The structure of the planet: the Earth's core, the mantle, the earth's crust

The composition of the deep shells of the Earth continues to be one of the most intriguing issues in modern science, and yet at the beginning of the 20th century seismologists Beno Gutenberg and G. Jefferson developed a model of the internal structure of our planet, according to which the Earth consists of the following layers:

- core;
- mantle;
- Earth's crust.

Modern view of the inner structure of the planet

In the middle of the last century on the basis of the last at that time seismological data, scientists came to the conclusion that the deep shells have a more complex device. Then the seismologists found out that the earth's core is divided into internal and external, and the mantle consists of two layers: the upper and lower layers.

Outer shell of the earth

The Earth's crust is not only the uppermost, the thinnest, but also the most well-studied of all layers of the earth's surface. Its thickness (power) reaches the maximum mark under the mountains (about 70 km) and the minimum - under the waters of the world ocean (5-10 km), the average thickness of the earth's crust under the plains ranges from 35 to 40 km. The transition from the earth's crust to the mantle is called the boundary of Mohorovich or Moho.

It should also be noted that the earth's crust, together with the upper part of the mantle, form the stone shell of the Earth - the lithosphere, whose thickness varies from 50 to 200 km.

Following the lithosphere is the asthenosphere - a softened liquid layer with increased viscosity. In addition, it is this component of the earth's surface that is called the source of volcanism, since it contains the centers of magma pouring out into the earth's crust and to the surface.

In science, it is customary to distinguish several types of crust

The continental or continental spreads within the boundaries of continents and shelves, consists of basaltic, granite-geysovogo and sedimentary layers. The transition of the granitic-heisic layer to the basaltic layer is called the Conrad boundary.

Oceanic also consists of three parts: a heavy basalt, a layer of basaltic lavas and dense sedimentary rocks and a layer of loose sedimentary rocks.

The submaric crust is a transitional type located on the periphery of the interior and marginal seas, as well as under island arcs.

The suboceanic crust is similar in structure to the oceanic crust, especially well developed in the deep-water parts of the seas and at great depths of oceanic troughs.

The middle geosphere

The mantle is about 83% of the total volume of the planet, it is the geosphere that surrounds the earth's core from all sides. In turn, it is divided into two layers: solid (crystalline) and soft (magma).

Deep layer of the planet Earth

The Earth's core is the least explored layer of the Earth. Reliable information about it is very small, with complete certainty it can only be said that its diameter is about 7 thousand kilometers. It is believed that the composition of the earth's core includes an alloy of nickel and iron. It should also be noted that the outer core of the planet has a large thickness and is in a liquid aggregate state, while the inner core is smaller in thickness and harder in consistency. From the mantle, the terrestrial core is separated by the so-called Gutenberg boundary.