The Guzhangian is an uppermost

stage Stage or stages may refer to: Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly British theatre newspaper * Sta ...

of the

Miaolingian The Miaolingian is the third Series of the Cambrian Period, and was formally named in 2018. It lasted from about to million years ago and is divided in ascending order into 3 stages: the Wuliuan, Drumian, and Guzhangian. The Miaolingian is pr ...

Series of the

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

. It follows the

Drumian The Drumian is a stage of the Miaolingian Series of the Cambrian. It succeeds the Wuliuan and precedes the Guzhangian. The base is defined as the first appearance of the trilobite '' Ptychagnostus atavus'' around million years ago. The top i ...

Stage and precedes the

Paibian The Paibian is the lowest stage of Furongian series of the Cambrian. It follows the Guzhangian ( 3rd series of the Cambrian) and is succeeded by the Jiangshanian Stage. The base is defined as the first appearance of the trilobite '' Glyptagnostus ...

Stage of the

Furongian The Furongian is the fourth and final epoch and series of the Cambrian. It lasted from to million years ago. It succeeds the Miaolingian series of the Cambrian and precedes the Lower Ordovician Tremadocian Stage. It is subdivided into three ...

Series. The base is defined as the first appearance of the trilobite ''

Lejopyge laevigata ''Lejopyge laevigata'' is a species of agnostid trilobite belonging to the genus '' Lejopyge''. It existed during the Guzhangian to the Paibian Age (around to million years ago) of the Cambrian. It has a cosmopolitan distribution and is an ...

'' around million years ago. The Guzhangian-Paibian boundary is marked by the first appearance of the trilobite ''

Glyptagnostus reticulatus ''Glyptagnostus reticulatus'' is a species of agnostid trilobite belonging to the genus '' Glyptagnostus''. It existed during the Paibian Age ( million years ago) of the Cambrian. It has a cosmopolitan distribution and is an important index fos ...

'' around million years ago. The name Guzhangian is derived from

Guzhang County Guzhang County () is a county of Hunan Province, China. The county is the 2nd least populous administrative unit of the counties or county-level cities (after Shaoshan City) in the province, it is under the administration of Xiangxi Autonomous ...

Hunan Province Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi t ...

, China. The

GSSP A Global Boundary Stratotype Section and Point (GSSP) is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted b ...

is defined in the

Huaqiao Formation Huaqiao may refer to: *Overseas Chinese (华侨), or Huaqiao in pinyin *Huaqiao University (华侨大学), in Quanzhou, Fujian *Huaqiao railway station (花桥站), station of the Shanghai-Nanjing Intercity High-Speed Railway in Shanghai *Huaqiao s ...

in Hunan. The precise base of the Guzhangian is a limestone layer 121.3 m above the base Huaqiao Formation(花桥组) at the

Louyixi Luoyixi Town () is a Town in Guzhang County of China's Hunan Province. It is located on a bay of the Fengtan Reservoir (formerly, a southern tributary of the You River). As of the census of 2010, it has a total population of 10,000. Hongshilin (� ...

section (), where ''

'' has its first appearance.

References

Cambrian geochronology Geological ages Geologic formations of China {{geology-stub