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Planet Earth, the composition, structure and layers of the earth

Earth is the third planet from the eight planets in the Solar System. Estimated to reach 4.6 billion year age. The distance between the Earth to the Sun is 149.6 million kilometers or 1 AU (ing: astronomical unit). Earth has a layer of air (atmosphere) and the so-called magnetic field (magnetosphere) that protect Earth's surface from the solar wind, ultraviolet rays, and radiation from outer space. This air layer surrounds the earth to a height of about 700 kilometers. The air layer is divided into Troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

The ozone layer, as high as 50 kilometers, are in the stratosphere and mesosphere and protects the earth from ultraviolet rays. The difference between the earth's surface temperature is -70 ° C to 55 ° C depending on the local climate. The day is divided into 24 hours, and a year on earth equal to 365.2425 days. Earth has a mass weight of 59,760 billion tonnes, with a surface area of ​​510 million square kilometers. The density of the Earth (about 5,500 kilograms per cubic meter) is used as a unit of weight ratio of any other type of planet, the gravity of the Earth is set as 1.

Earth has a diameter of 12,756 kilometers long. Earth's gravity is measured as 10 N kg-1 be a unit of measure of the gravity of other planets, the Earth's gravity is set as 1. Earth has one natural satellite is the moon. 70.8% the earth's surface covered with water. Earth Air consists of 78% nitrogen, 21% oxygen, and 1% water vapor, carbon dioxide, and other gases.

Earth estimated to be made up in the Earth's core consists of iron-nickel-thick frozen 1370 kilometers with temperatures 4500 ° C, is also covered by a liquid outer core that is 2100 kilometers thick, and covered also by the 2800 kilometer-thick mantle of silica to form 83% of the earth, and eventually completely covered by the earth's crust about 85 kilometers thick.

The crust is thinner at the bottom of the sea which is about 5 kilometers. The crust is divided to several parts and moving through the movement of tectonic plates (the theory of continental drift) that produce earthquakes.

The highest point on the earth's surface is as high as Mount Everest at 8,848 meters, and the deepest point is the Mariana trench in the Pacific with a depth of 10,924 meters. Lake Baikal is the deepest lake with a depth of 1637 meters, the largest lake is the Caspian Sea with an area of ​​394,299 km2.

Composition and structure

Earth is a terrestrial planet, which means it is made of rock, different than a gas giant like Jupiter. This planet is the largest of the four terrestrial planets, in both senses, mass and size. Of the four terrestrial planets, Earth also has the highest density, the largest surface gravity, the strongest magnetic field, and fastest rotation. Earth is also the only terrestrial planet with active plate tectonics.

Form

Shape very similar to planet Earth sphere flattened (oblate spheroid), a depressed sphere flat on the orientation of the poles that cause buncitan at the equator. Buncitan This happens because the earth's rotation, causing the equatorial diameter greater than 43 km in diameter from pole to pole. Average diameter of the circle of the earth is 12,742 miles, or about 40,000 km / π. Since the meter was originally defined as the distance between the 1/10.000.000 equator to the North Pole through Paris, France.

Local topography varies slightly from the ideal sphere form a smooth, even on a global scale, the variation is very small. Earth has a tolerance of about one in 584, or 0.17% compared to a perfect sphere (reference spheroid), a more seamless when compared with the tolerance of a billiard ball, 0.22%. Largest local deviations in the surface of the earth is Mount Everest (8,848 m above sea level) and the Mariana Trench (10,911 m below sea level). Because buncitan equator, the earth is farthest away from the midpoint of the Earth is actually Mount Chimborazo in Ecuador.

Endogenous natural processes / endogenous labor force of the earth is from the earth. Workers are building the endogenous nature of the earth's surface. Exogenous natural forces of extraterrestrial origin and destructive. So the two energy that makes a wide range of relief on the face of this earth as we know that the surface of the earth we inhabit is composed of various formations such as mountains, valleys, hills, lakes, rivers, etc.. The existence of these formations, causing the earth's surface becomes uneven. Formations are known as the relief of the earth.

The chemical composition
F. W. Clarke's Table oxide scale
Compound Formula Composition
Silica SiO2 59.71%
alumina Al2O3 15.41%
lime CaO 4.90%
Magnesia MgO 4.36%
sodium oxide Na2O 3.55%
iron (II) oxide FeO 3.52%
potassium oxide K2O 2.80%
iron (III) oxide Fe2O3 2.63%
Water H2O 1.52%
titanium dioxide TiO2 0.60%
phosphorus 0.22% P2O5 pentoxida
Total 99.22%

The mass of the Earth is approximately 5.98 × 1024 kg. The content is primarily of iron (32.1%), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%) , calcium (1.5%), and aluminum (1.4%), and the remaining 1.2% consists of various rare elements. Because the process of mass segregation, the core of the earth is believed to have the main content of iron (88.8%), and a small amount of nickel (5.8%), sulfur (4.5%), and the rest less than 1% of rare elements. [10]

Geochemist F. W. Clarke calculated that about 47% of the earth's crust consists of oxygen. The most common rocks in the crust contained almost all of them are oxides (oxides), chlorine, sulfur and fluorine are an exception and the number is on the rocks is usually less than 1%. Principal oxides are silica, alumina, iron oxide, lime, magnesia, potash and soda. The main function is as an acid silica, forming silicates. It is the nature of the various minerals of igneous rocks are most common. Based on the calculation of 1.672 analysis of various kinds of rocks, Clarke concluded that 99.22% of rocks composed of 11 oxides (see table right). Other constituents occur only in small amounts. [Note 3]

Layers of the earth

According to the composition (type of material), the Earth can be divided into the following layers:

    * Earth's crust
    * Flat Earth

Earth's mantle lies between the crust and the outer core of the earth. Earth's mantle is a rock that contains magnesium and silicon. The temperature at the upper mantle ± 1300 ° C-1500 ° C and the temperature of the mantle in ± 1500 ° C-3000 ° C

    * The core is

Meanwhile, according to the mechanical properties (properties of the material) it, the earth can be divided into the following layers:

    * Lithosphere
    * Astenosfir
    * Mesosphere
    * Earth's outer core

Earth's outer core is one part of the earth that coats the inner core of the earth. Earth's outer core has a thickness between 2250 km and a depth of 2900-4980 km. Earth's outer core composed of liquid iron and nickel with a temperature of 3900 ° C

    * Earth's inner core

Earth's inner core is the deepest part of the earth or the earth's core can also be called. Earth's core has a diameter of 2600km and 1200km thick. core is composed of iron and nickel solid with temperature can reach 4800 ° C