What is the main element that makes up the earth's crust?

For those people who listened inattentively to the teacher at school, it will be interesting to know that the main element making up the earth's crust is oxygen.

Earth's crust, its features

The two main types of the earth's crust are continental and oceanic. From the names it is clear by what principle they are divided. They differ in composition, structure and other characteristics.

The layers of the earth's crust in the oceanic regions are as follows:

• Sedimentary, which covers the ocean floor (the thickness of the layer is from several meters to two kilometers);
• Basaltic, formed due to the crystallization of magma, which leaves magmatic chambers (thickness - from 4 to 10 kilometers);
• Gabbro-serpentinite, separating the earth's crust from the mantle (5-6 kilometers).

It is interesting that earlier the oceanic crust was separated only into the first two layers, but after carrying out geological studies, the scientists also identified the third layer.

Layers of the earth's crust in continental regions:

• Sedimentary (thickness - up to 15 kilometers);
• Granite (from 15 to 50 kilometers);
• Basaltic (15-20 kilometers).

The continental crust has a much greater thickness (that is, thickness) than the oceanic crust, because it rises above sea level, and in mountain regions in general it considerably exceeds the oceanic crust in capacity.

The chemical composition of the earth's crust

As already mentioned above, the main element that makes up the earth's crust is oxygen. Naturally, it is not present in pure form, but acts as compounds with other chemical elements that make up this composition, and in this form its proportion is more than 49 percent.

The composition of the earth's crust is called aluminosilicate, according to aluminum compounds (the 13th element in the periodic table of chemical elements) and silicon (silicide is in the periodic table element with atomic number 14) with oxygen. In the oceanic crust, the percentage of SiO ₂ content is 61.9, when in the continental layer it is 49.4, and the Al ₂ O ₃ aluminum compound content is almost identical - 15.6% and 16%, respectively. Other elements, such as calcium, magnesium, ferrum, titanium, sodium, potassium, manganese, which also oxidize the main element constituting the earth's crust, occupy fractions from 0.1 to 5.7 percent.

What kind of knowledge in the study of the Earth's crust is given by school science geography

The Earth's crust in the learning process is considered in the context of what the planet Earth consists of, that is, the central inner ball-the core, the mantle and, in fact, the earth's crust, consisting of lithospheric plates moving at a low speed (up to 10 centimeters in Year) on the mantle. The Canadian geophysicist once gave an interesting comparison. He said that the Earth is similar to an egg brewed "in a bag," that is, not hard-boiled.

The structure of the earth's crust (class 7, by the way, more thoroughly and thoroughly examines the topic than the sixth program) is studied on the basis of textbooks that do not always keep pace with new discoveries and changes in the structure of the Earth's objects. But the basic concepts are introduced quite easily and correctly.

Surprises from the Earth

Do not think that once the movement of the strata of the earth's crust is so insignificant - only 10 centimeters per year, then there are no dangers to human life. On the contrary, the activity hidden under the earth's crust is very active and powerful. It is about earthquakes and explosions of volcanoes.

In some sources it is indicated that in the year around the planet there are about five hundred thousand earthquakes of different power. The greatest activity is seen around the Pacific plate.

What to do with this natural disaster?

It is impossible to prevent an earthquake. The forces that provoke this disaster are beyond the control of man, for their source is much deeper than mankind could penetrate. We only "pick" the top layer (for now within 13 kilometers), while the deepest recorded location of the epicenter of the earthquake was 750 kilometers.

But everything was done to foresee the possible disaster, its strength and place. Seismographs are used for this.

Constant research makes it possible to compile a picture of seismic activity and take it into account in construction. Engineers, in turn, are working on new designs capable of withstanding such activity. Constant work is being done to inform the public about how to behave in the event of an earthquake.

The terrible phenomenon that can arise from such a disaster is a tsunami. So, in 2011, huge waves of ocean water ravaged the lands of North-East Japan, resulting in the death of about 16,000 people, and more than a million buildings were destroyed in whole or in part. Including three reactors at the nuclear power plant "Fukushima-1." Over three hundred thousand people were left without a roof over their heads. The same event affected the Earth's rotation speed, but this is unlikely to be noticeable for a person, since the day was the shortest by 1.8 microseconds. So, having touched upon the topic, which is the main element constituting the earth's crust, we have moved on to problems that may arise from the processes hidden by it.