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What is the lithosphere?

The core, the mantle and the bark are the internal structure of the Earth. And what is the lithosphere? This is the name for the outer solid inorganic shell of our planet. It includes the entire earth's crust and the upper part of the mantle.

What is the lithosphere
In a simplified form, the lithosphere is aThe upper layer of the Earth, consisting of three layers. In the scientific world there is no unambiguous definition of the concept of this planetary shell. And about its composition, disputes are also continuing. But according to available information, all the same you can make basic ideas about what the lithosphere is.

Structure, composition and boundaries

Despite the fact that the lithosphere coversabsolutely the entire earth's surface and the upper layer of the mantle, in weight equivalent it is expressed only in one percent of the total mass of our planet. Although the shell has small volumes, its detailed study has caused a lot of questions, and not only what is the lithosphere, but also what material it is formed from, in what state it is in different parts.

The main part of the shell consists of hard rocks, which on the border with the mantle acquire a plastic consistency. The structure of the earth's crust is distinguished by stable platforms and areas of folding.

Earth's lithosphere

The crust has a different thickness and canfluctuate from 25 to 200 kilometers. On the ocean floor, it is thinner - from 5 to 100 kilometers. The Earth's lithosphere is bounded by other shells: the hydrosphere (water) and the atmosphere (air).

The crust is composed of three layers:

  • sedimentary;
  • granite;
  • basaltic.

Thus, if we look at what islithosphere in the section, it will resemble a layered pie. Its basis is basalt, and on top it is covered with a sedimentary layer. Between them, in the form of a filling, is granite.

The sedimentary layer on the continents was formed inthe result of the destruction and modification of granite and basalt rocks. On the ocean floor, this stratification is formed as a result of the accumulation of sedimentary rocks carried out by rivers from the continents.

The granite layer consists of metamorphic andigneous rocks. On the continents, it occupies an intermediate position between other layers, and on the ocean floor it is completely absent. It is believed that in the very heart of the planet there is a basalt consisting of magmatic rocks.

The Earth's crust is not a monolith, it consists of separate blocks, called lithospheric plates, which are in constant motion. They seem to float on the plastic asthenosphere.

Ecological problems of the lithosphere
Ecological problems of the lithosphere

During its existence, mankind haseconomic activity constantly used the constituent parts of the lithosphere. The earth's crust contains all the mineral resources that are widely used by people, and their extraction from the bowels is constantly increasing.

Of great value is the soil - the preservation of the fertile layer of the lithosphere today is one of the most urgent problems that require immediate resolution.

Some processes occurring within the boundariesshells, for example, erosion, collapses, mudslides, can be caused by anthropogenic activity and pose a threat. They not only affect the formation of environmental situations in certain areas, but can also lead to global environmental disasters.

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