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Viewings: 4069Earth was formed out of that substance, which was thrown away from the Sun? So it makes sense to start the history of the Earth from the very beginning - from the moment of formation of the Sun. The sun in its current form was formed 6-7 billion years ago. The earth was formed about 4.6 billion years ago. Star - the Sun - from the very beginning was not as it is now. Each star is born, lives and dies. Our modern Sun is a stage in the development of the life of stars.
Each star is formed from gas clouds, which under its own gravity gradually shrinks. As the compression of the substance density increases. When it reaches a certain critical value, then starts crushing (fragmentation) of a single cloud. Each piece of broken clouds compressed - and it makes a star.
The main characteristic, which determines the splitting of the original cloud, is the density of matter in the cloud. If the radius of the cloud will decrease twice, the density will increase by 8 times. The initial cloud from which subsequently formed our Galaxy, consisted of hydrogen. When it broke up into separate parts, then when they gravitational compression began to turn into stars. The formation of stars was as follows.
Cloud-protostar shrank under the action of gravitational forces. At a certain stage of compression clouds its density increases so that it ceases to let out the infrared radiation of the substance of the cloud. This leads to very fast growth of temperature in the Central areas of the cloud. There is a large temperature difference between the Central part of protostars and external layers. Differential pressure causes convection processes that seek to equalize the temperature in the entire cloud - protostar. In the outer layers of the protostar the temperature reaches approximately 2500 C. Protostar continues to shrink its size decreases. The temperature in its interior continues to increase. At some point it reaches ten million degrees . Then "enabled" thermonuclear reactions involving hydrogen nuclei (proton - proton reaction), and protostar stops shrinking. This means that protostar has turned into a star.
Energy star, which is supported by high temperature in the depths, taken from fusion. In these thermonuclear reactions four protons by different transformations are connected so that they form a helium nucleus (an alpha particle consists of two protons and two neutrons) . At transformation of some particles in the other part of their mass is transformed into energy. So you can assess the reserves of nuclear energy star.
Further evolution of a star is determined mainly by its mass. The larger the mass of the star, the more energy that can be released inside of a star in thermonuclear reactions, the more fuel is contained within such stars. It would seem that such a star must live (turn on) longer. But it is not. Than the more massive the star, the more it radiates energy in outer space. If the mass of the stars to increase three times, the consumption of energy in radiation (luminosity) will be increased nine times. Therefore, with increasing the mass of the star duration of her life dramatically reduced. For example, the fuel for a nuclear reactor inside the Sun will suffice for tens of billions of years. About five billion years, the fuel is already spent. But if the mass of a star 50 times the mass of the Sun, its fuel will last only for a few million years!
When in the process of thermonuclear reactions in the core of the star is used up all the hydrogen (he turns into helium), the nuclear fusion reactions converting hydrogen to helium begin to walk in the layer around the nucleus. The luminosity of the star on the stage increases. The star swells as if. But the temperature of the surface layers of the star decreases as the size of its increased. So she starts to Shine not blue, and red. Such a star called a red giant. On the star evolves as follows. Since the kernel does not go thermonuclear reactions and not the heat, it gradually shrinks under the action of gravitational forces. As a result of compression of the nucleus increases its temperature. She reaches 100-150 million degrees. At such high temperatures helium becomes a source of heat: go thermonuclear reaction, in which the nuclei of helium into the carbon nuclei. The pressure inside the cores of stars increased, so the compression stops. The luminosity of a star at this stage is increasing because of the energy release from the kernel. The result is longer and surface temperature of a star.
But when something ends and helium. Moreover, much faster than had run out of hydrogen. When this happens, the star loses its outer layers. They are expanding and are separated from the core of the star. These layers subsequently observed as a planetary nebula. After this point, the events will develop in one of three options (scenarios). What option is implemented, it depends only on the mass of the star. If the mass stars less than 1.2 of the present mass of the Sun, the matter of the star under the action of gravitational compression compacted in such a way that its density reaches 10 thousand tons per cubic centimeter. With such huge density of atoms collapse. Then compress the stars stopped, as he begins to counteract the force of elasticity formed very dense gas. Such a star (it is called "dead") is a white dwarf. Recall that before the star becomes a white dwarf, it for a while becomes a red giant. Then a white dwarf in a few billion years cools down and in the end turns into a black dwarf, that is in the body, which already does not radiate. Star dies and stops to radiate. Experts often called "corpse". In the Universe there is an infinite number of cemeteries stars turned into black dwarfs. This is the fate of our Sun, which was once a red giant. But it lost the substance of it formed the planets of our system, including the Earth. What happens with the stars, the weight of which more than 1.2 the mass of the Sun, we described in detail in the book etc" (AKIS, 1993). Here only say that those of stars, the weight of which more than 1.2, but less than 10 Solar masses, in the end turn into a neutron star. This is a very unique objects. The density of a substance such star is equal to the density of matter inside the atomic nucleus! To receive such a substance on Earth impossible. If the mass of the star exceeds 10 Solar masses, then it turns into a black hole, the radius of which are equal to only 1-3 km So greatly reducing (and compacted) the substance is so massive and initially huge star.
But back to the Sun. The predecessor of the Sun, red giant, discarded his substance, which consisted largely of heavy chemical elements. The reset occurs in the form of the explosion. After the red giant sheds its coat, he turns into a supernova. Scientists word star" down and just say "supernova". Thus, our Sun after the red giant stage turned into a supernova. But in the solar space it lost the stuff from which formed the planets of the Solar system. It happened so.
After a few hundred million years of the solar cloud cleared the Sun substances gradually began to cool. It began to appear solid dust particles. All particles cloud was moving around the Sun, and gradually began to move in the Equatorial plane of the Sun, forming a kind of disk. It was a jet of solid particles and gases that occupies space in the form of the disk and moving around the Sun. According to the laws of motion was sort of particles according to their size and density: the closer to the Sun, the greater the density of the acquired material. Therefore the terrestrial planets that are closer to the Sun than the rest, was formed from the more dense substances. Therefore, they are smaller. This is mercury, Venus, Earth and Mars. More distant planets were formed from the volatile elements and lighter gas, so they and larger. This is Jupiter, Saturn, Uranus, Neptune and Pluto.
About 5 billion years ago "has drawn" the germ of the Earth. But the process of its formation lasted for about one billion years. Only after that the Land was gradually cool down and turned into a cold lifeless accumulation of cosmic matter. But after hundreds of millions of years it cooled matter again began to warm up, but for other reasons. The energy for this came from impact of cosmic bodies, and also due to radioactive decay of chemical elements. Melt if this earthly substance completely or only partially, hard to say. One thing is clear liquid (or partially liquid) the substance of the Earth had the opportunity under the force of gravity to be transferred to the density of a substance, on its specific weight. This is the most dense substance consisting of heavy elements and compounds, headed towards the center of the Earth. In the inner part of the Earth is dominated by iron (35%) ; followed by oxygen (30%) , followed by silicon (15%) and magnesium (12%) . The substance of the Earth contains a significant amount of radioactive substances during decomposition of which is heat. This heat is enough to raise the temperature in the middle of the Earth up to 6000 C. Under the forces of gravity and heat formed and the structure of the Earth: in the core of it is the nucleus, which is surrounded by a mantle. Outside the robe covers the earth's crust.
The core of the Earth withconsists of two parts : internal and external. The outer boundary of the earth's core is at a depth of 2900 km Below this boundary (i.e. core) density of a substance increases jump-8 0%. The outer core is liquid. The inner part of the core consists of an iron-Nickel alloy and behaves like a solid body. The pressure in the downtown core, and thus in the center of the Earth, which is about 3 million atmospheres. The temperature there is about 10 000 C. In the interior of the nucleus concentrated only 1.7% of the whole mass of the Earth. More massive is the outer part of the kernel. It contains nearly one third of the entire Land mass. But the density of matter in the external part of the kernel is much less than in the interior, because it's diluted with light grey. Its there to 14%.
I believe that immediately after the formation of the Earth, its core was completely molten. Then it gradually began to cool, and today molten only its outer part. Interestingly, the outer boundary of the kernel is not an ideal sphere. This layer with a unique relief, the thickness of which in different places different from 150 to 350 km
The core of the Earth is surrounded by a mantle. It stretches from 30-50 up to 2 900 km in depth. Rock mantle contains 80% olivine (Mg, Fe)2[SiO4] and 20% of pyroxene (Mg, Fe)2[Si2O6]. This breed is called the peridotite. It is a greenish minerals, silicates of magnesium and iron.
In the mantle high temperature. So the deep rocks melt and turn into magma. This magma on cracks breaks up in the form of lava. Actually, the Earth is 82% of the mantle. She, of course, will vary. Scientists divide it into the top and bottom. But the most important element, a layer of the mantle is a layer in the upper mantle, where the rocks are in a partially molten. The melt is only 1-3%. But this is enough to provide very peculiar dynamics of the whole upper part of the Earth. Due to weak melt substances in this layer, he was named "asthenosphere" ("astinos"- weak). It laboratornoe substance is not liquid, and leak it may not. But it serves as a kind of "grease", which moved the hard lithospheric plates, which form the top of the solid shell of the Earth. This wrapper is called "lithosphere" (from the Greek "Litos"- stone) .
The crust is different thickness on the continents and under the oceans. It thicker just where rise the mighty mountain ranges. Oceanic crust is thinner continental. The composition also varies. Oceanic crust is composed of two layers - basalt and sedimentary. Basalt is dark green or even black silicate rock that contains calcium, sodium, magnesium, and iron (and sometimes aluminum). Oceanic crust is allocated from the topmost layer of the mantle, which is under the ocean floor at a depth of just 10 to 50 km. There, in the upper layer of the mantle, the breed is in a molten state and from there on cracks comes up, where and solidifies, forming a basalt layer of crust.
The crust on the continents formed differently. It consists of several layers. The top layer is composed of sandstones, clays and limestones; the next layer (which is not in oceanic crust) formed granites and metamorphic rocks that have changed under the influence of high temperature and pressure. This is the main layer of the earth's crust continents. In addition, the base layer in the earth's crust are sedimentary rocks - sandstones, clay, basalt. Basalts and similar breeds make up the lower part of the continental crust. Continental crust formed long ago, more than 3 billion years. Oceanic crust appeared in geological terms just, just 150-170 million years.
All the physical Earth is in constant motion. So, any part of the lithosphere is constantly moving on the horizon. Of course, we do not notice it, because the movement is only a few tens of centimeters a year. But for geological periods of time this movement reaches thousands of kilometers. Look at a map or globe and mentally or on the drawing slide America to Africa. They are very good mix. It has done in the middle of the XIX century Antonio Snider. It combined the Atlantic ocean and received a vast continent. At this point it gave not only the similarity of the coastlines of Africa and America. In the hands of scientists found and other data, which testified about the complete similarity of fossil plants Carboniferous period of the Paleozoic era, which were found in Europe and North America. Hence, fossil trees that grew into a big forest, half of which were in distant America, and the other half remained in Europe. Scientist rushed to share his discovery with all and in 1858 he published the book, "the Universe and its secrets exposed". But in this stunning (and well-substantiated) news nobody believed him, and all was forgotten. And only in 1910-1912 Alfred Wegener again raised this question. So there was an idea floating ("drifting") continents, which has since been known as "the hypothesis of Wegener". Another injustice! Wegener was named a United continent, which then fell apart, "common Ground" ("Pangea") . But why and how the continents drift, Wegener and his contemporaries not figured out. Only by the end of 60-ies of our century, gradually began to unravel. The essence of the case was as follows.
I used to think that solid crust floating on the molten substance. The facts of this view seems to confirm. Judge for yourself. When in the last century has measured the force of gravity in the Himalayas, it is established that under the great weight of the Himalayas crust subsided. However, she was plunged into a layer of thick, viscous substance. Weight pushed deep substances, as required by the law of Archimedes, is equal to the mass of mountains.
Another example. During glaciation in the Quaternary period in Scandinavia crust buckled under the weight of ice. Over time, the ice melted away, and freed from the burden of the earth's crust began to regain its former position. She started to rise up -- rapidly at first, then slower. This process continues in our time - the earth's crust in Scandinavia continues to surface at a rate of one centimeter per year.
The facts described reliable, but their interpretation is wrong. Below the crust is not liquid, and solid. And so for thousands of kilometers deep down to the core of the Earth. So why and how floats crust? It's no flies, but only offset by a layer of grease - the asthenosphere. But the asthenosphere is not directly under the earth's crust. Above it is and part of the mantle. This part of the mantle and crust, that is all that is over the asthenosphere, called the lithosphere. Thus, floats crust does not by itself, but together with the upper part of the mantle. In other words, floats (slides on a layer of grease) lithosphere. The thickness of the lithosphere beneath continents 150-300 km, and under the ocean from a few kilometers to 90 km. Thus, the lithosphere (including the earth crust floating on the asthenosphere. She rises, falls and slides horizontally relative to the lower mantle and the core of the Earth. If all the lithosphere was a single rigid sphere, then slide it could, especially rising or falling. But the lithosphere is not a unified whole. It is split into separate pieces, pieces called plates. Now the Earth lithosphere is composed of seven major plates and several smaller plates.
Lithospheric plates glide in different directions, down with each other. Resting in each other, they create tensions that end earthquakes. If boards are not against each other, and the costs, the voltage does not occur. It is clear that in the inner parts of lithospheric plates everything is stable, there is no earthquakes. All earthquakes are located along major schisms, that is along the border between the plates, and where are created tension and in the end there is an offset of one plate relative to another (Fig. 1). In that case, if the plates are spreading apart, during earthquakes on the surface appear deep crevices, which is called the rift (English riff - crack, a crack). Such boundaries receding from each other lithospheric plates are along the underwater mid-oceanic ridges. They are called divergent or divergent (from lat. divergere - discover the difference) . However, where there is convergence, and the collision of plates, along the border between the plates formed the high mountains, deep gutters and island arcs. The latter are mostly located around of Pacific ocean. Such boundaries between plates called converging or convergent (from lat. convergere - closer to converge).
Lithospheric plates can not only converge or diverge, but also to slide against each other along the fault line. This offset plates movement is transferred from one active zone to another. What if this earthquake is accompanied by the shift of rocks parallel to the fracture.
Lithospheric plates differ and composition of the rocks, of which they are composed. Their thickness is also different. Under the ocean lithosphere is much narrower than under the continents and under the shelves of the (extensive shallow water). There are plates entire ocean - thin. There combo, consisting of continental and oceanic parts. Thick lithospheric plates less mobile, which is natural. The oceanic plate the most mobile convection, matter moves up and others down. Where it is moving up and forms the upward flow, and the lithosphere is experiencing pressure from below. She rises and moves apart. There is a split of the lithosphere under the ocean she was thin) with simultaneous rise along the line of division. It formed the mid-oceanic ridges with cleft - rifts. In these places the cracks poured out of basaltic lava. Magma who filled in Tretsthe community eventually freezes. Thus, there is a crystal rock. It is shown in Fig. 2. Thus, on the one hand, the two parts of the mid-Atlantic ridge from the sides speeds ranging from a few millimeters to 18 cm per year. On the other hand, the resulting gap (which is constantly growing) is filled with a substance that comes out of the depths. So in this place schism forms new oceanic crust. In the ocean floor as if stretched expanding. Experts this process is called an English word spreading (deployment, spreading).
But the lithosphere can not only grow. This would be possible if it increased the size of Earth. And "if in one place to arrive, then in another place will decrease of"? In other words, there should be places where the lithosphere is reduced. This can happen in different ways. Part of the lithosphere can be absorbed (wallow in liquid mantle substance), be reduced by a collapse in the folds or hang one section to another. Easy to figure out what is happening in those places where the movement of mantle material at the junction of two convection cells directed downwards. In these places the oceanic lithosphere is pushed under the counter plate. It then flows mantle material is delayed to a depth where at high pressures substance plate significantly consolidated. Becoming heavier, this piece of lithosphere himself drowning in a viscous asthenosphere. He descends to the surface of the lower mantle. In this way the lithosphere may take a very deep. For example, under the Kamchatka she fell to a depth of more than 1000 km, where it and was lost. It is clear that in such places on the bottom of the ocean are formed deep trench, the depth of which can reach 10 km. So, the deepest this trench - Marianske in the Pacific ocean - reaches a depth of 11 km. In this trench has direct access to liquid mantle substance. So near the gutter is usually a chain of active volcanoes are lined up. An example of this are the volcanoes of the Kurile island arc and Kamchatka. They are located near the Kuril-Kamchatka trench. Volcanoes are formed above the place where the lithosphere, which is inclined goes to the depth starts melting at high pressure and temperature. Dive lithosphere occurs at a rate from 1 to 12 cm in GDM.
Thus, such a picture emerges. Lithospheric plates diverge along the mid-oceanic ridges and are moving to the deep-sea trenches, where they go out into the deep, and there are absorbed. But on the plates are continents. They are forced to drift along with the plates. If you are facing two continents, it is a conglomeration of these mountains like the Alps, the Himalayas, the Pamirs.
Thus, the oceanic lithosphere is born in the areas of divergence. Continental lithosphere increased thickness in the zones of collision. In those and other areas is most terrestrial and submarine volcanoes. In these places up hot solutions that bring metals. So here are formed ore deposits.
Very important circulation of substances in the described processes. It is that the oceanic crust plunges and returned into the mantle, she carries out there with a marine sediments that have accumulated on the bottom. They contain and rocks of organic origin. So in the mantle of the Earth are not only the elements of air and water, but also animals and plants have an impact on its members to depths of hundreds and even thousands of kilometers. The situation of those and other areas is not immutable. But always moving, circulates, convective substance of the Earth. In the crevices on the bottom of the ocean poured out not only the basalt lava. There are many hot spring mineral water. The water is rich in copper, zinc, manganese. The water temperature reaches 330 C. This so-called hydrotherms. Combinations of chemical elements from the solution of sources form at the bottom of growths, columns and pipes. Their height reaches 27 PM the pipes continues to rise hot solution. The pipe is like Smoking, because at the exit from the solution stand out small particles of minerals. Therefore, these pipes called black smokers (Fig. 3) . Around them are formed sediments rich in metals. There are formed and ferromanganese balls - concretions. Around them boils underwater life. There are not only bacteria and worms, but shellfish and even crabs. Interestingly, over time, in the above-described processes of the earth's crust thickens. This is because when formed crust begins to move away from a fault line, then under it freezes and the contents of magmatic center. So in the bottom part of the oceanic crust is formed mountain crystalline rocks. As a result the thickness of the crust can reach 7 km. On the bottom of the crust bottom grow the most refractory minerals asthenosphere, who remained after the selection of basalt mass. Therefore, the ancient oceanic crust, the more severe (iron-rich) rocks of the mantle have time to grow it from below. In those places where the ocean floor were formed in the Jurassic period, bottom thickness reaches 70-80 km 10 times greater than the thickness of the crust.
Since stick heavy rock, then over time the average density of the lithosphere is growing. This means that by becoming heavier, lithosphere more and more immersed in a viscous asthenosphere. Once the bottom of the ocean is omitted, then the depth of the ocean is increasing. The depth of the ocean, you can calculate the time of the formation of its bottom. It is clear that the further from the mid-ocean ridge, the bottom of the ancient. But basaltic crust is growing and top. It forms marine sediments. Their thickness in the most ancient parts of the ocean may reach 1km. The margins of continents it many times.
Thus, over time, the oceanic lithosphere becomes thicker and heavier. Such heavy plate in a collision with another plate (easier) is pushed under it and disappears in the depths. It is therefore not surprising that the ancient ocean floor, the less preserved. Here also there is a law of aging and death. Since the entire lithosphere (and oceanic as well) is in constant motion, then after a while the oceanic lithosphere will reach the shores of the ocean. This time is not more than 180 million years. It can be easily calculated if you know the speed and distance. So oceanic lithosphere of the age of more than 180 million years (Jurassic period), all died, drowned in the asthenosphere. Was left only individual pieces, wedges, which was included in the folded mountain belt at the edges of the continents. Thus, all the ocean floor very young. His age 18 0 million years or less. In comparison with the age of the Earth (4.6 billion years) is very small. So the basic information about geological processes is stored mainly in the continental crust.
Let us consider what happens when faced lithospheric plates. In that case, when converge oceanic and continental plates, the heavier the oceanic plate certainly goes under a continental. If there are two oceanic plates, it goes down more severe, and that means more ancient. Oceanic lithosphere is beginning to sink in deep-sea trench. At the beginning of this dive lithospheric plate goes down gently. But as the diving breed compacted under high pressure. Becoming heavier, stove starts sinking fast in the asthenosphere. However, she bent and goes down at a steep angle (almost vertical). When it gets in the denser mantle, her headlong rush slowed and it gradually passes in a mode of horizontal movement.
Care in the depths of the asthenosphere lithospheric plates accompanied by a series of earthquakes. First centers of earthquakes appear in the ocean under the slope of the trench. In this place the plate is bent before it goes into the mantle. On the outside of the bend stove stretched and cracked. But the largest number of earthquakes occurs where the oceanic lithosphere rests on another plate. This oceanic plate goes down under the counter plate. On the border of plates earthquakes. Towards paddlegame oceanic plates under the counter is split rocks. In those places where an oceanic plate goes to a depth of more than 100 km, earthquakes becomes less. While the earthquake foci are located inside descending plate. The reason is heated, and hence the expansion of rocks. Falling even lower in the region of high pressure, they are compressed. In these conditions, the minerals that make up the rock, moving to another state with a more solid structure, in which the atoms are Packed more tightly. Gradually drifting stove becomes unable to cause an earthquake because it is strongly warmed up and can no longer split. This happens at different depths, from a few tens of kilometers up to 700 km above process allows you to properly understand the order of earthquake occurrence.
Sloping areas, which penetrate deeply into the Earth's mantle, not only related to earthquakes. Above them near deep-sea troughs chain are active volcanoes. Such a chain of volcanoes stretching over thousands of kilometers around of Pacific ocean. They form "ring of fire". The origin of these volcanoes is. When oceanic plate descends and enters the high-pressure and high temperature, at a depth of 100-200 km from it stand out so-called fluids and a certain amount of molten material. These substances are directed upwards. At the bottom of the earth's crust as well as inside pockets are formed magma. This magma and break it down to the earth's surface in the form of volcanic lava. This is the physical nature of almost all of the volcanoes on the island arcs of the Earth. The same nature and volcanoes on the edge of the South American continent, as well as the chain of volcanoes of the Andes, whiche stretch for thousands of kilometers.
The emergence of the volcano is in a certain time - when the stove will be at a certain depth. The rule is : the more inclined area paddlegame one plate under another, the closer to the trough is a chain of volcanoes.
Can happen and collision of continents, when they come lithospheric plates. The specialists of this phenomenon is called a collision. This is a special case in which none of the boards do not stalkivaetsya inside, into the mantle. This prevents easy granite continental lithospheric plates. This leads to exfoliation of the rocks huge plates. This "stuff" piled near the surface in the form of mountain structures. Thus occurred the formation of the Himalayas and the Tibetan plateau. This happened during the collision of the Indian subcontinent with the southern edge of the Eurasian continent. This clash is still ongoing, although it began 45-50 million years ago. In this light rock top of the continental lithosphere smachivaetsya near the surface of the earth. While the rest of the hard lithosphere abruptly plunges into the asthenosphere. Great Caucasus mountains were formed in the result of collision of two continental lithospheric plates. About 10-11 million years ago, a single African-Arabian continent split along a huge crack - rift. From this moment Arabia began to move away from Africa, heading North. When this movement it still rotates counterclockwise. So powerful Arabian lithospheric plate squeezed more soft and pliable strata of rocks that have accumulated in the former Tethys ocean and its marginal seas. These compressed rocks and established a number of mountain ranges of different height and very complex internal structure. At compression of various breeds not only are compressed in folds, but crawl against each other. So are formed by tectonic covers.
At the Northern edge of the Grand Caucasian mountain belt (Ciscaucasia) are plain. They belong durable Scythian plate. To the South are elongated along latitude (from West to East) the mountains of the Great Caucasus. Their height is 5 km. Here are narrow depression Transcaucasia. There are mountain ranges of the Lesser Caucasus (Georgia, Armenia, Eastern Turkey and Western Iran) . To the South of them are plain Arabia. They belong to the Arabian lithospheric plate. Caucasian mountains formed in the grip of two solid plate - Arabian and Scythian. The highest mountains were formed where the Arabian plate solid wedge strongly squeezed yielding deposits. East and West of the mountains is much lower.
Educated in this way the mountain belt is under tremendous pressure. So he divided the long diagonal faults. This shifts, along which a separate part of the mountain belt slide over each other. These shifts and are caused by strong earthquakes. The last of these occurred in Armenia (1988) and in Turkey (1991) . Under the Caucasus mountains from the South pushed solid and durable Transcaucasian lithospheric plate. Therefore the southern slope of the Great Caucasus narrow and very steep, and the Northern - wide and gentle. On the southern slope deposits crumpled into a very complex folds. They overturned and pulled down and as if creeps on each other and on the array. In the result of paddlegame South Transcaucasian plate Great Caucasus mountains asymmetric. Their main ridge is located closer to the South.
The collision of continental lithospheric plates formed and the highest mountain in Europe - Alpes. Here "worked" two plates - Adriatic and the European Average. They not only faced, but has approached each other. Also formed and the Carpathians. The greatest mountain junction of the Pamir, Karakorum, Hindu Kush, Himalayas and the Tibetan plateau has arisen as a result of collision of Continental plates with Eurasia. This process began 10-15 million years ago and continues today. Indostan-Kai lithospheric plate and now moves northward, exerting enormous pressure on the rocks.
Cordillera of North America and the Andes mountains of South America was formed by the collision of oceanic and continental plates. We have said that in the beginning of the Mesozoic era all the continents was a single supercontinent - Pangaea. Over time, began the collapse of Pangaea on separate large lithospheric plates. Thus arose the Atlantic ocean. He widened in both directions from the long mid-ocean ridge. The same expansion area there and in the East Pacific ocean. From the material of the oceanic crust moves in both directions. The continents of North and South America with the adjacent areas of the bottom of the Atlantic ocean shifted to the West, towards the Pacific plate. The oceanic plate, as more severe, pushed under the continental. This led to the formation of mountains, which are not that other, as conglomeration of each other rocks. As a result, in the earth's crust formed folds, and on the Western edge of North and South America are growing mountains.
Curious origin chains long since abandoned volcanoes that reach thousands of kilometers. Each such chain (ridge) is built strictly logical: the further away from the starting point of the ridge, the younger of the volcano. The impression is that someone "burned" these volcanoes in strict sequence. As if he was moving along a ridge with a torch and lit volcanoes, one after the other. The scientists showed that it was so. Only this "one" moved from near the volcanoes, and under them - under the lithosphere in the mantle. This "one" was mantle stream. She moved from one place to the next, and so were created long ridge volcanoes. New volcano was ignited when the preceding already had time to go out. Specify only that moved not mantle jet under the lithosphere and the earth's crust and lithosphere was moving over the jet. Besides mantle jet worked not always quite intensively. And formed a long chain of dead volcanoes. We can only add that the place of the surface of the Earth mantle called jet hotspot". By the way, knowing the age of the long-extinct volcanoes and the distance between them, you can determine the speed of mantle jet, to be exact speed shift lithospheric plates in relation to the deep bowels of the Earth. Of course, the accuracy of such a definition speed is small, but other possibilities yet. And the speed of displacement of lithospheric plates defined by this method, very believable. So, on the ridge volcanoes of the Hawaiian ridge received the speed of movement of the crustal plate is equal to 10 cm per year. According to different chains of dead volcanoes experts see a mixture of the lithosphere-governmental plates for tens of millions of years. It is especially important to have information about the different movement of lithospheric plates at the same time. This method allows to get such information. Determine not only the speed but also its direction. For this, specialists came across moments in geological history of the Earth, when the direction of the displacement rate of lithospheric plates sharply changed. Such phenomena (turning points) occurred simultaneously for different plates. There was some global processes.
Analysis of speeds of displacement of lithospheric plates showed that the plates are more willing to move to the West. If we remember that the Earth rotates from West to East, it will become clear. In fact, there is a small overall turning to the West the whole lithosphere of the Earth relative to the lower mantle and core. Why is the gap of the lithosphere during the rotation of the Earth around its axis (lag relative to the deeper shell)? The fact that the force of attraction of the moon causes tidal waves in the atmosphere, hydrosphere and lithosphere. Of course, these waves in the lithosphere (earth's crust) is significantly weaker than in the oceans and in the atmosphere. Nevertheless, though they explicitly invisible, they affect the movement of lithospheric plates. When the tidal wave is formed in the lithosphere, the lithosphere resists bending. This generates force of a tidal braking. It is under the action of these forces during the rotation of the Earth around its own axis lithosphere few behind the rotation of the deeper layers of the Earth. The slowdown in the rotation of the earth's crust and the entire lithosphere seen in the drift areas of divergence (spreading) . Zone under-moving lithospheric plates (subduction zone) also drifting to the West, albeit with different speeds. Thus, those and other areas make complex movements: on their differences and under-moving superimposed Western drift. If the plate is being swallowed up by its end deep down into the mantle, and is inclined, it is good enough stabilizirovannami. It is located on the mantle anchor. On the motion of such plate less is the influence of Western drift, it "tries" scrolled along with the underlying mantle. An example of such sustainable zones are subduction zone (paddlegame) in the West of the Pacific ocean (under island arcs and troughs in the East Asia and Australia), which abruptly going down. Therefore, they are deeply "anchored" in the mantle.
The Western drift of the lithosphere can be observed firsthand. Or rather, not himself drift, and its consequences. One of these consequences is the asymmetry of the Pacific ocean. He on the one hand is surrounded by garlands of island arcs, and on the other by banks of the continents.
In the Western drift occurred and navigenie North America on the East Pacific rise. It had a strong influence on orogeny and volcanism in the Cordillera.
In conclusion we should say a few words about the consequences of the displacement of lithospheric plates. If the oceanic plate crawls under continental, it could mean the end of the continent. Under the Japanese island from the East, from the side of the Pacific ocean crawl up two oceanic lithospheric plate. Both of them are very close to the Islands. This led to the idea of the creators of the movie "the Death of Japan" to illustrate something that is inevitable when something will happen. Fortunately, PLthe ITA's move with a speed of 10 cm per year. So this will happen through many millions of years. But it will happen.
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