Westphalian (stage)

System	Series (NW Europe)	Stage (NW Europe)	Series (ICS)	Stage (ICS)	Age (Ma)
Permian					younger
Carboniferous	Silesian	Stephanian	Pennsylvanian	Gzhelian	299–303,9
		Westphalian		Kasimovian	303,9–306,5
				Moscovian	306,5–311,7
				Bashkirian	311,7–318,1
		Namurian
			Mississippian	Serpukhovian	318,1–326,4
	Dinantian	Visean		Visean	326,4–345,3
		Tournaisian		Tournaisian	345,3–359,2
Devonian					older
Subdivisions of the Carboniferous system in Europe compared with the official ICS-stages.

The Westphalian is a stage in the regional stratigraphy of northwest Europe with an age between roughly 313 and 304 Ma (million years ago). It is a subdivision of the Carboniferous system or period and the regional Silesian series. The Westphalian is named for the region of Westphalia in western Germany where strata of this age occur. The Coal Measures of England and Wales are also largely of Westphalian age though they also extend into the succeeding Stephanian.

The Westphalian age is preceded by the Namurian stage/age (which corresponds to the Millstone Grit Series of Great Britain) and succeeded by the Stephanian stage/age (which corresponds to the uppermost part of the Coal Measures of Great Britain). In the official geologic timescale of the ICS, the Westphalian is placed within the Pennsylvanian epoch (318-299 Ma).^[1]

The (regionally defined) Westphalian stage corresponds to the upper part of the (internationally used) Bashkirian stage together with the whole of the Moscovian and Kasimovian stages. Frequent references appear in scientific literature to a Westphalian epoch or Westphalian series reflecting the stage's earlier status.

Life

Amphibians were diverse and dominated communities. The collapse of the rainforest ecology between the Moscovian and Kasimovian removed many amphibian species who did not survive as well in the cooler, drier conditions. Reptiles, however prospered due to specific key adaptations and underwent a major evolutionary radiation, in response to the drier climate that proceeded the rainforest collapse.^[2][3]

References

1. F M Gradstein, J G Ogg, A G Smith et al 2004, ‘A Geologic Time Scale 2004’.
2. Sahney, S., Benton, M.J. & Falcon-Lang, H.J. (2010). "Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica" (PDF). Geology 38 (12): 1079–1082. doi:10.1130/G31182.1.
3. M. Alan Kazlev (1998) The Carboniferous Period of the Paleozoic Era: 299 to 359 million years ago, Palaeos.org, Retrieved on 2008-06-23

Preceded by Proterozoic Eon	Phanerozoic Eon
	Paleozoic Era						Mesozoic Era			Cenozoic Era
	Cambrian	Ordovician	Silurian	Devonian	Carboniferous	Permian	Triassic	Jurassic	Cretaceous	Paleogene	Neogene	4ry