What is in the center of the earth? The inner structure of the planet. The deep structure of the globe

In the summer of 1971, a young geologist named Mike Vurhis led to the survey in the overgrown area of \u200b\u200bthe terrain in the east of Nebraska not far from his native town Orchard. Passing down the bottom of a deep ravine, he noticed something whitish at the top in the shrub and rose to look. There he saw a perfectly preserved skull of a young rhino, washed away by the recently strong rains.

And a few meters from it, as it turned out, was the most unusual burial of the fossil residues, ever open in North America: dried with reservoirs, which served as a common grate of many dozens of animals - rhino, zebrid horses, saber-toothed deer, camels, turtles. All died as a result of a mysterious cataclysm a little less than 12 million years ago, in a period known in geology as Miocene. In those days, Nebraska was located on an extensive hot plain, very similar to Serengeti in the present Africa. Animals were found buried under volcanic ashes of three-meter thickness. The mystery was that there were never any volcanoes in Nebraska.

Today, Vurhis open is called the Eshfolla fleet of the burial of fossil animals. There is a new center for visitors and a museum with well-thought-out exposures on the geology of the Nebraski and the history of the burial of fossil animals. The center includes a laboratory with a glass wall, through which visitors can see paleontologists engaged in cleaning skeletons.

At first, it was believed that the animals were buried by alive, and Vurhis in 1981 in the article in National Geographic just as wrote. "In the article, the place of finds are called" Pompeiyi prehistoric animals, "he said - it was unsuccessful, because soon scientists realized that the animals were not died immediately. They all suffered from a certain ailment called hypertrophic pulmonary osteodistrophy, which occurs when inhaling a large amount of solid abrasive particles, and they must have inhaled a lot, because hundreds of miles around the layer of ash reached thickness a few feet. " Apparently, they came here on the waterway, looking for relief, and instead in the torment gibbles. Ashes, apparently, destroyed everything. I buried the whole grass, covered every sheet and turned the water into a snag for drinking to drink.

In the documentary program "Horizon" it was said that the presence of such a number of ashes in Nebraska was a surprise. In fact, about the huge seals of the ashes in Nebraska for a long time. For almost a hundred years it was mined for the manufacture of household cleaning powders of the "comet type" or "Ajax". But, oddly enough, it did not occur to anyone to ask where all the ashes came from.

Vurhis sent samples to colleagues in all Western states with a request to report, do they have something like something. A few months later, a geologist from the geological service of Idaho Bill Bonnichsen was contacted with him and said that ash corresponds to volcanic sediments in the town of Bruno Jarbridge in the south-west of Idaho. The phenomenon that killed animals on the plains of Nebraski was the eruption of the volcanic of unprecedented scale - such that was covered with a three-meter layer of ash territory at a distance of 1600 km from him, in the west of Nebraska. It turned out that under the western part of the United States was a giant magmatic boiler, a colossal volcanic focus, catastrophically sped up to approximately every six hundred thousand years. The last such eruption was a little more than six hundred thousand years ago. The focus remains in place. Today we call him Yellowstone National Park.

We are strikingly little know what is happening under our feet. It is terrible to think that Ford began to produce cars, and the Nobel Committee began to award award for a long time before we learned that the Earth had a kernel. Yes, and the idea that the continents float on the surface, like leaves of the water lily, has become generally recognized less than generation back. "Oddly enough, Richard Feynman wrote," we understand the distribution of the substance inside the Sun, much better than in the inner structure of the Earth. "

The distance from the surface to the center of the Earth is 6370 km, which is not so much. It is estimated that if you dig a well to the center and throw a brick into it, then it will take it to the bottom in just 45 minutes (although it will be weightless at that point, since all the severity of the earth will not be at the bottom, but at the top and around). Attempts to move in the direction of the center were truly modest. In South Africa, one or two gold mine reaches the depth of more than 3 km, and the depth of most of the mines and mines on Earth does not exceed 400 m. If the planet was an apple, we would not even pour the skin. In fact, we would not even approach it.

A little less than a hundred years ago, the most aware of the minds knew about the depths of the Earth not much more than miner - namely, that for some distance you deepen into the ground, and then rest in the hard rock, and that's all. Then in 1906, the Irish geologist R. D. Oldham, studying the earthquake seismograms in Guatemala, noticed that individual shock waves penetrated to a certain point deep into the ground, and then they reflected at an angle, as if they met some obstacle. Hence he concluded that the Earth has a kernel. Three years later, the Croatian seismologist Andrei Mochorovichich studied the earthquake diagrams in Zagreb and noted such an unusual deviation, but at a lesser depth. He opened the border between the bark and the layer directly under it, the mantle. Since then, this zone is known as the surface of Mochorovichich, or, for brevity, mohaw.

So we started to get a vague idea of \u200b\u200bthe layered inner structure of the Earth - the truth is really very vague. Only in 1936, the Dane of Inge Lemann, studying the seismograms of earthquakes in New Zealand, found that there are two cores: the inner, which we now consider solid, and the external (the fact that I discovered Oldham), which is considered liquid and, as believable is The focus of magnetism.

Just around at a time when Lehmann, studying seismic waves during earthquakes, clarified our initial ideas about the internal structure of the Earth, two geologists from Caltex in California developed a way to compare one earthquake with another. These were Charles Richter and Beno Gutenberg, although for reasons that do not have any attitude to justice, the scale almost immediately became known for the name of one Richter. (Richter also had nothing here. Being a modest person, he never called the scale with his name and always referred to her as a "magnitude scale".)

Of course, the scale is rather a concept than a thing, an arbitrary measure of the oscillations of the Earth, based on the measurements made on the surface. It increases exponentially, so the earthquake of magnitude is 7.3 V 32 times more powerful than the earthquake of magnitude 6.3, and 1000 times more powerful than 5.3.

At the very least, theoretically, the earthquakes do not have the upper boundary, and if so, then the bottom. The scale simply serves as a measure of force, but nothing speaks of destruction. The earthquake of magnitude 7 deep into the mantle - let's say, at a depth of 650 km, - may not cause any destruction on the surface, then as much weaker, but at a depth of 6-7 km, can cause huge destruction. Much also depends on the nature of the occurrence of rocks, the duration of earthquakes, the frequency and seriousness of the impetus, following the main impetus, and from the physical condition of an earthquake-affected area. Of all this it follows that the most terrible do not necessarily have the strongest earthquakes, although the power undoubtedly means a lot.

Earthquake - phenomena is quite ordinary. Daily somewhere in the world there is a pair of earthquakes by force 2 points and more - sufficient so that the nearby are decent shakes. The most common types of earthquakes are those that arise in the meeting places of two tectonic plates, as in California along the fled San Andreas. As the plates are written on each other, the pressure is growing until one or another will be given. Generally speaking, the longer the interval between earthquakes, the stronger the contained pressure and the greater the likelihood that the shake will be really strong.

Since we cannot look inside the Earth, to find out what is located there, you have to resort to other ways, mostly to study the properties of waves passing through the subsoil. Something you can learn about the mantle on formations, called kimberlite tubes, in which diamonds are formed. The following happens: deep in the bowels of the earth there is an explosion, which throws onto the surface, essentially the charge of magma. The phenomenon is absolutely unpredictable. The kimberlite tube can break out in your yard when you are busy ordinary affairs.

Since they are pulled away from such a great depth - up to 200 km, - kimberlite tubes put such substances on the surface that you usually do not find on the surface or near it: a breed, called peridotite, olivine crystals and is only occasionally, in one tube from a hundred, - Diamonds. A lot of carbon comes out with kimberlite emissions, but most of it evaporates or turns into graphite. Only from time to time the required mass is thrown into combination with the desired speed and the cooling time, which leads to the formation of diamonds. It is these tubes that Iohhannesburg turned into the richest world diamond center.

However, there may be other, even larger tubes that we do not know about. It is known to geologists that somewhere next door to the northeastern part of Indiana there are evidence of the existence of a tube or group of tubes, which can be truly colossal. In the area scattered around the area, diamonds of up to 20 carats were found and even more. But no one discovered their source. As John McChe notes, he can be buried under the glacial sediments, like the Manson Crater in Iowa, or is under great lakes.

So, what do we know about the bowels of the earth? Very little. In general, scientists agree that the world under us consists of four layers - solid external cortex, a mantle of a hot mating rock, a liquid external core and a solid indoor core.

It is known that silicates are dominated on the surface; They are relatively lungs and they are not enough to provide the observed average density of the Earth as a whole. Consequently, inside there should be a more severe matter. It is known that to form our magnetic field somewhere inside there should be a dense belt of metal elements in a liquid state. This is what is generally accepted. But almost all above - how the layers interact, which determines their behavior as they will behave in the future - it seems at least indefinite, and more often extremely uncertain.

Even we see the part of the globe - the bark, and that is the subject of quite loud disputes. Almost all works on geology states that the Earth Cora reaches from 5 to 10 km under the oceans, about 40 km under the mainland and 65-95 km under large mountain chains, but within the framework of these generalized data there are many puzzling deviations. The bark under the mountains of Sierra Nevada, for example, has a thickness of only 30-40 km, and no one knows why. According to all the laws of Geophysics, Sierra Nevada should be descended, as if to go to the eyelid sand. (Some believe that maybe it is.)

As and when the Earth found his bark - a question that shares geologists into two large camps: on those who believe that this happened suddenly at the beginning of the history of the Earth, and those who believe that this happened gradually and somewhat later. The theory of early sudden emergence in the early 1960s, Richard Armstrong was put forward from the University of Yale, who had dedicated the rest of his scientific activities to combat those who did not agree with him. He died of cancer in 1991, but shortly before the death "broke out to his critics on the pages of the Australian geological journal, accusing them to perpetuating fictions," Earth magazine ("Earth") wrote about him in 1998. "He died embittered," he told one of his colleagues.

The bark and part of the outer mantle together are called a lithosphere (from the Greek "Lithos", meaning "stone"), which, in turn, floats on a layer of a softer rock, called an asthenosphere (from the Greek words meaning "devoid of force"). But such terms never fully meet the meaning. For example, it is to say that a lithosphere floats on the surface of the asthenosphere, means to mean a certain degree of buoyancy, which is not entirely correct. Similarly, incorrectly represent rock rocks by fluid, like liquids on the surface. Mountain breeds are fluid, but only in the sense, in what fluid glass. This, maybe not visible by the eye, but all the glass on Earth under the unusual influence of gravity flows down the book. Remove the very old glass from the frame in the window of the European Cathedral, and it will be noticeably thicker below, the above. Here we are talking about such "fluidity". The hour arrow moves ten thousand times faster than the "fluid" rocks of the mantle.

Movements occur not only horizontally, as the earth plates are moved over the surface, but also up and down, how the rocks are rising and lowered in the vortex process known as convection. Convection as the process first introduced into circulation eccentric graph von Rumford at the end of the eighteenth century. Sixty years later, English Parish priest Osmond Fisher suggested that the contents of the earth's subsoil may well be fluent in order to move. But a lot of time passed before his idea gained support.

In about 1970, geophysics experienced a fair shock, realizing that there, inside, turbulent, indiscriminate processes occur. As writes in his book "Nagaya Earth: New Geophysics" Shavna Fogel: "It was like that as if scientists dozens of years studied the earthly atmosphere - the troposphere, the stratosphere, and so on, and then suddenly learned about the wind."

Since then, the disputes around the depth reaches the convection process. Some say that it begins at a depth of 650 km, others are deeper than 3 thousand km. The problem, as James Trefil noted, is that "there are two groups of data from two different disciplines that cannot be reconciled." Geochemists say that some elements cannot fall on the surface of the planet from the upper mantle, and should be climbing from deeper revenge grounds. Therefore, the substances of the upper and lower mantle must, at least, periodically mix. Seismologists say that this thesis does not find confirmations.

So, it is only possible to argue that, moving to the center of the Earth, in some not quite a certain moment we leave the asthenosphere and plunge into the clean mantle. If we take into account that the mantle is 82% of the volume of land and 65% of its mass, it does not receive unnecessary attention, mainly because the interest of scientists, and indeed readers lies either much deeper (as in the case of magnetism) or closer to the surface (earthquake). It is known that before the depth of about 150 km as part of the mantle prevailing the form of a rock, known as peridotitis, but what the remaining 2650 km is filled, it is not exactly known.According to the message in the magazine Nature, it does not seem to be peridotit. Nothing more we know.

Below the mantle is two nuclei - solid interior and liquid external. Do not have to say that our ideas about the nature of these nuclei are indirect, but scientists are able to make some reasonable assumptions. They know that the pressure in the center of the earth is very high - about three more than a million times more than on the surface, it is enough to make any breed solid. From the history of the Earth (as well as on indirect signs) it is known that the inner core holds very well. Although it is only a little more than an assumption, it is believed that in four more than a billion years, the temperature of the core fell no more than 110 degrees Celsius. Nobody knows exactly how hot is the core of the Earth, but the estimates range from 4,000 to more than 7,000 degrees Celsius - it is almost as hotly as on the surface of the sun.

The external core in many ways has been studied even less, although everyone converges that it is liquid and that there is a source of magnetism. In 1949, E. S. Bullard from Cambridge University put forward the theory according to which this liquid part of the globe rotates in such a way that, in essence, turns it into an electric motor that creates the magnetic field of the Earth. It is assumed that convection flows of fluid inside the Earth create an effect like current in the wires. What exactly is happening - it is unknown, but rather definitely believed that this is due to the rotation of the nucleus and with the fact that it is liquid. Bodies that do not have a liquid core, such as the moon and Mars, do not possess magnetism.

It is known that the tension of the magnetic field of Earth from time to time changes: in the era of dinosaurs it was 3 times higher than now. It is also known that on average approximately every 500 thousand years, it changes polarity, although the monstrous degree of unpredictability is hidden behind this average. The last change took place about 750 thousand years ago. Sometimes polarity remains unchanged millions of years - it seems that the longest gap was 37 million years, and at another time the polarity changed in just 20 thousand years. In just the last 100 million years, it changed about 200 times, and we actually have no idea why. This fact is called "the greatest stay without answering a question in geophysical science."

Perhaps, just today we are experiencing a polarity shift. The magnetic field only has less than six percent over the last century. Any weakening of magnetism is likely to be bad news, because magnetism other than attaching notes to refrigerators and the reliable work of the compasses plays a crucial role in maintaining our lives. In the universe, full of dangerous cosmic rays, which, do not be magnetic protection, would pierce our bodies, turning the majority of our DNA into unsuitable flasks. When the magnetic field acts, these rays are securely distilled off from the surface of the Earth and are collected in the herd in two zones of the near-earth space called Van Allen's belts. They also interact with particles in the upper layers of the atmosphere, creating charming light curtains, known as polar radiances.

Our ignorance is largely due to the fact that scientists traditionally took care of the consistency of studies of what is happening on the surface of the Earth and in its depths.

The land is part of the solar system along with the rest of the planets and the sun. It refers to the class of stone solid planets, characterized by a large density and consisting of rocks, in contrast to gas giants with large sizes and relatively low density. At the same time, the composition of the planet causes the internal structure of the globe.

The main parameters of the planet

Before you know which layers are highlighted in the structure of the globe, let's talk about the basic parameters of our planet. The land is at a distance from the Sun, approximately 150 million km. The nearest celestial body is the natural satellite of the planet - the moon, which is located at a distance of 384 thousand km. The earth-moon system is considered unique, as it is the only one where the planet has so large satellite.

Ground mass is 5.98 x 10 27 kg, approximate volume - 1.083 x 10 27 cubic meters. See Planet drawn around the Sun, as well as around its own axis, and has a slope relative to the plane, which causes the change of seasons. The period of treatment around the axis is approximately 24 hours, around the Sun - just over 365 days.

Mysteries of the inner structure

Before the method of studying the subsoil with seismic waves was invented, scientists could only make assumptions about how the land was arranged inside. Over time, they developed a number of geophysical methods, which made it possible to learn about some features of the structure of the planet. In particular, the widespread use of seismic waves, which are recorded as a result of earthquakes and movements of the earth's crust. In some cases, such waves are generated by artificially in order to familiarize themselves in the nature of their reflections with the situation at depth.

It is worth noting that this method allows you to get data indirectly, since it is not possible to directly get into the depths of the subsoil. As a result, it was found that the planet consists of several layers, characterized by temperature, composition and pressure. So what is the internal structure of the globe?

Earth's crust

The upper solid shell of the planet is called its thickness varies from 5 to 90 km, depending on the type of type, there are 4. The average density of this layer is 2.7 g / cm cu. The largest capacity has a mainland bark, the thickness of which comes to 90 km under some mountain systems. Also distinguished under the ocean, the thickness of which comes up to 10 km, transitional and riftogenic. Transitional is characterized by the fact that it is on the border of the mainland and oceanic cortex. The rift bark is found where there are mid-ocean ridges, and is characterized by a small thickness that reaches only 2 km.

The bark of any type consists of rocks of 3 types - sedimentary, granite and basalt, which differ in density, chemical composition and nature of origin.

The lower border of the crust is called in honor of its opener by the surname Mochorovichich. It separates the bark from the underlying layer and is characterized by a sharp change of phase state of the substance.

Mantle

This layer follows solid crust and is the largest - its volume is approximately 83% of the total volume of the planet. The mantle begins immediately after the border of Mokho and extends to the depths of 2900 km. This layer is additionally subdivided into the upper, middle and lower mantle. A feature of the upper layer is the presence of asthenosphere - a special layer, where the substance is in a state of low hardness. The presence of this viscous layer explains the movement of continents. In addition, in the eruption of volcanoes, the liquid molten substance extended by them comes from this area. The upper mantle ends at a depth of about 900 km, where the average starts.

Distinctive features of this layer can be called high temperatures and pressure that increases with depth increments. This determines the special state of the substance of the mantle. Despite the fact that in the depths of the rock have a high temperature, they are in solid state due to exposure to large pressure.

Processes occurring in the mantle

The decrace of the planet has a very high temperature, due to the fact that the process of thermonuclear reaction continuously occurs in the kernel. However, a comfortable condition is preserved on the surface. This is possible due to the presence of a mantle that has thermal insulating properties. Thus, the heat released by the kernel enters it. The heated substance rises upwards gradually cooling, while the mantle is divered from the upper layers of the manta. This cycle is called convection, it happens without stop.

The structure of the globe: kernel (external)

The central part of the planet is a kernel that begins at a depth of about 2,900 km, immediately after the mantle. At the same time, it is clearly divided into 2 layers - external and internal. The thickness of the outer layer is 2,200 km.

The characteristic signs of the outer layer of the nucleus are the predominance of iron and nickel, in contrast to the compounds of iron and silicon, of which the mantle is mainly. The substance in the external core is in a liquid aggregate state. The rotation of the planet causes the movement of the liquid substance of the nucleus, which is why a powerful magnetic field is formed. Therefore, the external core of the planet can be called the planet magnetic field generator, which deflects hazardous types of ospace radiation, due to which life is able to bore.

Inner kernel

Inside the liquid metal shell is a solid inner core, the diameter of which reaches 2.5 thousand km. Currently, it is still not previously studied, and relative to the processes occurring in it, there are disputes between scientists. This is due to the difficulty of obtaining data and the possibility of using only indirect research methods.

It is known that the temperature of the substance in the inner core is at least 6 thousand degrees, however, despite this, it is in a solid state. This is due to very high pressure, which does not give the substance to move into a liquid state - in the inner core, it is presumably equal to 3 million atm. In such conditions, there may be a special state of substance - metallization, when even such elements such as gases can acquire properties of metals and become solid and dense.

As for the chemical composition, there are still disputes in the research environment about which elements are internal core. Some scientists suggest that the main components are iron and nickel, others - that among the components can also be sulfur, silicon, oxygen.

The ratio of elements in different layers

The earth's composition is characterized by a large variety - it contains almost all elements of the periodic system, but their content in different layers is inhomogeneously. So, the smallest density, so it consists of the easiest elements. The most heavy elements are in the core in the center of the planet, at high temperature and pressure, providing the process of nuclear decay. This ratio was formed for a certain time - immediately after the formation of the planet, its composition was supposedly more uniform.

In the lessons of geography, students can offer to draw the structure of the globe. To cope with this task, you need to adhere to a specific layer location sequence (it is described in the article). If the sequence is broken, or one of the layers is missed - then the work will be performed incorrectly. Also, you can also see the sequence of layers in the photo presented to your attention in the article.

Planet Earth stores a huge amount of secrets, a special place among which is riddled about its inner structure. The deepest mines who managed to create a person are achieved in the length of just a few kilometers. Despite the fact that it is impossible to penetrate the inside of our planet, scientists managed to draw up an approximate picture of its inner structure.

What happens inside our planet?

All that is in the center of the Earth should be in the molten and liquid state. However, this is not true, because for each 1 cm 3 mantle from the surface of the earth's crust is the pressure of 13 tons. Approximately such a kamaz weight loaded asphalt. Scientists suggest that for this reason, the mantle and the core can be in a solid state.

If our planet could be cut into two half, then layers that are in the center of the Earth, would be visible to us as a few circular layers. The first one is the earthly bark. Its thickness is approximately 20 to 50 km. The type of terrestrial crust, called continental, consists of granite. In some places, for example, such as a large canyon, the water washed down the top layer of the earth's crust, and the granite layer became accessible to study and observation. At the bottom of the oceans, the earth's bark is also located, but its thickness is significantly less - just about 4.5 km. It consists not from granite, but from basalt.

Mantle - layer next to the crust of the earth

If you move to the center of our planet, the crust will follow the earthly crust. Researchers call this layer "the most powerful". The thickness of the mantle reaches 3000 km. If the tunnel could be cut through the mantle, then in order to drive from one end to another by car at a speed of 80 km / hour, it would take 36 hours. However, in fact, such a journey is impossible. After all, the land mantle is a place where huge temperatures and tremendous pressure are dominant. Presumably, it consists of lead, magnesium and iron, and the temperature of this layer reaches 2 thousand about S. No one really saw the mantle - after all, even this gigantic temperature, according to researchers, increases by 1 ° C with the promotion of deep into Every 30 meters. Mantle gets a large amount of heat and from the kernel, which has even a higher temperature.

Scientists throughout the history of the development of geology asked about what is in the center of the Earth. However, still knowledge about this part of our planet cannot be called exhaustive. It is reliably known that the upper layers of the mantle consist of a rock breed that is called peridotitis. In turn, peridotitis consists of a variety of minerals - olivine, pyroxen, as well as a grenades that are known to all jewelers used for the manufacture of jewelry.

Center Planet

Finally, the core is located in the very center of the Earth. It is located directly under the mantle. Its diameter is approximately 6400 km. At first glance, isolated from the heat and sun of the Earth's core should have a very low temperature. However, this area is just a place of unthinkable heat. Here, the temperature ranges from 2200 to 3300 o C. Earth's core is a liquid, molten metal with an admixture of sulfur and oxygen. This part of our planet has a huge density, because it is most scented with the entire mass of the upper layers.

Why are metals that are in the center of the earth, have such a high temperature? It is believed that the heat is stored in the core of our planet already 4.6 billion years old, since it was formed. However, most of the heat, according to geologists, is the result of radioactive decay processes within the Earth.

How is the structure of the earth?

How did scientists manage to detect everything that is in the center of the Earth, make an idea of \u200b\u200bits internal structure? After all, in reality, no device can get to the center of our planet. First of all, the conclusions about the inner structure of our planet became possible due to the study of volcanic eruptions. From the depths of the Earth during the eruptions, hot gas is broken, molten metals. Thus, scientists were able to understand what was in the center of the Earth. The mystery of the structure of our planet was also solved with the study of seismic activity.

Study of seismic activity

At a depth of about 3 thousand km. Seismic waves move differently on the surface of the planet. Some can dramatically change the direction of their movement, others - suddenly disappear. Powered by various education in their hardness, seismic waves change their character. With the help of sensitive equipment, scientists managed to recreate the intended internal structure of our planet. Such studies have become possible only thanks to scientific progress, technology development. Once upon a time, humanity was inclined to believe that the land is located in the center of the Universe, and is also flat. However, these naive assumptions were denied long ago. Today, humanity has all the possibilities of further study of our mysterious planet, including its internal structure.

From time immemorial, people tried to depict Schemes of the internal structure of the Earth. They were interested in the land of the Earth as a storage room of water, fire, air, as well as as a source of fabulous wealth. From here - the desire to penetrate the thought in the depths of the Earth, where, according to Lomonosov,

hands and OKU drugs nature (i.e. nature).

The first scheme of the internal structure of the Earth

The greatest thinker of ancientness Greek philosopher, who lived in the IV century BC (384-322), taught that there is a "central fire" inside the land, which breaks out from the "Furgent Mountains". He believed that the waters of the oceans, leaking into the depths of the earth, fill the emptiness, then in the cracks, the water rises again, forms the keys and rivers that fall into the sea and oceans. So the cycle of water is performed.

The first scheme of the building of the land of Afanasia Kirhera (according to Engraving 1664)

Since then, more than two thousand years have passed, and only in the second half of the XVII century - in 1664 appeared the first scheme of the internal structure of the Earth. Her author was Athanasius Kirger. She was far from perfect, but quite piety, as it is easy to conclude, looking at the drawing.

The Earth was depicted by a solid body, within which huge voids were combined with each other and the surface with numerous channels. The central kernel was filled with fire, and emptiness, which is closer to the surface, - and fire, and water, and air.

The scheme compiler was convinced that inside the ground the fire foci warmed it and produced metals. Material for underground fire, according to its ideas, served not only sulfur and stone coal, but also other mineral substances from the ground. Underground water flows spawned winds.

The second scheme of the internal structure of the Earth

In the first half of the XVIII century appeared the second scheme of the internal structure of the Earth. Her author was Woodworth.. Inside the Earth was not filled with fire, but water; Water created an extensive water sphere, and the channels connected this sphere with seas and oceans. A powerful solid shell consisting of rocks of rocks surrounded the liquid core.

Mountain breeds

About how they are formed and located mountain breeds, first pointed out the outstanding researcher of the Nature of the Dane Nikolay Stensen (1638-1687). A scientist lived in Florence under the name of the wall, engaged in medical practice there.

The miners have long noticed the logical location of sedimentary rocks. Szensen not only correctly explained the reason for their education, but also further changes they were subjected.

These layers, according to his conclusion, downtreated from the water. Initially, the sediments were soft, then harded; At first, the layers climbed horizontally, then, under the influence of volcanic processes, have experienced significant movements than and the slope is explained.

But what was right in relation to sedimentary rocks can not, of course, distribute to all other breeds, the gorges of the earth. How did they form? Is the aqueous solutions or from fire melts? This question is for a long time, up to the 20s of the XIX century, caught the attention of scientists.

Dispute between neptune and plutonists

Between the supporters of water - neptune (Neptune - the ancient Roman god of the seas) and fire supporters - plutonists (Pluto - the ancient Greek God of the underground kingdom) has repeatedly arose hot spores.

Finally, the researchers have proven the volcanic origin of basalt breeds, and the Neptunes were forced to recognize themselves defeated.

Basalt

Basalt - Extremely common volcanic breed. It often goes to the surface of the earth, and at high depths forms a reliable foundation. earth crust. For this breed - heavy, dense and solid, dark color - characterized by a columnal addition in the form of five-six-coal separates.

Basalt is an excellent building material. It, besides, be smelted and is used to produce basalt casting. Products have valuable technical qualities: refractory and acid-absorption.

From basalt casting, high-voltage insulators are made, chemical tanks, sewage pipes, etc. Basalts are found in Armenia, in Altai, in Transbaikalia other areas.

Basalt differs from the rest of the breeds with a large proportion.

Of course, it is much more difficult to determine the density of the Earth. And it is necessary to know in order to correctly understand the structure of the globe. The first and at the same time fairly accurate determination of the density of the Earth were made two hundred years ago.

The density was taken on average of many definitions equal to 5.51 g / cm 3.

Seismology

Significant clarity in the idea of \u200b\u200bintroduced science seismology, studying the nature of earthquakes (from ancient Greek words: "Seismos" - earthquake and "Logos" - science).

In this direction there is still a lot of work. According to the figurative of the largest seismologist, Academician B. B. Golitsyn (1861 -1916),

any earthquakes can be likened to lambay, which is lit for a short time and, covering us the inside of the earth, it makes it possible to consider what is happening there.

With the help of very sensitive self-sash seismograph devices (from the already familiar words "seismos" and "grapho" - I write) it turned out that the speed of distribution of earthquake waves through the globe is not the same: it depends on the density of substances through which the waves are distributed.

Through the thickness of sandstone, for example, they take two more times more slowly than through granite. This made it possible to make important conclusions about the structure of the Earth.

Earth, by modern Scientific views can be represented in the form of three bowls invested in each other. There is such a children's toy: a color wooden ball consisting of two halves. If it is revealed, inside the other color ball turns out, in it - the ball is even less and so on.

• First Outdoor Ball in Our Example - earth's crust.
• Second - earth shell, or mantle.
• The third - inner kernel.

The wall thickness of these "balls" is different: the outer is the thinnest. It should be noted here that the earth's crust is not a homogeneous layer of the same thickness. In particular, under the territory of Eurasia, it varies within 25-86 kilometers.

As determined by seismic stations, i.e. stations studying earthquakes, the thickness of the earth's crust along the Line of Vladivostok - Irkutsk- 23.6 km; between Peter and Sverdlovsky- 31.3 km; Tbilisi and Baku - 42.5 km; Yerevan and Terrible - 50.2 km; Samarkand and Chimkent - 86.5 km.

The thickness of the Earth's shell, on the contrary, is very impressive - about 2900 km (depending on the thickness of the earth's crust). The core shell is somewhat thinner - 2,200 km. The most internal kernel has a radius of 1200 km. Recall that the Equatorial radius of the Earth is 6378.2 km, and Polar - 6356.9 km.

Earth's substance at large depths

What happens to substance of landconstituting the globe at large depths?
It is well known that the temperature increases with depth. In the coal mines of England and in the silver mines, Mexico is so high that it is impossible to work, despite all sorts of technical devices: at a depth of one kilometer - over 30 ° heat!

The number of meters to be descended into the depths of the earth so that the temperature rose by 1 ° is called geothermal Step. Translated into Russian - "The degree of heating of the Earth". (The word "geothermal" is composed of two Greek words: "GE" - Earth, and "Terme" - heat. What is similar to the word "thermometer".)

The magnitude of the geothermal stage is expressed in meters and happens different (in the range between 20-46). On average, it takes 33 meters. For Moscow, according to data, deep drilling, the geothermal gradient is 39.3 meters.

The deepest drilling well is not exceeding 12000 meters. At a depth of over 2,200 meters, overheated steam appears in some wells. It is successfully used in industry.

However, in order to make the right conclusions from here, it is necessary to take into account the exposure to the pressure, which is also continuously increased as the earth approaches the center.
At a depth of 1 kilometer, the pressure under the mainland reaches 270 atmospheres (under the bottom of the ocean at the same depth - 100 atmospheres), at a depth of 5 km - 1350 atmospheres, 50 km - 13,500 atmospheres, etc. In the central parts of our planet, the pressure exceeds 3 million atmospheres!

Naturally, the melting point will change with the depth. If, let's say, basalt melts in factory ovens at 1155 °, then at a depth of 100 kilometers it will start melting only at 1400 °.

According to the assumptions of scientists, the temperature at a depth of 100 kilometers is equal to 1500 ° and then slowly increasingly, only in the most central parts of the planet reaches 2000-3000 °.
As laboratory experiments show, under the influence of recessful pressure, solids - not only limestone or marble, but also granite - acquire plasticity and detect all signs of fluidity.

This state of the substance is typical for the second ball of our scheme - the shell of the Earth. The foci of molten mass (magma), directly related to volcanoes, have limited sizes.

Core of land

Shell substance nuclei of the Earth viscous, and in the very core, due to huge pressure and high temperature, it is in a special physical condition. Its new properties are similar to hardness with the properties of liquid bodies, and in relation to electrical conductivity - with the properties of metals.

In the large depths of the Earth, the substance passes, as scientists say, in the metal phase, which is not possible while creating in the laboratory conditions.

Chemical composition of the elements of the globe

Brilliant Russian Chemist D. I. Mendeleev (1834-1907) proved that the chemical elements represent a slim system. Their qualities are among themselves in natural relationships and represent the consecutive steps of a single matter from which the globe is built.

• In the chemical composition, the earth's boron is mainly formed only nine elements Of the more than one hundred we known. Among them, first of all oxygen, silicon and aluminumthen, in smaller quantity, iron, calcium, sodium, magnesium, potassium and hydrogen. The rest accounts for only two percent of the total weight of all listed elements. The earth's boron, depending on its chemical composition, was called SIAL. This word indicated that silicon predominates in the earth's crust after oxygen (in Latin - Silicium, hence the first syllable - "SI") and aluminum (the second syllable - "al", together - "SIAL").
• In a subcortical shell, magnesium increases noticeably. Therefore, it is called sim.. The first syllable - "C" from the Silitia - silicon, and the second - "Ma" from magnesium.
• The central part of the globe believed mainly formed from nickelist glazeFrom here her name - nife. The first syllable - "ne" indicates the presence of nickel, and "fee" - iron (in Latin "Ferrum").

The density of the earth's crust is average equal to 2.6 g / cm 3. With depth there is a gradual increase in density. In the central parts of the nucleus, it exceeds 12g / cm 3, and sharp jumps are noted, especially on the border of the core shell and in the inner core itself.

Large works 0 of the structure of the Earth, its composition and processes of the distribution of chemical elements in nature left us outstanding Soviet scientists - Academician V. I. Vernadsky (1863-1945) and his student Academician A. E. Fersman (1883-1945) -tlaland popularizer, The author of fascinating books is "entertaining mineralogy" and "entertaining geochemistry."

Chemical analysis of meteorites

The correctness of our ideas about the composition of the internal parts of the Earth is also confirmed chemical meteorites analysis. In some meteorites, iron dominates - they are called iron meteorites, in others - those elements that are found in the rocks of the earth's crust, why they are called stone meteorites.

Stone meteorites are fragments of external shells of broken celestial bodies, and iron - fragments of their inner parts. Although on external signs, stone meteorites are not similar to our rocks, but the chemical composition is close to basalts. Chemical analysis of iron meteorites confirms our assumptions about the nature of the central nucleus of the Earth.

Atmosphere of land

Our ideas about the structure Earth will be far from complete if we are limited only to its subsoils: the earth is surrounded primarily by the air sheath - atmosphere (from the Greek Words: "Atmos" - Air and "Sfira" - ball).

This atmosphere, which was surrounded by a newborn planet, contained water in a vapor state of the future oceans of the Earth. The pressure of this primary atmosphere was therefore higher than modern.

As the atmosphere is cooling, the overheated water flows were poured on the ground, the pressure became lower. Hot water created the primary ocean - the water shell of the Earth, otherwise the hydrosphere (from the Greek "Hydore" - water), (more details :). Water shell covering most of the surface of the globe (about 71%) forms a single world ocean.

The study of the depths of the ocean showed that its outlines change. Those data we have currently about marine depths cannot be attributed to the primary ocean, since the most ancient deposits are in most shallow water. Consequently, small reservoirs prevailed in the oldest epochs of the development of our planet, now we are observing the return ratio.

(Lesson "The structure of the globe", grade 6)

Geography lesson in the 6th grade "Building of the globe"

The purpose of the lesson:formation of ideas about the inner structure of the globe: the kernel, mantle, earthly crust, the lithosphere, on the ways to study the earthly subsoil.

Tasks:

Educational: Familiarize children with inner layers: earth bark, mantle, core; establish similarities and differences in the mainland and oceanic earthly crust; Give concepts: Lithosphere; Give an idea of \u200b\u200blearning the earth's crust.

Developing: To form skills to apply the knowledge gained in solving practical tasks, allocate the main one from the seen and heard, fill the tables, clusters schemes.

Educational:

Educating students from working in small groups (pairs), skills to listen to the answers of classmates, analyze and evaluate them. Formation of students of independent, responsible thinking. Education of a positive attitude to the answers of classmates.

Forms of organization of training activities: Frontal, individual, steam room.

Teaching methods: Vitely - illustrative, explanatory illustrative, partly - search, practical work.

Receptions: Analysis, synthesis, conclusion, generalization, visual form of material organization.

Equipment: Screen, laptop, presentation, cards with table "Internal structure of the Earth"

Type of lesson:lesson studying new material

During the classes

I. Organizational moment. Reflection (1 min.)

Hello guys. Today, we came to visit us to see how the lesson passes, as you do. Let's say hello to them.

II. Message of a new topic. Setting goals (5 min.).

So, we are moving to the study of 3 sections called ...

And this we learn by completing the test "Geographical Card". Recall the material of the past section.

Perform a task in the route sheet, fill the table by choosing letters with the correct answers. Slide 2.

Mutual responses. Estimation.

With the right choice of answers, you will have the topic of the next section. HYDROSPHERE

1. The location plan specified the named scale of "1 cm - 6 m". What numerical scale does it match?

A) 1: 6 V) 1: 6000

B) 1:60 D) 1: 600

2. Conditional line on the geographic map, separating land on the North and South Hemisphere, is called:

C) northern tropical k) zero meridian

B) southern tropical And) Equator

3. The length of the circumference of the Earth by Equator:

A) 4400 km and) 400000 km

E) 40,000 km D) 40040 km

4. Geographical longitude is:

M) North and South O) South and Eastern

B) northern and western P) western and eastern

5. From the equator counts:

C) Western and Eastern Longitude

T) North and South Longitude

C) Western and Eastern Latitude

O) North and South Latina

6. The high-quality background method can be depicted on the map:

C) the depth of the ocean E) river

C) cities and) mineral deposits

7. Azimuth directions north-east is:

Y) 0 ° F) 45 °

P) 90 ° D) 295 °

8. Exceeding one point of the earth's surface above the other is called:

A) relief M) absolute height

L) isoypsoy E) relative height

9. Area - these are lines of equal:

A) depth g) temperatures

P) heights Y) speeds

10. The curiosity is located on the map of the oval, the slope:

N) above k) longer

A) cooler Y) smaller

0-1 Errors - "5"

2-3 errors - "4"

4-5 errors - "3" Slide 3.

And what is the globe?

Today we will find out and understand this, which building has our land inside .. So, what is the subject of the lesson today? (offer options for themes of the lesson).

The subject of the lesson is "the structure of the globe." Slide 4.

Record the lesson and date in the notebook.

Based on the topic, specify the purpose of the lesson.

After reviewing the text in the textbook, scroll it into parts.

So, we will study this topic according to the following plan:

1) the internal structure of the Earth;

2) study of the subsoil of the earth;

3) Litosphere.

III. Study of a new material (22 min)

1) the structure of the globe

Now we read on the roles of the story "Candy Earth" (distribution of roles) Slide 5.

Vasya: Kohl, Kolya! - I ran into the room Vasya, - I came to me such an idea!

Kolya: What, Vasya?

Vasya: Earth is like a ball, yes? - Vasya clarified.

Kolya: Well yes...

Vasya: So if we dig up the land, we will be in another place, right?

Kolya: For sure! - Poland was delighted, "we will go more like a grandmother, ask where we have a shovel.

Vasya: Ran!

Kolya: Baaaaaabushka!

Grandmother: What, knee?

Kolya: Grandmother, where do we have a shovel?

Grandmother: In Saraj, Kolya. Why do you need a shovel? - answered grandma.

Kolya: We want to break through the land, perhaps somewhere and fall, - Kolya said happily.

Grandma smiled and asked:

Grandmother: Do you at least know how it works?

Vasya: And what is there to know, - Vasya answered, - Earth Earth - what could be easier!

Grandmother: But no. Not everything is so simple - the grandmother answered.

Kolya: But as? Grandma, tell me, please. Well, poaaaaluista! - He began to settle his grandmother Kolya.

Grandmother: Well, okay, okay - the grandmother agreed, and began his story.

Grandmother: The land is like a candy: in the center of nuts - the kernel, then the creamy filling goes - it is a mantle, and on top of a chocolate glaze - this is the earthly bark. The distance only from here to the center of the nucleus is more than 6,000 km, and you want to try, - my grandmother grinned.

Kolya: So, everything is canceled, "Kolya was upset ...

Vasya: Daaa, it would be nice such candy, "Vasya said dreamily.

- Summing up the story

Working with a picture "What can I compare the Earth" slide 6.

You can compare the planet with an egg, peach, cherry, watermelon? What is the similarity?

Shell, skin - earth bark; Protein, flesh - mantle; Sadryshko, protein - core. The earth has a layered structure.

Working with a textbook. Filling the table. Steam work (writing). Slide 7.

Using the textbook material (p.57 §9), fill in the "Internal Structure of the Earth" table (cells). Steam work (mutual test). Estimates in the estimated list.

The inner structure of the Earth

Slide 8.

Self-standard. Installing the mark in the estimated list

Fizminutka

Words disclined by class:+ 6000 ° C, kernel, + 3 ° C, mantle, earth bark, 5-10 km., Mainland

1) What is the temperature of the nucleus?

2) How many degrees increase the temperature of the earth's crust for every 100 m?

3) Earth shell consisting mainly of iron.

4) The capacity of this layer of the Earth is 2900 km.

5) top layer of land?.

6) What earth bark consists of 3 layers?

7) What is the power of the ocean terrestrial crust?

2) Study of the Earth's subsoil.

Slide 9.

Geological methods - based on the study of the outcrops of rocks, cuts of mines and mines, drilling fluids, make it possible to judge the structure of the near-surface part of the earth's crust. The deepest in the world of the well on the Kola Peninsula, has already reached a depth of more than 12 km at the design depth of up to 15 km. In volcanic areas on products of eruption of volcanoes, one can judge the composition of the substance at depths of 50-100 km.

In general, the deep inner structure of the Earth is being studied mainly by geophysical methods. One of the most important methods is seismic (Greek. "Seismos" is a shaking) Method based on the study of natural earthquakes and "artificial earthquakes" caused by explosions or shock vibrational effects on the Earth's Cour.

View video "Study of the Substitute of Earth" Slide video 10

3) Litosphere

Guys, what is a lithosphere? Find in the text on page 60 the definition of the word "lithosphere" and write down in the notebook.

Lithosphere: "Lithos" - stone, "sphere" - ball. This is a solid, the stone shell of the Earth, consisting of the earth's crust and the upper part of the mantle.

Record definition in a notebook

IV. Fastening (7 min).

1) "Find compliance"

Self-esteem: 0 Errors - "5", 1 Error - "4", 2 errors - "3"

2) Fill the pass

In the center of the Earth there is a kernel, the radius of which is approximately equal to 3.5 thousand km, and the temperatures correspond to 6000 ° C. The largest internal shell is mantle, the temperature of which is 2000 ° C. In its upper part, a solid layer is distinguished, which, together with the earth's crust, forms a solid shell of the Earth - a lithosphere. The earth's crust is divided into two main types: the mainland and oceanic. Under the continents, the earth Cort is thicker than under the oceans and has 3 layers.

Check, reading the answers alternately

Self-esteem: 0-1 error - "5", 2-3 errors - "4", 4-5 errors - "3"

2) Cluster slide 11.

Key phrase - the structure of the globe

Group work.

V. Final part (5 min)

1. Homework: & 9, make up an intelligence card Slide 12.

2. Reflection

Technological card lesson

Subject: Geography

Theme lesson: "The structure of the globe"

Type of lesson: lesson learning new knowledge

The purpose of the lesson: the formation of ideas about the inner structure of the globe: the core, mantle, earthly crust, the lithosphere, on the ways to study the earthly subsoil.

Lesson's technology: development of critical thinking, semantic reading technology

Here will be the file: /data/edu/files/y1451934151.docx (technological card lesson)