Old Earth Ministries Online Earth History Curriculum
Presented by Old Earth Ministries (We Believe in an Old Earth...and God!)
This curriculum is presented free of charge for use by homeschooling families.
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Chapter 7 - The Carboniferous Period
Lesson 36: Carboniferous Overview
The Carboniferous is a
geologic period and system that extends from the end of the Devonian period,
about 359.2 ± 2.5 Ma (million years ago), to the beginning of the Permian
period, about 299.0 ± 0.8 Ma, with a total duration of about 60.2 million
In the USA the Carboniferous is usually broken into Mississippian (earlier) and Pennsylvanian (later) Epochs. The Mississippian is about twice as long as the Pennsylvanian, but due to the large thickness of coal bearing deposits with Pennsylvanian ages in Europe and North America, the two subperiods were long thought to have been more or less equal.
Chapter 7 - The Carboniferous Period
Carboniferous Fast Facts
The early part of the Carboniferous was mostly warm; in the later part of the Carboniferous, the climate cooled. Glaciations in Gondwana, triggered by Gondwana's southward movement, continued into the Permian and because of the lack of clear markers and breaks, the deposits of this glacial period are often referred to as Permo-Carboniferous in age.
A global drop in sea level at the end of the Devonian reversed early in the Carboniferous; this created the widespread epicontinental seas and carbonate deposition of the Mississippian. There was also a drop in south polar temperatures; southern Gondwanaland was glaciated throughout the period, though it is uncertain if the ice sheets were a holdover from the Devonian or not. These conditions apparently had little effect in the deep tropics, where lush coal swamps flourished within 30 degrees of the northernmost glaciers.
A mid-Carboniferous drop in sea-level precipitated a major marine extinction, one that hit crinoids and ammonites especially hard. This sea-level drop and the associated unconformity in North America separate the Mississippian period from the Pennsylvanian period. This happened about 320 million years ago, at the onset of the Permo-Carboniferous Glaciation.
The Carboniferous was a time of active mountain-building, as the supercontinent
There were two major oceans in the Carboniferous—Panthalassa and Paleo-Tethys, which was inside the "O" in the Carboniferous Pangaea. Other minor oceans were shrinking and eventually closed - Rheic Ocean (closed by the assembly of South and North America), the small, shallow Ural Ocean (which was closed by the collision of Baltica and Siberia continents, creating the Ural Mountains) and Proto-Tethys Ocean (closed by North China collision with Siberia/Kazakhstania).
Rocks and Coal
Carboniferous rocks in Europe and eastern North America largely consist of a repeated sequence of limestone, sandstone, shale and coal beds, known as "cyclothems" in the U.S. and "coal measures" in Britain. In North America, the early Carboniferous is largely marine limestone, which accounts for the division of the Carboniferous into two periods in North American schemes. The Carboniferous coal beds provided much of the fuel for power generation during the Industrial Revolution and are still of great economic importance.
In eastern North America, marine beds are more common in the older part of the period than the later part and are almost entirely absent by the late Carboniferous. More diverse geology existed elsewhere, of course. Marine life is especially rich in crinoids and other echinoderms. Brachiopods were abundant. Trilobites became quite uncommon. On land, large and diverse plant populations existed. Land vertebrates included large amphibians.
Life in the Carboniferous
Although Earth's poles
were covered by ice caps, the
equatorial regions of the planet were dominated by vast
lands during most of the Carboniferous. Early Carboniferous
land plants were very similar to those of the preceding Late
Devonian, but new groups also appeared at
The main Early Carboniferous plants were the
Lycopodiales (Club mosses),
Lepidodendrales (scale trees),
(informally included in the "seed
ferns", an artificial assemblage of a number
gymnosperm groups) and
continued to dominate throughout the period, but during
late Carboniferous, several other groups,
(another group of "seed ferns"), and the
Voltziales (related to
and sometimes included under the
Sponges are known from
and anchor ropes, and include various forms such as the
Girtycoelia, and the
genus of unusual colonial
bony fish, the
in coastal waters also appear to have migrated to rivers.
Sarcopterygian fish were also prominent, and
one group, the
very large size.
giant dragonfly-like insect
Meganeura grew to wingspans of 75 cm.
Pulmonoscorpius from the early Carboniferous
reached a length of up to one meter.
amphibians were diverse
and common by the middle of the period, more so than they are today; some
were as long as 6 meters, and those fully terrestrial as adults had scaly
They included a number of basal tetrapod groups classified in early books
had long bodies, a head covered with bony plates and generally weak or
undeveloped limbs. The largest were over 2 meters long. They were
accompanied by an assemblage of smaller amphibians included under the
Lepospondyli, often only about 15 cm long.
Some Carboniferous amphibians were aquatic and lived in rivers, while others may have been
semi-aquatic or terrestrial.
End of Reading
Source - Wikipedia - The Carboniferous