Cambrian geochronology

The Furongian or Late Cambrian 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 stages: the Paibian, Jiangshanian and the unnamed 10th stage of the Cambrian.

The Paibian is the lowest stage of the Furongian Series of the Cambrian System. The Paibian is also the first age of the Furongian Epoch of the Cambrian Period. It follows the Guzhangian (Miaolingian series of the Cambrian) and is succeeded by the Jiangshanian Stage. The base is defined as the first appearance of the trilobite Glyptagnostus reticulatus around million years ago. The top, or the base of the Jiangshanian is defined as the first appearance of the trilobite Agnostotes orientalis around million years ago.

The Fortunian age marks the beginning of the Phanerozoic Eon, the Paleozoic Era, and the Cambrian Period. It is the first of the two stages of the Terreneuvian series. Its base is defined as the first appearance of the trace fossil Treptichnus pedum million years ago. The top of the Fortunian which is the base of the Stage 2 of the Cambrian has not been formally defined yet, but will correspond to the appearance of an Archeocyatha species or "Small shelly fossils" approximately million years ago.

The Miaolingian or Mid-Late Cambrian 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 preceded by the unnamed Cambrian Series 2 and succeeded by the Furongian series.

The Terreneuvian or Early Cambrian is the lowermost and oldest series of the Cambrian geological system. Its base is defined by the first appearance datum of the trace fossil Treptichnus pedum around million years ago. Its top is defined as the first appearance of trilobites in the stratigraphic record around million years ago. This series' name was formally accepted by the International Commission on Stratigraphy in 2007.

The Wuliuan stage is the fifth stage of the Cambrian, and the first stage of the Miaolingian Series of the Cambrian. It was formally defined by the International Commission on Stratigraphy in 2018. Its base is defined by the first appearance of the trilobite species Oryctocephalus indicus; it ends with the beginning of the Drumian Stage, marked by the first appearance of the trilobite Ptychagnostus atavus around million years ago.

The Jiangshanian is the middle stage of the Furongian series. It follows the Paibian Stage and is succeeded by the still unnamed Stage 10 of the Cambrian. The base is defined as the first appearance of the trilobite Agnostotes orientalis which is estimated to be million years ago. The Jiangshanian lasted until approximately million years ago.

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

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 is defined as the first appearance of another trilobite Lejopyge laevigata around million years ago.

second series and epoch of the Cambrian system and period

second and final stage and age of the 2nd Cambrian series/2nd Cambrian Epoch; fourth of the Cambrian system and period

second and final stage and age of the Terreneuvian series and epoch; second of the Cambrian system and period

first stage and age of the Cambrian Series 2 / Cambrian Epoch 2; third stage of the Cambrian system and period

third and final stage of the Furongian Series; tenth and final stage of the Cambrian Period