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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]
Age (mya) Status GSSP location Defining markers Geographic Coordinates References Pliocene: Piacenzian: 3.6 Punta Piccola Section, Porto Empedocle, Sicily, Italy Magnetic: Base of magnetic polarity chronozone C2An (Gauss). Biologic: Extinction of Globorotalia margaritae and Pulleniatina primalis (Planktonic foraminifera
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 ...
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.
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 Cambrian Drumian carbon isotope excursion (DICE) event is associated with the beginning of this age. [6] The cause of this event was the shallowing of anoxic deep waters simultaneously with their transgression. DICE hampered the recovery of reef ecosystems already affected by the early–middle Cambrian mass extinctions. [7]
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 ...
The Furongian was also known as the Cambrian Series 4, and the name replaced the older term Upper Cambrian and equivalent to the local term Hunanian. The present name was ratified by the International Commission on Stratigraphy in 2003. Fúróng (芙蓉) means 'lotus' in Mandarin and refers to Hunan which is known as the "lotus state". [3]