[Map of Pangea North and South China locations are depicted quite variable, suggested evidence]

Over 300 million years ago in the Early Permian Epoch, the Earth had one supermassive ocean, called Panthalassa, and one supermassive continent called, Pangea. A supermassive continent is a continent comprised of multiple continents. Pangea, was a supercontinent made from all of the continents of the world.

Pangea, is one of the Earth’s old supercontinents that was created over 3.5 billion years ago. Supercontinents have been formed over the years due to the Earth’s tectonic plates sliding over its mantle. The process breaks up landmasses and builds new landmasses. It has been suggested that continents on these tectonic plates currently move at the same rate as the average human’s fingernails grow.

Where did the name Pangea come from?

Pangea is actually derived from a Greek word, meaning “all lands.” Pangea was first used in the early 20th century by Alfred Lothar Wegener, who was a German polar researcher, geophysicist, and meteorologist. While researching the Earth’s continents, he noticed that the continents seemed to fit together like a jigsaw puzzle. Later he came up with the theory of continental drift, this explained why the Earth’s continents are shaped the way they are. Leading to the title of Pangea for the supercontinent, he proposed the name Pangea at a symposium in 1927, now this theory has evolved to the modern study of plate tectonics.

How was Pangea formed?

Pangea was formed via landmass formation and movement over time. Mantle convection, which is, the upwards motion of Earth’s solid silicate mantle (a rocky material with an average thickness of 2,886 kilometers (1,793 mi) caused by convection currents which carry heat from the Earth’s core to the planet’s surface. The Earth’s surface lithosphere rides atop the asthenosphere, these two combined, create the upper mantle (just beneath the crust and ends at the top of the lower mantle). Thus, creating new material to rise to the Earth’s surface. This material rises between the Earth’s tectonic plates, through cracks which are called rift zones. These landmasses, or continents then moved away from the rifts as more new material surfaced from the Earth’s core. Thus, the continents moved gradually towards each other, creating a supercontinent, this was how Pangea was formed.

How did these landmasses / continents join together?

The landmasses or continents joined together to form Pangea through migration and collision. This migration and collision took part around 300 million years ago, when the northwestern part of Gondwana, an ancient continent located near the South pole, joined with the southern Euramerican continent via a collision. This formed a massive continent. Following this new massive continent creation, the Angaran continent (located near the North Pole) started to move south and joined with the northern part of the newly formed massive continent. This then formed the supercontinent called Pangea. The creation of Pangea was finalised around 270 million years ago.

After the creation of Pangea, there was a total of two landmasses/continent’s, the second was Cathaysia, which was north and south China. Once Pangea was completely formed, the supercontinent covered around one third of the Earth’s surface. While the Cathaysia, and the ocean covered the rest, the ocean was called Panthalassa.

How Pangea divided

Around 200 million years Pangea started to divide, the divide was quite close to how it was formed, via tectonic plate movement, associated with mantle convection. Like the way Pangea was formed via new material being transported to the Earth’s surface through rift zones, the new material also caused Pangea to separate. Researchers have suggested that the cause of Pangea’s separation was caused by a weakness in the Earth’s crust. Within this weak area of the Earth’s crust, magma surfaced and a volcanic rift zone was developed. The volcanic rift zone eventually grew in size until it formed a basin, and Pangea started to divide.

New ocean formation

As the supercontinent of Pangea divided the Panthalassa ocean covered newly opened areas. Of the new oceans, the Atlantic was the first. Around 180 million years ago North America, and northwestern Africa saw part of the Atlantic Ocean open up. 140 million years ago, saw the formation of the South Atlantic, this was via, South America dividing from the west coast of southern Africa.

When India, Antartica, and Australia divided, the Indian Ocean was created this was around 100 million years ago. And lastly, around 80 million years ago saw the detachment of, Australia and Antarctica, America and Europe, and India and Madagascar. And it has taken millions of more years to see the continents placed where they are today.

More information can be found here: Dynamic Earth

Alfred Wegener continental drift theory

Alfred Wegener, the creator of the continental drift theory, while studying the earth, noticed that the Earth’s continents almost fitted together like a jigsaw puzzle. The most prominent place that this can be seen is along the northwestern coast of Africa, and also the eastern coast of South America. It has been suggested these observations provide some evidence that the continents were all connected, and this work by Alfred Wegener is his most famous.

Fossil Distribution

Other suggestions to backup the Pangea theory are that fossils which match have been found in continents separated by thousands of miles. An example of these matching fossils are, matching freshwater reptile fossils found in Africa and South America. These continents are suggested to of been connected, as it would of been impossible for these creatures to cross the ocean, thus leaving suggesti8ve evidence that the supercontinent of Pangea did exist.

Rock patterns in strata

More supportive evidence that Pangea did exist is the rock patterns in strata, Geologists have been finding matching patterns on rocks in different continents, miles away from each other. The patterns of the rock layers appear to of once fit together as they match each other exactly. This may indicate that the continents did once fit together.

Coal locations

It is normal for coal to form in dry wet climates. But, more recently scientist have found coal under Antarctica’s dry ice caps. As coal can not be formed in cold locations, scientists have suggested that Antarctica was once in another location, and this location had a warmer climate, which was able to support coal formation.

Other supercontinents

It has been suggested that more supercontinents existed on Earth, before Pangea supposedly existed. It has been suggested through scientists’ research that other supercontinents existed. This has been proposed by the analysis of matching rock formations, and fossils. Science have approved the theory of two more supercontinents prior to Pangia, namely, Godwana, and Rodinia.

It has been suggested by researchers that supercontinents will continue to form over the years. With today’s world continues moving away from the mid-Atlantic Ridge toward the central Pacific Ocean. And they have been suggested to collide in around 80 million years.

Video relating to Pangea, National Geographic

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References