Guzhangian
~500.5 – ~497 Ma
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Chronology
Etymology
Name formalityFormal
Name ratified2008[2]
Former name(s)Cambrian Stage 7
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
First proposed byShanchi et al., 2007[3]
Time span formalityFormal
Lower boundary definitionFAD of the Trilobite Lejopyge laevigata
Lower boundary GSSPLuoyixi section, Luoyixi, Guzhang, Hunan, China
28°43′12″N 109°57′53″E / 28.7200°N 109.9647°E / 28.7200; 109.9647
Lower GSSP ratified2008[2]
Upper boundary definitionFAD of the Trilobite Glyptagnostus reticulatus
Upper boundary GSSPPaibi section, Paibi, Hunan, China
28°23′22″N 109°31′33″E / 28.3895°N 109.5257°E / 28.3895; 109.5257
Upper GSSP ratified2003[4]

28°43′12″N 109°57′53″E / 28.7200°N 109.9647°E / 28.7200; 109.9647 The Guzhangian is an uppermost stage of the Miaolingian Series of the Cambrian. It follows the Drumian Stage and precedes the Paibian Stage of the Furongian Series. The base is defined as the first appearance of the trilobite Lejopyge laevigata around 500.5 million years ago. The Guzhangian-Paibian boundary is marked by the first appearance of the trilobite Glyptagnostus reticulatus around 497 million years ago.[5]

The name Guzhangian is derived from Guzhang County, Hunan Province, China.

The GSSP is defined in the Huaqiao Formation in Hunan.[6] The precise base of the Guzhangian is a limestone layer 121.3 m above the base Huaqiao Formation(花桥组) at the Louyixi section (28°43′12″N 109°57′53″E / 28.7200°N 109.9647°E / 28.7200; 109.9647), where Lejopyge laevigata has its first appearance.[5]

References

  1. ^ "Chart/Time Scale". stratigraphy.org. International Commission on Stratigraphy.
  2. ^ a b Peng, Shanchi; Babcock, Loren; Zuo, Jingxun; Lin, Huanling; Zhu, Xuejian; Yang, Xianfeng; Robison, Richard; Qi, Yuping; Bagnoli, Gabriella; Chen, Yong’an (March 2009). "The Global Boundary Stratotype Section and Point (GSSP) of the Guzhangian Stage (Cambrian) in the Wuling Mountains, Northwestern Hunan, China". Episodes. 32 (1): 41–55. doi:10.18814/epiiugs/2009/v32i1/006. Retrieved 13 December 2020.
  3. ^ Shanchi, Peng; Babcock, Loren; Jingxun, Zuo; Huanling, Lin; Xuejian, Zhu; Xianfeng, Yang; Robison, Richard; Yuping, Qi; Bagnoli, Gabriella; Yong’an, Chen. "PROPOSED GLOBAL STANDARD STRATOTYPE-SECTION AND POINT FOR THE GUZHANGIAN STAGE (CAMBRIAN)". International Subcommission on Cretaceous Stratigraphy. International Subcommission on Cambrian Stratigraphy. Retrieved 13 December 2020.
  4. ^ Peng, S. C.; Babcock, L. E.; Robison, R. A.; Lin, H. L.; Rees, M. N.; Saltzman, M. R. (2004). "Global Standard Stratotype-Section and Point (GSSP) of the Furongian Series and Paibian Stage (Cambrian)". Lethaia. 37 (4): 365–379. doi:10.1080/00241160410002081. Retrieved 8 December 2020.
  5. ^ a b "GSSP for Guzhangian Stage". Retrieved 12 November 2012.
  6. ^ Peng, Shanchi; Loren E. Babcok; Jingxun Zuo; Huanling LIn; Xuejian Zhu; Xianfeng Yang; Richard A. Robison; Yuping Qui; Gabriella Bagnoli; Yong'an Chen (2009). "The Global Boundary Stratotype Section and Point (GSSP) of the Guzhangian Stage (Cambrian) in the Wuling Mountains, Northwestern Hunan, China" (PDF). Episodes. 32 (1): 41–55. doi:10.18814/epiiugs/2009/v32i1/006. Retrieved 14 September 2012.[dead link]


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