Miaolingian
| Miaolingian | |||||||
|---|---|---|---|---|---|---|---|
| Chronology | |||||||
| |||||||
| |||||||
Subdivision of the Cambrian according to the Epoch | |||||||
| Stratigraphic unit | Series | ||||||
| Time span formality | Formal | ||||||
| Lower boundary definition | FAD of the Trilobite Oryctocephalus indicus. | ||||||
| Lower boundary GSSP | Wuliu-Zengjiayan, Guizhou, China 26°04′51″N 108°24′50″E / 26.0807°N 108.4138°E | ||||||
| Lower GSSP ratified | 2018[2] | ||||||
| Upper boundary definition | FAD of the Trilobite Glyptagnostus reticulatus | ||||||
| Upper boundary GSSP | Paibi section, Paibi, Hunan, China 28°23′22″N 109°31′33″E / 28.3895°N 109.5257°E | ||||||
| Upper GSSP ratified | 2003[3] | ||||||
The Miaolingian is the third Series of the Cambrian Period, and was formally named in 2018.[4] It lasted from about 509 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]
Definition
A number of proposals for fossils and type sections were made before it was formally ratified in 2018. The most promising fossil markers were seen to be the respective first appearances of either trilobite species Ovatoryctocara granulata or Oryctocephalus indicus,[6] which both have an age close to 509 million years ago.[5] After some deliberation, the FAD of Oryctocephalus indicus was chosen to be the lower boundary marker, and the GSSP was placed in Wuliu-Zengjiayan, Guizhou, China.[2]
The Miaolingian-Furongian boundary has the same definition as the Paibian Stage. It is defined as the first appearance of Glyptagnostus reticulatus around 497 million years ago.[5]
Subdivision
The Miaolingian is subdivided into the following stages:[5]
| Epoch | Stage | Age lower boundary (mya) |
|---|---|---|
| Furongian | ||
| Stage 10 | 489.5 | |
| Jiangshanian | 494 | |
| Paibian | 497 | |
| Miaolingian | ||
| Guzhangian | 500.5 | |
| Drumian | 504.5 | |
| Wuliuan | 509 | |
| Series 2 | ||
| Stage 4 | 514 | |
| Stage 3 | 521 |
References
- ^ "Chart/Time Scale". stratigraphy.org. International Commission on Stratigraphy.
- ^ . Retrieved 8 December 2020.
- . Retrieved 8 December 2020.
- ^ "Archived copy" (PDF). Archived from the original (PDF) on 2018-09-07. Retrieved 2020-05-16.
{{cite web}}: CS1 maint: archived copy as title (link) - ^ a b c d "GSSP Table - Paleozoic Era". Retrieved 15 November 2012.
- S2CID 129084517.
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