Gzhelian

Gzhelian
303.7 ± 0.1 – 298.9 ± 0.15 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type locality for the Gzhelian in Gzhel, Russia
Chronology
−360 — – −355 — – −350 — – −345 — – −340 — – −335 — – −330 — – −325 — – −320 — – −315 — – −310 — – −305 — – −300 — – Paleozoic D Carboniferous P Mississippian Pennsylvanian LD Early Middle Late Early Mid Late CS Famennian Tournaisian Viséan Serpukhovian Bashkirian Moscovian Kasimovian Gzhelian Asselian     ← Carboniferous Rainforest Collapse ← Mazon Creek Fossils ← End of Romer's Gap ← Start of Romer's Gap Subdivision of the Carboniferous according to the ICS, as of 2021.[1] Vertical axis scale: millions of years ago
Etymology
Name formality	Formal
Usage information
Celestial body	Earth
Regional usage	Global (ICS)
Time scale(s) used	ICS Time Scale
Definition
Chronological unit	Age
Stratigraphic unit	Stage
Time span formality	Formal
Type section	Gzhel horizon, Ghzel, Moscow Oblast, Russia
Lower boundary definition	Not formally defined
Lower boundary definition candidates	FAD of the Conodont Idiognathodus simulator[2]
Lower boundary GSSP candidate section(s)	Southern Ural Mountains[2] Nashui, Luodian County, Guizhou, China
Upper boundary definition	FAD of the Conodont Streptognathodus isolatus within the morphotype Streptognathodus wabaunsensis chronocline
Upper boundary GSSP	Aidaralash, Ural Mountains, Kazakhstan 50°14′45″N 57°53′29″E / 50.2458°N 57.8914°E / 50.2458; 57.8914
Upper GSSP ratified	1996[3]

The Gzhelian (/ˈʒɛli.ən/ ZHELL-ee-ən) is an age in the ICS geologic time scale or a stage in the stratigraphic column. It is the youngest stage of the Pennsylvanian, the youngest subsystem of the Carboniferous. The Gzhelian lasted from 303.7 to 298.9 Ma.^[4] It follows the Kasimovian age/stage and is followed by the Asselian age/stage, the oldest subdivision of the Permian system.

The Gzhelian is more or less coeval with the Stephanian Stage of the regional stratigraphy of Europe.