' and ''Pulleniatina primalis''. 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「Zanclean」の詳細全文を読む スポンサード リンク
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