Carboniferous

System (period)		Series	Stage (age)	Lower boundary, Ma
Permian		Cisuralian	Asselian	298.9±0.15
Carboniferous	Pennsylvanian	Upper	Gzhelian	303.7±0.1
			Kasimovian	307.0±0.1
		Middle	Moscovian	315.2±0.2
		Lower	Bashkirian	323.2±0.4
	Mississippian	Upper	Serpukhovian	330.9±0.2
		Middle	Visean	346.7±0.4
		Lower	Tournaisian	358.9±0.4
Devonian		Upper	Famennian	older
Subdivisions and "golden spikes" according to IUGS as of September 2023

The Carboniferous is the fifth period (system in stratigraphy) of the Paleozoic era that extends from the end of the Famennian age of the Devonian period, at 358.9 ± 0.4 million years ago, to the beginning of the Asselian age of the Permian period, at 298.9 ± 0.15 Ma. The name Carboniferous means "coal-bearing" and derives from the Latin words carbō (“coal”) and ferō (“I bear, I carry”), and was coined by geologists William Conybeare and William Phillips in 1822. It is characterized by the spreading of vast swampy forests and appearance of the first amniotes. The supercontinent of Pangaea formed during this period.

Definition

The Global Stratotype Section and Point (GSSP) of the Carboniferous system as well as the Mississippian subsystem and the Tournaisian stage was ratified in 1990. The lower boundary was fixed in the section in La Serre, France, and the first appearance of the conodont Siphonodella sulcata is related to it. However, in 2006, it was discovered that the correlation of the type section is problematic.

Carboniferous subdivisions

In International chronostratigraphic chart, Carboniferous system is subdivided into Mississippian and Pennsylvanian subsystems, which were originally used in North American chart. Both subsystems contain three series (geochronological equivalent of series is an epoch): Lower, Middle and Upper, and each of them (except Upper Pennsylvanian) corresponds to a geological stage (geochronological equivalent of stage is an age). Tournaisian, Visean and Serpukhovian are parts of the Mississippian, while Bashkirian, Moscovian, Kasimovian and Gzhelian are parts of the Pennsylvanian. The last two, Kasimovian and Gzhelian, are united into the Upper Pennsylvanian series.

Paleogeography

During the Carboniferous, the southern part of Gondwana was covered with ice masses. This glaciation is known as the Karoo Ice Age

In the first part of the Carboniferous, the supercontinent of Pangaea formed. The southern part of this land mass was covered by ice sheets. This glaciation (known as the late Paleozoic icehouse or the Karoo ice age) was last in the Paleozoic and penultimate in the Phanerozoic.

It is assumed that in the Carboniferous the Earth's atmosphere contained the greatest amount of oxygen, more than 30%.

Carboniferous life

Stigmaria, the Carboniferous tree

After the mass extinction, the rate of reef formation in the seas noticeably decreased and remained so until the Mesozoic. The number of trilobites decreased, and armored fish became completely extinct. In the Carboniferous seas, echinoderms reached a great diversity, and cartilaginous fish became the largest predators.

Carboniferous forest

At the water's edge there was an active evolution of plants and animals. Primitive seed ferns appeared during the Devonian, but established further in the Carboniferous, as well as the beginning of cycads. In the equatorial region, gigantic swampy forests grew, leaving behind voluminous deposits of coal. In these forests, many centipedes and arachnids appeared. By the late Carboniferous, 27 insect Orders had evolved, many of which were winged. Mandible and sucking mouthparts also evolved here, indicating a diversification of feeding habits in insects. A variety of amphibians flourished in swamp ecosystems. Pholiderpeton reached up to 4.5 m and was likely the largest tetrapod of the time.

During this period, the first amniotes arose, which later became the dominant vertebrates on land. The first sauropsids like the lizard-like Hylonomus were small animals that lived in the forest canopy and hid among the trees from large arthropod predators. Sauropsids include later turtles, lepidosaurs, archosaurs, and therefore birds. This was also the time when the first synapsids were appearing. These were creatures with two postorbital openings. Synapsids would give rise to the various groups in Permian and the first true mammals in the late Triassic.

External links

• A simulation of the Carboniferous can be found here: http://www.extra-life.de