Furongian

Key events in the Cambrian

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Fortunian

"Stage 2"

"Stage 3"

"Stage 4"

"Stage 5"

Drumian

Guzhangian

Paibian

Jiangshanian

"Stage 10"

 

 

 

 

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Baykonur
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Baykonur
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Orsten Fauna

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Burgess Shale

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Kaili biota

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Archaeocyatha extinction

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Emu Bay Shale

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Sirius Passet biota

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Chengjiang biota

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First Trilobites

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SSF diversification, first brachiopods & archaeocyatha

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First halkieriids, mollusсs, hyoliths SSF

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Treptichnus pedum trace
Large negative peak δ 13C_carb excursion

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First Cloudina & Namacalathus mineral tubular fossils

Stratigraphic scale of the ICS subdivisions and Precambrian/Cambrian boundary.

The Furongian is the fourth and final series of the Cambrian. It lasted from ~497 to 485.4 ± 1.9 million years ago. It succeeds the still unnamed 3rd 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.

Naming

The Furongian was also known as the "Series 4" of the Cambrian and replaced the older term "Upper Cambrian" and equivalent to the local term "Hunanian". The name "Furongian" was ratified by the International Commission on Stratigraphy in 2003. Furong (芙蓉) means "lotus" in Mandarin and refers to Hunan which is known as the "lotus state".

Definition

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. 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 ± 1.9 million years ago.

Subdivisions

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

Epoch	Stage	Age (mya)
Lower Ordovician
	Floian	477.7 ± 1.4
	Tremadocian	485.4 ± 1.9
Furongian
	Stage 10	~489.5
	Jiangshanian	~494
	Paibian	~497
Series 3
	Guzhangian	~500.5
	Drumian	~504.5
	Stage 5	~509

Biostratigraphy

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. The still unnamed Cambrian Stage 10 might be defined as the first appearance of Lotagnostus americanus or the conodont Eoconodontus notchpeakensis.

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	Lotagnostus americanus (undecided)
	Jiangshanian	Ellipsocephaloides zone, Saukia zone (lower part)	Agnostotes orientalis
	Paibian	? (?)	Glyptagnostus reticulatus
		Cedaria