Jiangshanium
system | series | step | ≈ age ( mya ) |
---|---|---|---|
higher | higher | higher | younger |
Cambrian | Furongium | 10th stage | 485.4 ⬍ 489.5 |
Jiangshanium | 489.5 ⬍ 494 |
||
Paibium | 494 ⬍ 497 |
||
Miaolingium | Guzhangium | 497 ⬍ 500.5 |
|
Drumium | 500.5 ⬍ 504.5 |
||
Wuliuum | 504.5 ⬍ 509 |
||
2nd series | 4th stage | 509 ⬍ 514 |
|
3rd stage | 514 ⬍ 521 |
||
Terreneuvium | 2nd stage | 521 ⬍ 529 |
|
Fortunium | 529 ⬍ 541 |
||
deeper |
The Jiangshanium is the middle chronostratigraphic stage of the Furongian series of the Cambrian in geological history . The Jiangshanium is underlain by the Paibium and overlaid by the as yet unnamed 10th stage of the Cambrian. The Jiangshanium lasted approximately from 494 million years to 489.5 million years (interpolated).
Naming and history
The name of the stage was ratified in September 2011. It is named after the Chinese town of Jiangshan in Zhejiang Province .
Definition and GSSP
The lower limit is due to the first appearance of the globally occurring trilobite species Agnostotes orientalis . It also correlates with the first appearance of the trilobite species Irvingella angustilimbata . The upper limit will presumably be defined by the first appearance of the trilobite species Lotagnostus americanus . The 10th stage of the Cambrian has not yet been named and the lower limit has not yet been formally established.
The GSSP (Global Standard-stratotype Section and Points) is a profile in the village of Duibian (Duibian B Section), north of Jiangshan (western Zhejiang province, China). The GSSP is in profile 108.12 m above the base of the Huayansi Formation.
literature
- Peng Shanchi, Zhu Xuejian, Zuo Jinxun, Lin Huanling, Chen Yong'an, Wang Longwu: Recently Ratified and Proposed Cambrian Global Standard Stratotype-section and Points. Acta Geologica Sinica, 2011 (2): 296-308 abstract