The mysteries of the ancient supercontinent of the Earth

Geologists believe that there seems to be a cycle of formation and breaking up the supercontinent after 300 to 400 million years, but the exact reason for this happening so far is still a mystery.

More than a century ago, German scientist Alfred Wegener (1880-1930) proposed the idea of ​​an ancient supercontinent after combining some evidence together. He named it Pangea . The first and most obvious evidence is that the shapes of the continents on both sides of the Atlantic Ocean can fit together (South America and Africa are like two giant pieces), Brendan Murphy, professor of geology at the University of St. Francis Xavier (Canada), said.

Geological records also show that the continents of the Earth previously belonged to a huge land mass. For example, coal mines in Pennsylvania (USA) have the same composition as coal mines of the same age in Poland, England and Germany. This indicates that North America and Europe were once a single land.

In addition, fossils of many identical plant species appear on different continents, such as the Glossopteris fern which has become extinct. The mountains are now located on different continents, such as the Appalachians in the US and the Atlas range in Morocco, both part of Pangea Central Mountains.

Entries - split hundreds of millions of years

The theory of plate tectonics suggests that the Earth's outer crust is divided into many slopes on the mantle (mantle ) layer . During the history of the Earth's 3.5 billion years, some supercontinents have been formed and broken. This is the result of the circulation and physical movement inside the mantle, which accounts for most of the planet's mass. This process has dramatically changed Earth's history.

formed through a process lasting several hundred million years, starting about 480 million years ago. A continent called Laurentia, consisting of a part of North America, merged with several other small continents to form the continent of Euramerica. Euramerica finally collided with Gondwana, another supercontinent including Africa, Australia, South America and the Indian subcontinent, to form the last supercontinent, Pangea.

Pangea supercontinent of the Earth.(Photo: Affirmation Spot).

About 200 million years ago, supercontinent Pangea began to break down. separated from continent Laurasia (Asia-Europe and North America). Then the continent of Gondwana continued to break (India separated from Antarctica, Africa separated from South America). About 60 million years ago, North America separated from the Eurasian continent, according to an article published in the Journal of Geophysical Research.

The current shape of the continents on Earth is not final. The supercontinents have formed many times in the history of the Earth, after which they split into new continents. For example, Australia is now heading towards Asia, the eastern part of Africa is gradually separating from the rest of the continent. Geologists believe that there seems to be a cycle of formation and breaking up of the supercontinent after 300 to 400 million years, but the exact reason for this happening so far is still a mystery, according to Murphy. .

There was abundant life on land

Supercontinent Pangea creates a very different climate cycle. For example, areas deep within the continent may be too dry, as they are blocked by large mountains, all steam or precipitation. However, the existence of many coal mines in the US and Europe shows. The area near the ancient supercontinent's equator Pangaeate is lush tropical rainforest, similar to the current Amazon forest. (Coal forms when the corpses of animals, plants sink into swamp water, where pressure and water convert matter into peat, then coal).

'Coal mines basically tell us that the past has had a plentiful life on land,' Murphy said. Climate models affirm that the deep-lying mainland in supercontinent climate changes seasonally in an extreme way, according to an article published in Palaeogeography, Palaeoclimatology, Palaeoecology in June 2016. Scientists in this study used the physical and biological data of the Moradi Formation - an area containing paleosol ancient soil layers in northern Niger - to reconstruct the ecosystem and climate during Pangea exist.

The results show that the central climate of Pangea is comparable to the Namib Desert (Africa) or today's Lake Eyre Basin (Australia). The climate is generally dry with short, repeating periodic wet periods, sometimes including catastrophic flash floods. Pangea existed for about 100 million years, and during that time a number of animals have thrived, including Traversodontidae - a plant-eating animal family that includes the ancestors of mammals.

About 230 million years ago, some of the first dinosaurs appeared on Pangea, including theropod carnivores with light bones and feathers like birds. However, Pangea's existence coincides with the time of the occurrence. The worst mass extinction event in history, which was the Panermi-Triassic extinction event that occurred about 252 million years ago, made all species on Earth disappear.