The shape of the relief of the Siberian platform. Minerals of the Siberian platform

The Siberian platform, or. As it is also called, the East Siberian platform, in order to distinguish it from the West Siberian one, is one of the main objects of studying Russian geology. On its territory there are significant deposits of minerals, in addition, the study of its formation and the present state is interesting from a purely scientific standpoint. The subsoil and the shape of the relief of the Siberian platform disturb the minds of more than one generation of scientists. Let's discuss the main issues related to this continental section of the earth's crust.

Geographical location

First of all, let's find out where the foundation of the Siberian platform is located geographically. Its main massif is located in the eastern part of Russian Siberia in the territories of the Siberian and Far Eastern federal districts. In the south the platform reaches the territory of Mongolia.

From the west, its natural boundary is the riverbed of the Yenisei River, in the north - the Byrranga Mountains on the Taimyr Peninsula, the Lena River in the east, the Yablonovoye, Stanovoi, Dzhugdur Ranges, and the Pribaikalsky Fault System.

Geologically, the Siberian Platform is a constituent of the Eurasian lithospheric plate and is located in the north-eastern part of it. In the west it is joined by the West Siberian platform, in the south - by the Ural-Mongolian belt, to the east by the West Pacific belt, and in the north by the waters of the Arctic Ocean, which are hidden most of the year under the ice.

History of Education

Now let's find out how the corresponding form of the relief of the Siberian Platform was formed for millions of years of geological processes.

This continental section of the earth's crust is of the type of ancient platforms, or cratons. Unlike other formations, it was formed in the Precambrian period, which implies a minimum age of such formations of 541 million years. They served as the basis for the formation of the continents, becoming their core.

The Siberian platform belongs to the Lavrazian type. This means that in the Mesozoic era, it was part of the continent of Laurasia. But much earlier than this period began to form the ancient Siberian platform. The form of the relief began to be outlined in the Archean era, that is, no later than 2.5 billion years ago. However, at that time it was slightly reminiscent of the modern one. The formation of the foundation was completed at the beginning of the Proterozoic era, at the end of which the platform was covered with a shallow sea, which significantly influenced the formation of the sedimentary cover. In the late Ordovician in the platform was the continent of Angarida. Later, he and the other continents of the Earth merged into a single continent - Pangea. In the Mesozoic, as mentioned above, the Siberian Platform, together with the West Siberian Plate and the East European Platform, after the separation of Pangea, formed the continent of Laurasia. After its disintegration, the Siberian Platform became part of Eurasia.

This is how the Siberian platform was formed approximately.

Structure

The structure of the Siberian platform is similar to the structure of all other ancient platforms. At its base is the foundation, formed even in the Archean and at the beginning of the Proterozoic era. Above the basement covers the sedimentary cover of rocks, formed in later eras, mainly being a product of magmatic activity. This is due to the fact that in antiquity it was a region with high volcanic activity, and magma, which emerged from the bowels of the earth, formed a cover from the trap. But in two places the foundation of the platform still comes to the surface. The output of Precambrian rocks on the surface is commonly called shields.

Shields consist of three complexes of rocks: greenstone, granular belts, as well as a complex of para- and orthogneisses.

Shields of the Siberian platform

On the territory of the Siberian platform there are two shields - Anabar and Aldan.

Aldan is located in the south-eastern part of the platform. In geography this place is called the Aldan Mountains.

The Anabar Shield is much smaller in size and is located in the northern part of the platform on the territory of the Central Siberian Plateau, in a place known as the Anabar Plateau. Its maximum height above sea level is 905 meters.

The Central Siberian Plateau

Now let's see what the modern relief of the Siberian platform looks like.

The main part of the territory is occupied by the Central Siberian plateau. There is alternation of low ridges and plateaus. The highest point of the plateau is Mount Kamen. It is located on the middle reaches of Putorana and has a height of 1701 meters above sea level. But the average height of the Central Siberian plateau is only 500-800 meters. In addition, on this plateau should be allocated Anabar plateau, which we mentioned just above. It represents the protrusion of the Anabar Shield on the surface. The highest point of this plateau is 905 meters above sea level.

In the west, the plateau surrounds the Yenisei Ridge, which simultaneously serves as the boundary for both it and the Siberian Platform as a whole. Its average height is 900 meters above sea level, but it reaches a maximum on Mount Enashimsky Polkan and is 1104 m. Behind the Yenisei Range lies the West Siberian platform.

In the south and southeast, the border of the Central Siberian plateau is the Angara Ridge. The average height is from 700 to 1000 meters above sea level, the maximum height is 1022 m.

In the east and north-east, the Central Siberian plateau, and hence the corresponding form of the relief of the Siberian platform, smoothly passes into the Central Yakut plain. In another way, it is also called the Central Yakutia, or the Lena-Vilui lowland. In most of its territory, the maximum height above sea level does not exceed 100-200 m, but on the outskirts can reach 400 meters.

The shape of the relief of the Siberian platform on the interior watersheds is rather flattened. Therefore, the height of these watersheds does not exceed 400-600 meters. In particular, this statement refers to the boundaries of the basins of the Angara, Nizhny Vilyuy and Tunguska rivers .

Other elements of the relief of the Siberian platform

In the south-east of the Central Siberian plateau lies the Aldan Highlands. Unlike the above objects, it is not part of the plateau, but, nevertheless, it is part of the Siberian platform, representing an exit to the surface of its crystalline shield. It is on the territory of the Aldan Plateau that the highest point of the Siberian platform is located, reaching an altitude of 2,306 meters above sea level. But most of the highland has a height not exceeding a thousand meters.

The shape of the relief of the Siberian platform in the extreme southeast has a mountainous character. Here, in the territory of the Khabarovsk Territory, the Dzhugzhugur mountains are located. Although the average height of this complex is higher than the Aldan Highlands, the highest peak of Topko is inferior in size to the highest point of the highlands. Mount Topko has a height of only 1906 meters above sea level. The length of the Dzhugdzhugur mountains from the north-east to the south-west along the coast of the Sea of Okhotsk is 700 kilometers.

So, we have in general learned what the shape of the Siberian Platform is.

Hydrography

Now let us dwell on the main water bodies of the Siberian platform. As a rule, their initial location directly depended on the relief, and only afterwards, after its occurrence, rivers and lakes, which in the region are in fairly large numbers, themselves begin to influence the formation of the terrain.

The largest water artery, the Yenisei, is the natural western boundary of the Siberian platform. It is one of the largest rivers in the world, the length of which is 3487 meters.

To a large extent, the boundary of the Siberian platform, only in the east, is another large river - Lena. Although in part it carries its waters directly over the platform territory. Its length is 4400 km.

In the south, the Siberian platform on a small area adjoins the deepest lake in the world - Lake Baikal.

Among other large waterways flowing along the Siberian platform, it is necessary to distinguish the Angara, Nizhny Vilyui and Tunguska rivers.

Minerals of the southern part of the Siberian platform

Now we need to study the minerals of the Siberian platform. It should be noted that the mother-nature endowed them with the region in considerable quantities. What are the subsoil of the East Siberian platform?

The Aldan Shield is a real storehouse of iron ore. In addition, the Aldan plateau also produces copper, coal, mica and even gold.

But the largest reserves of gold and diamonds are located in the territory of Yakutia, which is a real treasury of Russia. In the same republic, a "combustible stone" is mined on the territory of the Lena Coal Basin.

In addition, the extraction of coal takes place in the bowels of the Tunguska and Irkutsk basins, which are located in the territories of Yakutia, the Krasnoyarsk Territory and the Irkutsk Region.

Minerals of the north of the Siberian platform

The minerals of the Siberian Platform in its northern part are mainly concentrated in the territory of the Anabar Shield. There are deposits of apatites, anorthosites, titanomagnetites. Copper and nickel mined near Norilsk.

But for oil and gas, in comparison with the areas of Western Siberia, the territory of the East Siberian platform is poor. Although there are oil fields in the south and north, but in much smaller volumes.

Soils

The top layer covering the area of the Siberian platform is the soil. Let us consider what species they represent in the region under study.

Considering that most of the Siberian platform is covered by taiga, the soils formed here correspond to this natural zone. In the north - it is frozen-taiga, to the south - sod-forest. In the south, considerable areas are occupied by sod-podzolic soils, sometimes gray forest and even chernozems occur. Only the last type of soil of all the above is distinguished by high fertility.

General characteristics of the Siberian platform

As you can see, the Siberian platform is one of the oldest geological formations on Earth. The relief in most of the territory is represented by plateaus, and only along the borders the platform is framed by comparatively low mountains or hills.

The region is very rich in various minerals. Among them, iron ore, coal, apatite, gold and diamonds should be distinguished. There is oil, although this is not the main indicator of the region's wealth. But the soil on the platform is not characterized by high fertility.