What Continents Exist

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What Continents Exist
What Continents Exist

Video: What Continents Exist

Video: What Continents Exist
Video: How many continents are there? 2024, March
Anonim

The mainland, or continent, is a fairly large massif of the earth's crust, most of which protrudes above the surface of the World Ocean. In the modern geological era, there are six continents: North America, South America, Eurasia, Antarctica, Africa and Australia.

What continents exist
What continents exist

How the continents appeared

About 250 million years ago, there was only one continent on planet Earth - Pangea. Its area was about the same as that of all modern continents combined. Pangea was washed by an ocean called Panthalassa. He occupied the rest of the space on the planet. Since then, the number of oceans and continents has changed.

About 200 million years ago, Pangea was split into two continents: Gondwana and Laurasia, between which the Tetris Ocean was formed. Now in its place are the deep-water parts of the Black, Mediterranean and Caspian Seas, as well as the shallow Persian Gulf.

Later, Gondwana and Laurasia split into several parts. At first, a piece of land was isolated from the first mainland, which now constitutes Antarctica and Australia. The rest of Gondwana split into several small plates, the largest of which are present-day Africa and South America, and these continents are now diverging from each other at a rate of 2 cm per year.

The faults also covered the second continent. Laurasia split into two plates - today's Eurasia and North America. The emergence of Eurasia is considered by many scientists to be the greatest cataclysm of the planet. Unlike other continents, which are based on one fragment of the most ancient continent, Eurasia includes three lithospheric plates at once. Approaching each other, they almost completely destroyed the Tetris ocean. It is noteworthy that Africa is also taking part in shaping the image of Eurasia. Its lithospheric plate is slowly but surely approaching the Eurasian plate. The result of this convergence is the mountains: Alps, Pyrenees, Carpathians, Ore Mountains and Sudetes. Also, the activity of the Etna and Vesuvius volcanoes reminds of this.

The struggle between continents and oceans has been going on for hundreds of millions of years. Every mountain range, deepest oceanic depression, island arc is the result of this struggle.

Interesting facts about the continents of the Earth

The total area of all continents of the Earth is 139 million km2. They are all fairly isolated from each other. The location of the continents, as well as the differences in the system of tides and currents, the properties of the waters, makes it possible to divide the World Ocean into separate parts, called oceans. There are four of them: Atlantic, Pacific, Indian, Arctic.

Eurasia is the largest continent on the Earth. It occupies one third of the entire land mass of the planet. Almost 5 billion people live on the territory of Eurasia, which is three quarters of the world's population.

The smallest mainland is Australia. Unlike other continents, it is entirely located in one hemisphere - the Southern. Almost in the middle, Australia is crossed by the Southern Tropic, so its southern part is in temperate, and the northern part is in a hot zone of illumination. In addition, this continent is considered the lowest and flattest. There is not a single active volcano on it, and there are no earthquakes in Australia either.

Antarctica is considered the highest continent. Its average height is 2200 m, which is 2.5 times the average height of Eurasia. Antarctica accounts for 90% of the planet's ice. Due to the special weather conditions, the sun on this continent has a greenish tint at sunset. The Great Barrier Reef stretches along its northeastern coast, which is unmatched.

Africa is the second largest continent on Earth. Its geographic highlight lies in the fact that it is located almost symmetrically in relation to the equator.

The third largest continent is North America, which covers an area of just over 24 million km2. But this continent has the longest coastline. Its length is 75.6 thousand km.

South America is a continent with an abundance of geographical records. Here is the highest peak of the southern and western hemisphere, and also the highest extinct volcano - Mount Aconcagua, the world's longest mountain range - the Andes, the largest lowland - the Amazon, the highest lake - Titicaca, the most full-flowing river on the planet - the Amazon, the most high active volcano - Llullaillaco.

The mainland and parts of the world: what is the difference

The entire land of the Earth is conventionally divided into continents and parts of the world. Many people confuse these concepts, which is wrong. If part of the world is a historical and cultural concept that was introduced by people, then the existence of continents is an objective reality that has developed as a result of the movement of lithospheric plates. There are also six parts of the world: Europe, America, Asia, Australia and Oceania, Africa and Antarctica. Part of the world includes not only the mainland, but also the islands adjacent to it.

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