The Furongian is the fourth and final epoch and series of the Cambrian. It lasted from 497 to 485.4 million years ago. It succeeds the Miaolingian series of the Cambrian and precedes the Lower Ordovician Tremadocian Stage. It is subdivided into three stages: the Paibian, Jiangshanian and the unnamed 10th stage of the Cambrian.[4]

Furongian
~497 – 485.4 ± 1.9 Ma
Chronology
Etymology
Name formalityFormal
Name ratified2003
Former name(s)Cambrian Series 4
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitEpoch
Stratigraphic unitSeries
First proposed byShanchi et. al, 2002
Time span formalityFormal
Lower boundary definitionFAD of the Trilobite Glyptagnostus reticulatus
Lower boundary GSSPPaibi section, Paibi, Hunan, China
28°23′22″N 109°31′33″E / 28.3895°N 109.5257°E / 28.3895; 109.5257
GSSP ratified2003[2]
Upper boundary definitionFAD of the Conodont Iapetognathus fluctivagus.
Upper boundary GSSPGreenpoint section, Green Point, Newfoundland, Canada
49°40′58″N 57°57′55″W / 49.6829°N 57.9653°W / 49.6829; -57.9653
GSSP ratified2000[3]

NamingEdit

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".[5]

DefinitionEdit

The lower boundary is defined in the same way as the GSSP of the Paibian Stage. Both begin with the first appearance of the trilobite Glyptagnostus reticulatus around 497 million years ago.[6] The upper boundary is the lower boundary and GSSP of the Tremadocian Stage which is the first appearance of the conodont Iapetognathus fluctivagus around 485.4 million years ago.[7]

SubdivisionsEdit

The following table shows the subdivisions of the Furongian series/epoch:[4]

Series Stage Age (Ma)
Lower Ordovician
Floian 477.7
Tremadocian 485.4
Furongian
Stage 10 489.5
Jiangshanian 494
Paibian 497
Series 3
Guzhangian 500.5
Drumian 504.5
Wuliuan 509

BiostratigraphyEdit

The base of two of three stages of the Furongian are defined as the first appearance of a trilobite. The base of the Paibian is the first appearance of Glyptagnostus reticulatus and the base of the Jiangshanian is the first appearance of Agnostotes orientalis.[5][8] The still unnamed Cambrian Stage 10 might be defined as the first appearance of Lotagnostus americanus or the conodont Eoconodontus notchpeakensis.[9]

The Furongian can be divided into a number of trilobite zones:

Series Stage Trilobite zone Trilobite GSSP
Furongian Stage 10 Saukia zone (upper part), Eurekia apopsis zone, Tangshanaspis Zone, Parakoldinioidiazone, Symphysurina zone[9] Lotagnostus americanus (undecided)
Jiangshanian Ellipsocephaloides zone, Saukia zone (lower part)[9] Agnostotes orientalis
Paibian ? (?) Glyptagnostus reticulatus
Cedaria

ReferencesEdit

  1. ^ "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
  2. ^ 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.
  3. ^ Cooper, Roger; Nowlan, Godfrey; Williams, S. H. (March 2001). "Global Stratotype Section and Point for base of the Ordovician System" (PDF). Episodes. 24 (1): 19–28. doi:10.18814/epiiugs/2001/v24i1/005. Retrieved 6 December 2020.
  4. ^ a b "GSSP Table - Paleozoic Era". Geologic Timescale Foundation. Retrieved 17 November 2012.
  5. ^ a b Peng, Shanchi; Babcock, Loren; Robison, Richard; Lin, Huanling; Rees, Margaret; Saltzman, Matthew (30 November 2004). "Global Standard Stratotype-section and Point (GSSP) of the Furongian Series and Paibian Stage (Cambrian)" (PDF). Lethaia. 37 (4): 365–379. doi:10.1080/00241160410002081. Retrieved 14 September 2012.
  6. ^ "GSSP for the Paibian". Retrieved 12 November 2012.
  7. ^ "GSSP for the Cambrian - Ordovician Boundary". Retrieved 17 November 2012.
  8. ^ "GSSP for Jiangshanian". Retrieved 12 November 2012.
  9. ^ a b c Landing, E.; Westrop, S.R.; Adrain, J.M. (19 September 2011). "The Lawsonian Stage - the Eoconodontus notchpeakensis FAD and HERB carbon isotope excursion define a globally correlatable terminal Cambrian stage". Bulletin of Geosciences: 621–640. doi:10.3140/bull.geosci.1251.