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This list is divided first into the geologic eras of the Phanerozoic (the Cenozoic, the Mesozoic, and the Paleozoic) and then into the geologic periods of each era.Each period is marked below the era bar on top of its subdivided epochs and stages.
The Miaolingian is the third Series of the Cambrian Period, and was formally named in 2018. [4] It lasted from about 506.5 to 497 million years ago and is divided in ascending order into 3 stages: the Wuliuan, Drumian, and Guzhangian. The Miaolingian is preceded by the unnamed Cambrian Series 2 and succeeded by the Furongian series. [5]
The Cambrian (/ ˈ k æ m b r i. ə n, ˈ k eɪ m-/ KAM-bree-ən, KAYM-) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. [5] The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovician Period 486.85 Ma.
The Wuliuan stage is the fifth stage of the Cambrian, and the first stage of the Miaolingian Series of the Cambrian. It was formally defined by the International Commission on Stratigraphy in 2018. [5]
The Precambrian-Cambrian boundary GSSP at Fortune Head, Newfoundland is a typical GSSP. It is accessible by paved road and is set aside as a nature preserve. A continuous section is available from beds that are clearly Precambrian into beds that are clearly Cambrian.
Volcanic activity, particularly that of large igneous provinces, has been speculated to have been the cause of the environmental crisis. [3] The emplacement of the Namaqualand–Garies dykes in South Africa has been dated to 485 mya, the time at which the Cambrian–Ordovician extinction event occurred, although there remains no unambiguous evidence of a causal relationship between this ...
The biota of the Burgess Shale appears to be typical of middle Cambrian deposits. [6] Although the hard-part bearing organisms make up as little as 14% of the community, [6] these same organisms are found in similar proportions in other Cambrian localities. This means that there is no reason to assume that the organisms without hard parts are ...
Avalonia is the largest of the peri-Gondwanan terranes, a series of continental blocks that more or less simultaneously broke off the margins of the southern supercontinent Gondwana and therefore share an early Paleozoic marine fauna. They were pulled northward and eventually collided to form the Appalachian, Caledonide, and Variscan orogens ...