The structure of the globe. What is the internal structure of the Earth

Structure of the hand The shape of the hand mainly shows the strength of physical passions, but it can also be used to approximately judge a person’s soul, as well as the properties of his character. A very thin, narrow and delicate hand indicates a powerless, barren temperament and

20.2. The structure of desire In the desire created by the Creator, we distinguish five stages, which we conventionally designate as: This is the designation of the desire created by the Creator, the designation of creation. A desire consists of five parts, denoted by five letters. This is not the name of creation, but the name

(lesson "Structure of the globe", 6th grade)

Geography lesson in 6th grade “Structure of the globe”

The purpose of the lesson: the formation of ideas about the internal structure of the Earth: core, mantle, earth's crust, lithosphere, about methods of studying the earth's interior.

Tasks:

Educational: familiarize children with the internal layers: the earth's crust, mantle, core; establish similarities and differences in the continental and oceanic crust; give the concepts: lithosphere; give an idea of ​​the study of the earth's crust.

Educational: develop the ability to apply acquired knowledge when solving practical problems, highlight the most important things from what you see and hear, fill out tables and cluster diagrams.

Educational:

To develop in students the ability to work in small groups (pairs), the ability to listen to classmates’ answers, analyze and evaluate them. Formation of independent, responsible thinking in students. Cultivating a positive attitude towards classmates’ answers.

Forms of organization educational activities: frontal, individual, steam room.

Teaching methods: visually - illustrative, explanatory illustrative, partially exploratory, practical work.

Techniques: Analysis, synthesis, inference, generalization, visual forms of organizing material.

Equipment: screen, laptop, presentation, cards with the table “Internal structure of the Earth”

Lesson type: lesson on learning new material

During the classes

I. Organizing time. Reflection (1 min.)

Hello guys. Today guests came to us to see how our lesson is going and how you are studying. Let's say hello to them.

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

So, we are moving on to studying section 3 called...

And we will find out by performing the test " Geographic map" Let's remember the material from the previous section.

Complete the task on the route sheet, fill out the table, choosing the letters with the correct answers. Slide 2.

Cross-checking answers. Assessment.

At making the right choice answers you will get the topic of the next section. HYDROSPHERE

1. The named scale “1 cm - 6 m” is indicated on the site plan. What numerical scale does it correspond to?

A) 1:6 B) 1:6000

B) 1:60 D) 1:600

2. The conventional line on a geographical map dividing the Earth into the Northern and Southern Hemispheres is called:

B) the Northern Tropic C) the prime meridian

B) South Tropic I) the equator

3. Circumference of the Earth at the equator:

A) 4400 km I) 400000 km

D) 40000 km D) 40040 km

4. Geographical longitude is:

M) northern and southern O) southern and eastern

B) northern and western P) western and eastern

5. Measured from the equator:

C) western and eastern longitude

T) north and south longitude

B) western and eastern latitude

O) northern and southern latitude

6. Using the qualitative background method, you can depict on the map:

C) ocean depth D) rivers

B) cities I) mineral deposits

7. The azimuth of the direction to the northeast is:

U) 0° F) 45°

P) 90° D) 295°

8. The excess of one point on the earth’s surface over another is called:

A) relief M) absolute height

L) isohypsum E) relative height

9. Isohypses are lines of equals:

A) depths G) temperatures

P) heights U) speeds

10. The denser the isohypses are located on the map, the slope:

P) higher K) longer

A) cooler U) smoother

0-1 errors - “5”

2-3 errors - “4”

4-5 errors - “3” Slide 3

What is a globe?

Today we will find out this and figure out what structure our Earth has inside.. So, what is the topic of our lesson today? (offer options for lesson topics).

The topic of the lesson is “STRUCTURE OF THE EARTH.” Slide 4

Write down the topic of the lesson and the date in your notebook.

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

After looking through the text in the textbook, break it into parts.

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

1) Internal structure of the Earth;

2) Study of the Earth's interior;

3) Lithosphere.

III. Learning new material (22 min)

1) Structure of the globe

Now we will read the story “Candy Earth” by role (distribution of roles) Slide 5

Vasya: Kolya, Kolya! - Vasya ran into the room, - this idea came to my mind!

Kolya: Which one, Vasya?

Vasya: The earth is like a ball, right? - Vasya clarified.

Kolya: Well, yes...

Vasya: So, if we dig right through the Earth, we will end up in a different place, right?

Kolya: Exactly! - Kolya was delighted, - Let’s go to grandma quickly and ask where our shovel is.

Vasya: Let's run!

Kolya: Baaaaabushka!

Grandmother: What, Kolenka?

Kolya: Grandma, where is our shovel?

Grandmother: In the barn, Kolenka. Why do you need a shovel? - answered the grandmother.

Kolya: “We want to dig through the Earth, maybe we’ll get somewhere,” Kolya said joyfully.

Grandmother smiled and asked:

Grandmother: Do you even know how it works?

Vasya: “What do you know,” answered Vasya, “earth is earth - what could be simpler!”

Grandmother: No. “It’s not that simple,” answered the grandmother.

Kolya: But as? Grandma, please tell me. Well, please! - Kolya began to beg grandmother.

Grandmother: “Okay, okay,” the grandmother agreed and began her story.

Grandmother: The earth is like candy: in the center there is a nut - the core, then there is a creamy filling - this is the mantle, and on top there is chocolate icing - this is the earth's crust. The distance from here to the center of the core is more than 6,000 km, but you want to go straight through,” the grandmother grinned.

Kolya: So, everything is cancelled, - Kolya was upset...

Vasya: Yeah, it would be nice to have some candy like that,” Vasya said dreamily.

- Summing up the story

Working with the drawing “What can the Earth be compared to?” Slide 6.

Can the planet be compared to an egg, a peach, a cherry, or a watermelon? What are the similarities?

Shell, skin - earth's crust; protein, pulp - mantle; nucleolus, protein - nucleus. The earth has a layered structure.

Working with the textbook. Filling out the table. Pair work (written). Slide 7

Using the textbook material (p. 57 §9), fill in the blanks (cells) in the “Internal Structure of the Earth” table. Pair work (mutual check). Putting grades on the score sheet.

Internal structure of the Earth

Slide 8.

Self-assessment. Marking the score sheet

Fizminutka

Words posted around the classroom:+ 6000°C, core, +3°C, mantle, crust, 5-10 km, continental

1) What is the core temperature?

2) By how many degrees does the temperature of the earth’s crust increase for every 100 m?

3) The shell of the Earth, consisting mainly of iron.

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

5) The top layer of the Earth?.

6) Which earth's crust consists of 3 layers?

7) What is the thickness of the oceanic crust?

2) Study of the Earth's interior.

Slide 9

Geological methods - based on the study of rock outcrops, sections of mines and mines, boreholes, make it possible to judge the structure of the near-surface part of the earth's crust. The world's deepest well on the Kola Peninsula has already reached a depth of more than 12 km with a designed depth of up to 15 km. In volcanic areas, the products of volcanic eruptions can be used to judge the composition of matter at depths of 50-100 km.

In general, the deep internal structure The earth is studied mainly by geophysical methods. One of the most important methods is the seismic (Greek “seismos” - shaking) method, based on the study of natural earthquakes and “artificial earthquakes” caused by explosions or shock vibration effects on the earth’s crust.

Watch the video clip “Studying the Earth’s Interior” Slide video 10

3) Lithosphere

Guys, what is the lithosphere? Find the definition of the word “Lithosphere” in the text on page 60 and write it down in your notebook.

Lithosphere: “lithos” - stone, “sphere” - ball. This is the hard, rocky shell of the Earth, consisting of the earth's crust and the upper part of the mantle.

Writing the definition in a notebook

IV. Consolidation (7 min).

1) “Find matches”

Self-assessment: 0 errors - “5”, 1 error - “4”, 2 errors - “3”

2) Fill in the blanks

At the center of the Earth there is a core whose radius is approximately 3.5 thousand km, and temperatures correspond to 6000°C. The largest inner shell by volume is the mantle, whose temperature is 2000 °C. In its upper part there is a solid layer, which, together with the earth’s crust, forms the hard shell of the earth - the lithosphere. The earth's crust is divided into two main types: continental and oceanic. Under the continents, the earth's crust is thicker than under the oceans and has 3 layers.

We check by reading the answers one by one

Self-assessment: 0-1 error - “5”, 2-3 errors - “4”, 4-5 errors - “3”

2) Cluster Slide 11.

Key phrase - Structure of the globe

Group work.

V. Final part (5 min)

1. Homework : &9, make a mind map to it Slide 12.

2. Reflection

Technological lesson map

Subject: geography

Lesson topic: “Structure of the globe”

Lesson type: lesson on learning new knowledge

The purpose of the lesson: to develop ideas about the internal structure of the Earth: core, mantle, crust, lithosphere, and ways to study the interior of the earth.

Lesson technology: development critical thinking, semantic reading technology

The file will be here: /data/edu/files/y1451934151.docx ( routing lesson)

In the summer of 1971, a young geologist named Mike Voorhees was surveying a thistle-covered area in eastern Nebraska near his hometown of Orchard. Walking along the bottom of a deep ravine, he noticed something white in the bushes above and went up to take a look. There he saw the perfectly preserved skull of a young rhinoceros, washed by recent heavy rains.

And a few meters away, as it turned out, was the most unusual burial of fossil remains ever discovered in North America: a dried-up pond that served as a common grave for many dozens of animals - rhinoceroses, zebra horses, saber-toothed deer, camels, turtles. All died in a mysterious cataclysm just under 12 million years ago, during a period known in geology as the Miocene. In those days, Nebraska was located on a vast, hot plain much like the Serengeti in what is now Africa. The animals were found buried under three-meter-thick volcanic ash. The mystery was that Nebraska had never had any volcanoes.

Today, the site discovered by Voorhees is called the Ashfall Fossil Animal Burial Park. There is a new visitor center and museum with well-designed displays on Nebraska geology and the history of fossil burials. The center includes a laboratory with glass wall, through which visitors can see paleontologists busy cleaning skeletons.

At first it was believed that the animals were buried alive, and Voorhees wrote exactly so in an article in National Geographic in 1981. “In the article, the location of the finds is called “Pompeii of prehistoric animals,” he said. “The name was unfortunate, because scientists soon realized that the animals did not die immediately. They all suffered from something called hypertrophic pulmonary osteodystrophy, which occurs when inhalation large quantity solid abrasive particles, and they must have inhaled a lot, because for hundreds of miles around the layer of ash reached a thickness of several feet.” Apparently, they came here to drink, looking for relief, but instead died in agony. The ashes apparently destroyed everything. He buried all the grass under him, covered every leaf and turned the water into a brown sludge undrinkable.

The Horizon documentary said the presence of so much ash in Nebraska was a surprise. In fact, huge deposits of ash in Nebraska have been known for a long time. For almost a hundred years, it was mined to make household cleaning powders such as Comet or Ajax. But, oddly enough, it never occurred to anyone to ask where all this ashes came from.

Voorhees sent samples to colleagues in all Western states asking if they had anything similar. A few months later, Idaho Geological Survey geologist Bill Bonnichsen contacted him and said the ash was consistent with volcanic deposits near Bruno Jarbridge in southwest Idaho. The event that killed the animals on the Nebraska plains was a volcanic eruption of unprecedented proportions - one that covered an area 1,600 km away in western Nebraska with a three-meter layer of ash. It turned out that beneath the western United States there was a gigantic magma cauldron, a colossal volcanic chamber that catastrophically erupted approximately every six hundred thousand years. The last such eruption was a little over six hundred thousand years ago. The source remains in place. Today we call it Yellowstone National Park.

We know amazingly little about what is happening under our feet. It's scary to think that Ford began producing cars and the Nobel Committee began awarding prizes long before we knew that the Earth had a core. And the idea that continents float on the surface like lily pads became generally accepted less than a generation ago. “Strangely enough,” wrote Richard Feynman, “we understand the distribution of matter inside the Sun much better than we understand the internal 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, it will reach the bottom in just 45 minutes (although at this point it will be weightless, since the entire weight of the Earth will not be below, but above and around). Attempts to advance towards the center were truly modest. In South Africa, one or two gold mines reach depths of more than 3 km, and most of the mines and mines on Earth are no more than 400 m deep. If the planet were an apple, we wouldn't even pierce the skin. In fact, we wouldn't even come close to doing that.

A little less than a hundred years ago, the most knowledgeable scientific minds knew little more about the depths of the Earth than a miner - namely, that for some distance you go deep into the earth, and then you hit solid rock, and that's it. Then in 1906, Irish geologist R. D. Oldham, studying seismograms from an earthquake in Guatemala, noticed that individual shock waves penetrated to a certain point deep into the Earth, and then were reflected at an angle, as if they had encountered some kind of obstacle. From this he concluded that the Earth has a core. Three years later, Croatian seismologist Andrej Mohorovicic studied diagrams of the Zagreb earthquake and noted a similar unusual deviation, but at a shallower depth. He discovered the boundary between the crust and the layer immediately below it, the mantle. Since then, this zone has been known as the Mohorovicic surface, or Moho for short.

Thus we began to get a vague idea of ​​the layered internal structure of the Earth - admittedly, very vague indeed. It was only in 1936 that the Danish Inge Lehmann, studying seismograms of earthquakes in New Zealand, discovered that there were two cores: the inner one, which we now consider solid, and the outer one (the same one that Oldham discovered), which is considered liquid and is believed to be center of magnetism.

Just around the time Lehmann was refining our initial understanding of the Earth's interior by studying seismic waves from earthquakes, two geologists at Caltex in California were developing a way to compare one earthquake with another. These were Charles Richter and Beno Gutenberg, although for reasons that have nothing to do with justice, the scale almost immediately became known by the name of Richter alone. (Richter had nothing to do with this either. Being a modest man, he never called the scale by his name and always referred to it as the “magnitude scale.”)

Of course, a scale is more of a concept than a thing, an arbitrary measure of the Earth's vibrations based on measurements made at the surface. It increases exponentially, so that a magnitude 7.3 earthquake is 32 times more powerful than a magnitude 6.3 earthquake and 1,000 times more powerful than a magnitude 5.3.

At least theoretically, earthquakes have no upper limit, and if so, then no lower limit. The scale simply serves as a measure of strength, but does not say anything about destruction. A magnitude 7 earthquake deep in the mantle - say 650 km deep - might not cause any damage at the surface, while a much smaller one at a depth of 6–7 km could cause enormous damage. Much also depends on the nature of the rocks, the duration of earthquakes, the frequency and severity of tremors following the main shock, and the physical condition of the area affected by the earthquake. From all this it follows that the most terrible earthquakes are not necessarily the most powerful, although strength undoubtedly matters a lot.

Earthquakes are quite common phenomena. Every day, somewhere in the world, there are a couple of earthquakes of magnitude 2 or greater—enough to give those nearby a fair shake. The most common types of earthquakes are those that occur where two tectonic plates, like in California along the San Andreas Fault. As the plates push against each other, the pressure builds until one or the other gives way. Generally speaking, the longer the interval between earthquakes, the greater the pent-up pressure and the greater the likelihood that the shaking will be really strong.

Since we cannot look inside the Earth to find out what is there, we have to resort to other methods, mostly by studying the properties of waves passing through the bowels. You can tell something about the mantle from the formations called kimberlite pipes, where diamonds form. What happens is that an explosion occurs deep in the bowels of the Earth, which essentially throws a charge of magma onto the surface at supersonic speed. This phenomenon is completely unpredictable. A kimberlite pipe may burst out in your yard while you are doing normal activities.

Because they are dug up from such great depths - up to 200 km - kimberlite pipes bring to the surface substances that are not usually found at or near the surface: a rock called peridotite, olivine crystals and - only occasionally, in one pipe in 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 necessary mass is thrown out in combination with the required speed and cooling time, which leads to the formation of diamonds. It was these pipes that turned Johannesburg into the world's richest diamond center.

However, there may be other, even larger tubes that we do not know about. Geologists know that somewhere in the vicinity of northeastern Indiana there is evidence of a pipe or group of pipes that may be truly colossal. Diamonds up to 20 carats and even more were found in places scattered throughout the area. But no one discovered their source. As John McPhee notes, it may be buried under glacial deposits, like Iowa's Manson Crater, or beneath the Great Lakes.

So, what do we know about the interior of the Earth? Very little. In general, scientists agree that the world below us consists of four layers - a solid outer crust, a mantle of hot, sticky rock, a liquid outer core and a solid inner core.

It is known that silicates predominate on the surface; they are relatively light and not enough to provide the observed average density The earth as a whole. Therefore, there must be a heavier substance inside. It is known that for the education of our magnetic field somewhere inside there must be a dense belt of metal elements in liquid state. This is what is generally accepted. But almost everything beyond that - how the layers interact, what determines their behavior, how they will behave in the future - seems at least uncertain, and more often extremely uncertain.

Even the part of the globe that we see is the crust, and that is the subject of quite loud debate. Almost all works of geology say that the Earth's crust reaches 5 to 10 km beneath the oceans, about 40 km beneath the continents, and 65 to 95 km beneath the major mountain ranges, but within these generalizations there are many puzzling deviations. The crust beneath the Sierra Nevada mountains, for example, is only 30–40 km thick, and no one knows why. According to all the laws of geophysics, the Sierra Nevada should sink, as if sinking into quicksand. (Some people think this may be true.)

How and when the Earth acquired its crust is a question that divides geologists into two large camps: those who believe that it happened suddenly at the beginning of the Earth's history, and those who believe that it happened gradually and somewhat later. The theory of early sudden emergence was put forward in the early 1960s by Richard Armstrong of Yale University, who devoted the rest of his work to scientific activity fight against those who did not agree with him. He died of cancer in 1991, but shortly before his death, he “lashed out at his critics in the pages of an Australian geology journal, accusing them of perpetuating fiction,” Earth magazine wrote about him in 1998. “He died embittered,” said one of his colleagues.

The crust and part of the outer mantle are together called the lithosphere (from the Greek "lithos", meaning "stone"), which in turn floats on a layer of softer rock called the asthenosphere (from Greek words meaning "without strength"). But such terms never fully correspond to the meaning. For example, to say that the lithosphere floats on the surface of the asthenosphere means to imply a certain degree buoyancy, which is not entirely correct. Likewise, it is incorrect to imagine rocks as fluid, like liquids on the surface. Rocks are fluid, but only in the sense in which glass is fluid. This may not be visible to the eye, but all the glass on Earth flows downwards under the relentless influence of gravity. Take very old glass out of its frame in a European cathedral window and it will be noticeably thicker at the bottom than at the top. This is the kind of “fluidity” we are talking about. Hour hand moves ten thousand times faster than the “flowing” mantle rocks.

Movements occur not only horizontally, as the Earth's plates move across the surface, but also up and down, as rocks rise and fall in a swirling process known as convection. Convection as a process was first introduced by the eccentric Count von Rumford at the end of the eighteenth century. Sixty years later, the English parish priest Osmond Fisher suggested that the contents of the earth's interior may well be fluid enough to move. But it took a long time before his idea gained support.

Around 1970, geophysicists experienced a considerable shock when they realized that there were violent, chaotic processes taking place inside. As Shawna Vogel writes in her book The Naked Earth: The New Geophysics: “It was as if scientists had been studying the earth’s atmosphere for decades—the troposphere, the stratosphere, and so on—and then suddenly learned about wind.”

Since then, controversy has raged about how deep the convection process reaches. Some say that it begins at a depth of 650 km, others - deeper than 3 thousand km. The problem, as James Trefil noted, is that “there are two sets of data from two different disciplines that cannot be reconciled.” Geochemists say that some elements cannot reach the planet's surface from the upper mantle, but must rise from deeper within the Earth. Therefore, the substances of the upper and lower mantles must at least periodically mix. Seismologists say that this thesis is not confirmed.

So, we can only say that, moving towards the center of the Earth, at some not entirely certain moment we leave the asthenosphere and plunge into the pure mantle. Considering that the mantle makes up 82% of the Earth's volume and 65% of its mass, it does not receive too much attention, mainly because the interest of scientists and readers in general lies either much deeper (as in the case of magnetism) or closer to the surface (earthquakes). It is known that down to a depth of about 150 km, the mantle is dominated by a type of rock known as peridotite, but what fills the remaining 2,650 km is not known exactly.According to a report in the journal Nature, it does not appear to be peridotite. We don't know anything else.

Below the mantle there are two cores - a solid inner one and a liquid outer one. Needless to say, our understanding of the nature of these nuclei is indirect, but scientists are able to make some educated guesses. They know that the pressure in the center of the Earth is very high - about three million times more than on the surface - enough to make any rock solid. It is known from the history of the Earth (as well as from indirect evidence) that the inner core retains heat very well. Although this is little more than a guess, it is believed that in more than four billion years the temperature of the core has fallen by no more than 110 degrees Celsius. No one knows exactly how hot the Earth's core is, but estimates range from 4,000 to over 7,000 degrees Celsius - almost as hot as the surface of the Sun.

The outer core is in many ways even less studied, although everyone agrees that it is liquid and that the source of magnetism is located there. In 1949, E. S. Bullard of Cambridge University put forward the theory that this liquid part of the earth's core rotates in such a way that it essentially turns it into an electric motor that creates the earth's magnetic field. It is assumed that convection currents of liquid inside the Earth create an effect similar to current in wires. What exactly is happening is unknown, but it is fairly certain that it is related to the rotation of the core and 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 strength of the Earth's magnetic field changes from time to time: in the era of dinosaurs it was 3 times higher than now. It is also known that, on average, it changes polarity approximately every 500 thousand years, although this average hides a monstrous degree of unpredictability. The last change took place about 750 thousand years ago. Sometimes the polarity remains the same for millions of years - the longest period seems to have been 37 million years - and at other times the polarity changes after just 20 thousand years. It has changed about 200 times in just the last 100 million years, and we actually have no idea why. This fact has been called "the biggest unanswered question in geophysical science."

Perhaps we are experiencing a polarity change just these days. The magnetic field has weakened by about six percent over the last century alone. Any weakening of magnetism is likely bad news, because magnetism, in addition to attaching notes to refrigerators and making compasses work reliably, plays a vital role in keeping us alive. The Universe is full of dangerous cosmic rays, which, without magnetic protection, would pierce our bodies, turning most of our DNA into worthless scraps. When a magnetic field operates, these rays are reliably driven away from the Earth's surface and herd in two zones of near-Earth space called the Van Allen belts. They also interact with particles in upper layers atmosphere, creating enchanting curtains of light known as auroras.

Our lack of awareness is largely due to the fact that scientists have traditionally paid little attention to the consistency of studies of what happens on the surface of the Earth and in its interior.

Since time immemorial people have tried to portray diagrams of the internal structure of the Earth. They were interested in the bowels of the Earth as storehouses of water, fire, air, and also as a source of fabulous wealth. Hence the desire to penetrate with thought into the depths of the Earth, where, as Lomonosov put it,

hands and eyes are forbidden by nature (i.e. nature).

The first diagram of the internal structure of the Earth

The greatest thinker of antiquity, the Greek philosopher, who lived in the 4th century BC (384-322), taught that inside the Earth there is a “central fire” that bursts out from the “fire-breathing mountains.” He believed that the waters of the oceans, seeping into the depths of the Earth, fill the voids, then through the cracks the water rises again, forming springs and rivers that flow into the seas and oceans. This is how the water cycle occurs.

The first diagram of the structure of the Earth by Athanasius Kircher (based on an engraving from 1664)

More than two thousand years have passed since then, and only in the second half of the 17th century - in 1664 - appeared the first diagram of the internal structure of the Earth. Its author was Afanasy Kircher. She was far from perfect, but quite pious, as is easy to conclude by looking at the drawing.

The earth was depicted as a solid body, inside of which huge voids were connected to each other and the surface by numerous channels. The central core was filled with fire, and the voids closer to the surface were filled with fire, water, and air.

The creator of the diagram was convinced that fires inside the Earth warmed it and produced metals. The material for underground fire, according to his ideas, was not only sulfur and coal, but also other mineral substances of the earth's interior. Underground water flows generated winds.

Second diagram of the internal structure of the Earth

In the first half of the 18th century there appeared second diagram of the internal structure of the Earth. Its author was Woodworth. Inside, the Earth was no longer filled with fire, but with water; the water created a vast water sphere, and channels connected this sphere with the seas and oceans. A thick solid shell, consisting of rock layers, surrounded the liquid core.

Rock layers

About how they are formed and located rock layers, first indicated outstanding researcher nature Dane Nikolai Stensen(1638-1687). The scientist lived for a long time in Florence under the name Steno, practicing medicine there.

Miners have long noticed the regular arrangement of layers of sedimentary rocks. Stensen not only correctly explained the reason for their formation, but also the further changes to which they were subjected.

These layers, he concluded, settled from the water. Initially the sediments were soft, then they hardened; At first the layers lay horizontally, then, under the influence of volcanic processes, they experienced significant movements, which explains their tilt.

But what was right about sedimentary rocks, cannot, of course, be extended to all other rocks that make up the earth’s crust. How were they formed? Are they from aqueous solutions or from fiery melts? This question attracted the attention of scientists for a long time, right up to the 20s of the 19th century.

Dispute between Neptunists and Plutonists

Between supporters of water - Neptunists(Neptune - the ancient Roman god of the seas) and supporters of fire - plutonists(Pluto is the ancient Greek god of the underworld) heated debates arose repeatedly.

Finally, researchers proved the volcanic origin of basaltic rocks, and the Neptunists were forced to admit defeat.

Basalt

Basalt- a very common volcanic rock. It often comes to the surface of the earth, and at great depths it forms a reliable foundation earth's crust. This rock - heavy, dense and hard, dark in color - is characterized by a columnar structure in the form of five-six-gonal units.

Basalt is beautiful construction material. In addition, it can be melted and is used for the production of basalt casting. The products have valuable technical qualities: refractoriness and acid resistance.

High-voltage insulators, chemical tanks, sewer pipes etc. Basalts are found in Armenia, Altai, Transbaikalia and other areas.

Basalt differs from other rocks in its high specific gravity.

Of course, it is much more difficult to determine the density of the Earth. And this is necessary to know in order to correctly understand the structure of the globe. The first and quite accurate determinations of the Earth's density were made two hundred years ago.

The density was taken on average from many determinations to be 5.51 g/cm 3 .

Seismology

Science has brought significant clarity to ideas about seismology, studying the nature of earthquakes (from the ancient Greek words: “seismos” - earthquake and “logos” - science).

There is still work to be done in this direction big job. By figuratively the largest seismologist, academician B.B. Golitsyn (1861 -1916),

All earthquakes can be likened to a lantern that lights up for a short time and, illuminating the interior of the Earth, allows us to see what is happening there.

With the help of very sensitive recording devices, seismographs (from the already familiar words “seismos” and “grapho” - I write) it turned out that the speed of propagation of earthquake waves across the globe is not the same: it depends on the density of the substances through which the waves propagate.

Through the thickness of sandstone, for example, they pass more than two times slower than through granite. This allowed us to draw important conclusions about the structure of the Earth.

Earth, By modern according to scientific views, can be represented in the form of three balls nested inside each other. There is such a children's toy: a colored wooden ball consisting of two halves. If you open it, there is another colored ball inside, an even smaller ball inside, and so on.

• The first outer ball in our example is Earth's crust.
• Second - the Earth's shell, or mantle.
• Third - inner core.

The thickness of the walls of these “balls” is different: the outer one is the thinnest. It should be noted here that the earth’s crust does not represent a homogeneous layer of equal thickness. In particular, under the territory of Eurasia it varies within 25-86 kilometers.

As determined by seismic stations, i.e. stations that study earthquakes, the thickness of the earth's crust along the Vladivostok - Irkutsk line is 23.6 km; between St. Petersburg and Sverdlovsk - 31.3 km; Tbilisi and Baku - 42.5 km; Yerevan and Grozny - 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 - 2200 km. The innermost core has a radius of 1200 km. Let us recall that the equatorial radius of the Earth is 6378.2 km, and the polar radius is 6356.9 km.

Substance of the Earth at great depths

What's going on with substance of the Earth, making up the globe, at great depths?
It is well known that temperature increases with depth. In the coal mines of England and in the silver mines of Mexico it 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 that must be descended deep into the Earth for the temperature to rise by 1° is called geothermal stage. Translated into Russian - “the degree of heating of the Earth.” (The word “geothermal” is made up of two Greek words: “ge” - earth, and “therme” - heat, which is similar to the word “thermometer”.)

The value of the geothermal stage is expressed in meters and varies (ranging between 20-46). On average it is taken at 33 meters. For Moscow, according to deep drilling data, the geothermal gradient is 39.3 meters.

The deepest borehole so far does not exceed 12000 meters. At a depth of over 2200 meters, superheated steam already appears in some wells. It is successfully used in industry.

However, in order to draw the right conclusions from this, it is also necessary to take into account the effect of pressure, which also continuously increases as it approaches the center of the Earth.
At a depth of 1 kilometer, the pressure under the continents reaches 270 atmospheres (under the ocean floor 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 temperature will also change with depth. If, for example, basalt melts in factory furnaces at 1155°, then at a depth of 100 kilometers it will begin to melt only at 1400°.

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

This state of matter is characteristic of the second ball of our diagram - the shell of the Earth. Foci of molten mass (magma) directly associated with volcanoes are of limited size.

Earth's core

Shell substance Earth's core viscous, but in the core itself, due to enormous pressure and high temperature, it is in a special physical condition. Its new properties are similar in terms of hardness to the properties of liquid bodies, and in terms of electrical conductivity - with the properties of metals.

In the great depths of the Earth, the substance transforms, as scientists say, into a metallic phase, which is not yet possible to create in laboratory conditions.

Chemical composition of the elements of the globe

The brilliant Russian chemist D.I. Mendeleev (1834-1907) proved that chemical elements represent a harmonious system. Their qualities are in regular relationships with each other and represent successive stages of the single matter from which the globe is built.

• In terms of chemical composition, the earth's crust is mainly formed only by nine elements out of more than a hundred known to us. Among them, first of all oxygen, silicon and aluminum, then, in smaller quantities, iron, calcium, sodium, magnesium, potassium and hydrogen. The rest account for only two percent of total weight all of the listed elements. The earth's crust was called sial, depending on its chemical composition. This word indicated that in the earth's crust, after oxygen, silicon (in Latin - “silicium”, hence the first syllable - “si”) and aluminum (the second syllable - “al”, together - “sial”) predominate.
• There is a noticeable increase in magnesium in the subcortical membrane. That's why they call her sima. The first syllable is “si” from silicium - silicon, and the second is “ma” from magnesium.
• The central part of the globe was believed to be mainly formed from nickel iron, hence its name - nife. The first syllable - "ni" indicates the presence of nickel, and "fe" - iron (in Latin "ferrum").

The density of the earth's crust is on average 2.6 g/cm 3 . With depth, a gradual increase in density is observed. In the central parts of the core it exceeds 12 g/cm 3, and sharp jumps are noted, especially at the boundary of the core shell and in the innermost core.

Large works on the structure of the Earth, its composition and distribution processes chemical elements in nature were left to us by outstanding Soviet scientists - Academician V.I. Vernadsky (1863-1945) and his student Academician A.E. Fersman (1883-1945) - a talented popularizer, author of fascinating books - “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 meteorite analysis. Some meteorites are predominantly iron - that's what they're called. iron meteorites, in others - those elements that are found in rocks of the earth's crust, which is why they are called stony meteorites.

Stone meteorites represent fragments of the outer shells of disintegrated celestial bodies, and iron meteorites represent fragments of their internal parts. Although the external features of stony meteorites are not similar to our rocks, their chemical composition is close to basalts. Chemical analysis of iron meteorites confirms our assumptions about the nature of the central core of the Earth.

Earth's atmosphere

Our ideas about the structure Earth will be far from complete if we limit ourselves only to its depths: the Earth is surrounded primarily by an air shell - atmosphere(from the Greek words: “atmos” - air and “sphaira” - ball).

The atmosphere that surrounded the newborn planet contained the water of the future oceans of the Earth in a vapor state. The pressure of this primary atmosphere was therefore higher than today.

As the atmosphere cooled, streams of superheated water poured onto the Earth, and the pressure became lower. Hot waters created the primary ocean - the water shell of the Earth, otherwise the hydrosphere (from the Greek “gidor” - water), (more details:). The water shell, covering most of the surface of the globe (about 71%), forms a single world ocean.

Exploration of the depths of the ocean has shown that the contours of its bottom are changing. The data that we currently have about the depths of the sea cannot be attributed to the primary ocean, since the oldest sediments are mostly shallow. Consequently, in the most ancient eras of the development of our planet, small bodies of water predominated, but now we observe the opposite ratio.

What does it mean to figure out the deep structure of the Earth? It is necessary to find out the nature of changes in the main characteristics of the lithosphere substance with depth: changes in structure, energy saturation and chemical composition. It is the substance that needs to be studied, because the globe is composed of it, and not just abstract geophysical parameters in the form of seismic wave velocities, differences in magnetic properties, and density. This data is needed to solve various specific practical problems: seismic zoning and others.

To what depth from the surface of the lithosphere can the deep structure of the globe be studied? I would like to reach the center of our planet. But the limitations are caused by the fact that the structure, energy saturation and chemical composition of the substance of the stone shell must be studied. Without obtaining a substance for analysis, it is impossible to determine its structure, energy content and chemical composition.

Therefore, cognition deep structure The Earth is only possible to depths from which it will be possible to obtain samples for analysis. This can be done to the depths of the visible part of the lithosphere, or about 15 km. The most deep wells never reached a depth of 13 km. The Kola superdeep well was drilled almost to this depth. This is the reality of our time.

Everything that is studied deeper than the intervals of possible sampling of a substance by indirect geophysical methods based on the speed of seismic waves, measurements of electrical conductivity, gravity, magnetic properties - in other words, removing the physical characteristics of a substance, must necessarily be certified by samples of the substance from the studied depths, i.e. interpreted geologically . If it is impossible to carry out a geological interpretation of the results of geophysical research, there is no point in carrying out this work to clarify the deep structure of the globe. It is possible and necessary to study the nature of changes in the velocities of seismic waves from the surface to the center of the planet, density and other features, but this will not be knowledge of the deep structure of the Earth in matter. Based on the results of such measurements, it is impossible to talk about the peridotite mantle, the basalt layer of the earth's crust, as well as about the earth's crust, mantle and core in their material terms.

The deep structure of the lithosphere begins below its surface. Geological map shows geological structure area on the day surface. It is not for nothing that a geological map shows the age of rocks (usually bedrock) that come to the surface. To find out the geological structure in volume or depth, geological sections are built.

From the day surface to the lower boundary of the observed part of the lithosphere, the structure of the rocky shell of the globe is as follows.

The basic laws of the composition of the visible part of the deep structure of the lithosphere are formulated in Chapter II. Basic geological laws. Their essence is that the structure becomes more and more coarse-crystalline with depth, the energy saturation decreases, the chemical composition changes: the content of aluminum, iron, magnesium and calcium oxides decreases with depth and silica increases. When quartzite is formed, the presence of not only aluminum, iron, magnesium and calcium oxides, but also sodium and potassium oxides decreases to zero.

Consequences from these laws. Below granite and quartzite there cannot be rocks with an energy saturation greater than that of granite and quartzite. Below granite and quartzite there cannot be rocks with a content of iron, magnesium and calcium oxides greater than that of granite. Below granite and especially quartzite there may be a substance made of silicon oxide.

History of views on the deep structure of the Earth

The widespread development of limestone in Greece, which caused the manifestation of karst, led to the formation of numerous underground caves. This allowed the ancient Greeks to talk about the presence of voids and channels in the Earth. Such ideas about the structure of the globe, widespread throughout our planet, lasted until the beginning of the 19th century, or more than two thousand years.

In 1522, upon completion of El Cano's first trip around the world, begun by F. Magellan, the spherical shape of our planet was proven.

Observing the Sun in 1609 with the help of his second telescope with a magnification of 32 times, G. Galileo (1564-1641) saw dark spots on it. They were taken as evidence of the cooling of the star, although prominences, on the contrary, indicate the activity of the Sun, flares on it. Based on this conclusion, which was not obtained by studying earthly matter, R. Descartes (1596-1650) in the first half of the 17th century. proposed a completely new explanation of the deep structure of the Earth, basically preserved to this day.

He suggested that the Earth was first a hot star, like the Sun, but small in size. Therefore, the cooling of the Earth occurred at a faster rate than the Sun. Cooling led to the appearance on its surface dark spots. With further cooling and interaction of particles of matter, other shells were formed. In the center of the globe, according to R. Descartes, there is a fiery core, folded solar material. It is surrounded by a dense shell of dark sunspot matter. Behind it is a shell in which metals are born. Above is a water shell, then an underground cavity (a shell with numerous voids) filled with air. The uppermost surface shell surrounded by air.

The idea of ​​R. Descartes in the form of the hypotheses of plutonism and Kant-Laplace received the right to citizenship in geology and in general in natural science only two hundred years later, since during the period of its formation it sharply did not correspond to religious ideas about the creation of the Earth and was not accepted by scientists.

By the end of the first quarter of the 19th century. In natural science, the idea of ​​the emergence of the Earth from a hot gaseous nebula, which is currently called the Kant-Laplace hypothesis, has been established. All inner part The globe was assumed to be molten, covered on top with a solid cooling crust - the earth's crust up to 10 miles (16 km) thick. The earth's crust was divided into two parts, lying one on top of the other. Its lower half came from solidified molten material preserved in the interior of the planet. It was called the fiery crust or plutonic crust. It is composed of plutonic rocks: granites, syenites, porphyries, gneisses, marbles, mica schists, etc. The destruction of its material on the surface and the removal of the resulting debris into the seas led to the formation of layers of clays, sandstones and limestones, which formed the outer aquatic or neptunian crust.

Meanwhile, half a century ago, the Neptunists explained the same observed section of the rocky shell of the globe from clays and sands on the surface to granite at depth in a different way, opposite to the Plutonists.

A.G., who in 1775 occupied the department of mineralogy at the Frenberg “Mining School” in Saxony. Werner (1750-1817) in place of geology - a science that consisted in bold hypotheses of the origin of the Earth, proposed a new science - geognosy, the main objective which was in the knowledge of the composition, structure and location of the mineral strata that make up the visible part of the stone shell of the globe. However, he was unable to deviate from the generally accepted sequence of thinking: first the origin of the Earth, then its structure. This can be seen from the order in which the tasks of geognosy are listed, indicated by A.G. Werner.

Initially, it is necessary to find out what relation the Earth has to other celestial bodies, and what it is in the Universe. Such a comparison will allow us to draw a conclusion about what happened to our planet during its existence, identifying the reasons for the transformations that took place with it.

Find out the influence of organic (ore) bodies on the solid part of the globe.

Find out the influence of atmospheric bodies on the solid part of the globe.

Consider the formative (creating) and destructive forces acting on the globe, i.e. water and fire, and the results of the actions of these forces.

Explore the most important natural changes that took place in different times with the globe, especially in chronological order, i.e. which of them were earlier and which were later.

In conclusion, it is necessary to consider in detail the rocks that make up the solid part of the globe. Their study should be carried out in the order in which they “follow their origin,” which will make it possible to divide them into different types according to the method of formation.

From the position of induction, the tasks of natural scientific research should be listed in reverse: first, study the composition and structure of the lithosphere, then the processes that led to the formation of rocks. It is generally impossible to divide rocks by origin, because they do not contain signs of origin. The program for studying the rocky shell of the Earth, proposed by A.G. Werner, is still in progress.

Considering in nature the sequence of bedding of rocks that make up the solid part of the globe, Neptunists assigned the main place in it to clayey shale, which down the section gradually turns into mica shale, consisting of quartz and mica. The oldest mica slate (lying below simple slate) already contains an admixture of feldspar. Through it, it turns into gneiss, and that into granite of a holocrystalline structure. All these breeds were attributed chemical origin by crystals falling out of the water.

Upward, the clay shale gradually turns into gray wacky shale - argillite, which is the oldest known rock of mechanical deposition of the products of destruction of chemical rocks. There is no doubt about the aquatic origin of sands and clays. This can be observed directly in nature.

The general conclusion was that all observed rocks were of aqueous origin. Hence the hypothesis of neptunism. It has been reliably established that the upper part of the sediments known on Earth: clays, sands, sandstones, limestones, arose from water. These aqueous-sedimentary rocks gradually grade into the oldest known formations, with phyllites often interbedded with shales and gneisses. There is no boundary between two such strata.

The famous Neptunist D. de Voisin wrote that he never had to walk more than a few miles along an outcrop of granite without encountering, in one place or another, its transition into gneiss or micaceous schist. In almost all mountain ranges, continued D. De Voisin, one can see how this shale, in turn, turns into clayey (roofing) shale, in which there are then layers of coal with imprints of plants. The shale then begins to become interbedded with layers of rock containing the remains of marine organisms. One can see a desire not to contradict the biblical reasons for which God created plants on the third day, and sea animals later, on the fifth day.

Granites were considered the most ancient, or primary Neptunists. The Scottish naturalist J. Getton (1726-1797), while studying the beautifully exposed sections of Scotland, doubted the sedimentary (water) origin of granite. At first he had theoretical reasoning. The observed random arrangement of quartz, feldspar and mica that compose granite could not have occurred if this rock had been formed by crystallization of salts from sea ​​water, as the Neptunists claimed. The solubility in water of the main minerals of granite is different, therefore in nature in this case monomineral layers of quartz, feldspar and mica should be observed. The crystalline structure of granite from chaotically arranged minerals indicates their crystallization from molten material. Therefore, there must be veins of granite in the overlying layers.

To test his theoretical constructs, J. Getton went to the Grampian Mountains to investigate “the line of connection of granites and the layered masses overlying them.” At Glen Tilt in 1785 he saw veins branching from a large body of red granite, passing through black micaceous slate and limestone. Confirmation of theoretical assumptions about the molten primordial nature of granite aroused such enthusiastic joy in J. Getton that the guides who were with him, according to his biographer, thought that he had discovered a silver or gold mine.

The Neptunists' ideas about the watery origin of granite were dealt an irreparable blow. The molten nature of granite paved the way for the next hypothesis of geology - plutonism. The theoretical basis for it was the Kant-Laplace hypothesis of the formation of the Earth from a hot fireball. As the globe cooled, it became covered on top with a solid cooling crust—an crust about 10 miles (16 km) thick. The inner part below was assumed to be molten. This is how the deep structure of the Earth was seen in the first half of the 19th century.

As can be seen, the ideas of Neptunists and Plutonists on the deep structure and origin of the rocks that make up the globe were opposite. Such a construction of explanations in science is unacceptable; it violates one of the main features of science - acceptability. Back in 1913, N. Bohr formulated the principle of correspondence, according to which any newer (general) hypothesis must include an older hypothesis. The old hypothesis is obtained from the new one for certain values ​​of the parameters that determine it, i.e., it is a special case of the new (general) hypothesis. If this is not observed, as can be seen from the example of the lack of continuity of plutonic ideas from neptunian ones, then the new hypothesis, in our case - plutonism, has no right to exist. By the way, the natural scientific model of geology, which considers lava as a water-silicate solution, and recrystallization as the transition of substances into solution, reaching saturation, to some extent has in common with the ideas of the Neptunists.

It should be noted that there should be no hypotheses in natural sciences at all. I. Newton spoke about this. Talking about hypotheses in natural science is a reflection of mathematical, deductive thinking at its core: axiomatic constructions or empirical knowledge, then observations to search for illustrative material to confirm them. This is necessary to clarify the origin of what is being studied, which is perceived as the researcher sees it. In principle, these are religious aspirations.

The goal of natural science is the opposite: to discover the laws of structure and functioning natural phenomena and objects, deducing consequences from them. This is achieved only by inductive thinking: from the signs of objects and phenomena to concepts, the comparison of which leads to the law. Laws have no exceptions and therefore do not allow for opinions or hypotheses. Cognition is carried out by creating models of the real world, which is not directly observed by people through their senses. The real world is the absolute truth. The model will never be a complete correspondence of real phenomena or objects of nature, so the question of their origin is not raised. You can’t figure out the genesis of something you haven’t fully figured out.

Therefore, it is not surprising that the factual (please remember that not interpretive) material from such sciences as physics and seismology did not confirm the geological consequences of the Kant-Laplace hypothesis, based on deduction.

First of all, physicists doubted the possibility of the formation of a solid earth's crust above the molten deep shell. According to S.D. Poisson (1781-1840), the solidification of the initially molten Earth had to begin from its center. Based on its enormous size, the Earth could not immediately be completely covered evenly with a cooling crust, which in any case had to be crushed by the seething primary melt into separate blocks. The solid blocks that appeared as the surface of the globe cooled, being heavier than the melt, were forced to sink down. At depth they melted, lowering the temperature of the planet's interior. Gradually, subsequent solid blocks reached the center of the Earth, and from there the process of complete solidification spread to the earth's surface. The earth's crust could not theoretically have arisen! This is an initially false, unscientific term, which, however, is used in geology even now, making it unscientific. Therefore, in the natural science model of geology, the term “earth’s crust” is not used, except in historical terms.

The complete solidity of the globe was evidenced by physicists’ data on the influence of the Moon’s gravity on it. It turned out that the ebb and flow of tides arising under the influence of the Moon manifests itself not only in the hydrosphere, causing periodic fluctuations in sea level, but also in the solid part of the planet. Minor vibrations of the earth's surface from such tides indicated the greater elasticity of the substance of the globe, which would have been impossible in the liquid state of its interior.

Originated in the second half of the 19th century. seismology has shown that longitudinal (compression and tension) and transverse (shear) waves propagate from earthquake sources to depths of three thousand kilometers. Transverse deformations with disruption of the continuity of the medium are possible only in solids. In liquids and gases they are extinguished (from a modern point of view due to the high energy saturation of gases, the atoms in which constantly move at speeds of hundreds of meters per second, and liquids in which the molecules also do not stand still). It turned out that there was no molten shell inside the globe, and there was no reason to talk about the earth’s crust or molten core. But they acted contrary to this.

It was accepted that the Earth was first molten and then cooled. Of course, there were no grounds for such a conclusion, and according to modern data (the absence of pre-life time, the presence in the most ancient rocks of 4 billion years of age of the remains of filamentous algae, cell from cell, living from living), it is generally false. Therefore, all consequences regarding the deep structure of our planet from this false idea contradict the laws of physics and chemistry, being unscientific.

It was believed that even at the molten stage, the earth's matter was divided according to density. Heavy metals sank down to the center of the planet, forming an iron-nickel core. Naturally, light elements floated up (silicon - silicium and aluminum - Si + Al), from which the granite earth's crust - sial - arose. An intermediate position is occupied by sima (Si+Mg), which is a basaltic subcrustal substance from which basaltic magma is melted for volcanic eruptions. Such terms, which are still used today: iron-nickel core, sima and sial, were proposed at the beginning of the 20th century. Austrian geologist E. Suess (1831-1914). They also used data on meteorites.

Why is the word “term” used and not “concepts”? The application of the concept implies the presence of necessary and sufficient features of objects that characterize the properties of these objects. Give at least one sign or property of an iron-nickel core, sima or sial according to their material composition. There is none of them. Why? Because there is no iron-nickel core, sima and siali in nature. Indeed, even when they appeared, the terms “sima” and “sial” contradicted the basics of chemistry. Since sima (basalt) was placed below siali (granite), they meant that magnesium is heavier than aluminum (they share silicon). But the density of magnesium is 1.7 g/cm3, while that of aluminum is 2.7 g/cm3. The serial number of magnesium in the Periodic Table of Chemical Elements D.I. Mendeleeva 12, atomic mass 24.312, aluminum - 13 and 26, 9815, respectively, silicon - 14 and 28.086. The heaviest of them is silicon. It is 70% in granite, and only 50% in the underlying basalt. Complete nonsense.

Granites were called sial because they contain a lot of aluminum, and sima (basalt) has less of it. In fact, it's the other way around! In granite there is 14.30% alumina, and in basalt it is more than two percent higher - 16.48%.

At the beginning of the 20th century. The sima placed under the earth's crust (sial) became known as the amorphous basalt layer. It was isolated as a source of energy and matter for volcanoes. It was believed that basaltic magma arises from the basalt layer when pressure decreases from a crack during an earthquake. However, at the same time the American geologist N.L. Bowen (1887-1956) showed that a crack cannot reduce the pressure of the overlying strata, since it does not reduce the mass of the layers. It turns out that melt cannot be obtained at depth from an energy-saturated basalt layer.

Second objection of N.L. Bowen against the participation of the basaltic layer in the production of basic (basaltic) magma was that with partial melting of the substance of the basaltic layer, the chemical composition of the resulting melt would not be basaltic, but more acidic, for example, andesitic, with a higher content of silicon oxides and alkali metals and less - refractory oxides of magnesium, iron and calcium. Basalt could only be obtained by instantaneous complete melting of the basalt layer, which is impossible to do. Therefore, reasoned N.L. Bowen, if basaltic magma is formed at depth, then below the basalt layer there should be a layer with a higher content of magnesium, iron and calcium oxides than in basalt. Peridotite, an ultramafic rock, meets this requirement. Below the basaltic layer (it is unclear to the one left behind, because it was isolated to obtain basaltic magma, but it is impossible to obtain it from it), no longer needed to obtain basaltic melt and therefore included in the composition of the earth’s crust (basaltic magma rises from under the crust), a peridotite layer composing the upper part of the mantle was identified.

Why did crystalline peridotite melt? After all, there is less potential energy in it than in the overlying amorphous basalt layer. American geologist J. Burrell in 1914, below the upper mantle, identified the asthenosphere - a zone of highly heated semi-molten material, i.e., semi-finished melt. It provided energy for the emerging basaltic magma. It turned out that peridotite, as a source of matter and energy for magma, is crystalline in structure and at the same time semi-molten! Absurd!

The separation of the asthenosphere indicated a return to the idea of ​​the primary nature of molten matter in the bowels of the globe, which was professed by geologists in early XIX V.

This was the formation of the currently generally accepted deep structure of the solid part of the Earth from the earth's crust (granite and basalt layers), the mantle, the upper part of which is peridotite up to the asthenosphere, and the core. The earth's crust + upper mantle began to be called the lithosphere, i.e., the rock shell, because the plastic asthenosphere lies below. However, signs of the lithosphere were not reported, because they do not exist, just as there is no earth’s crust and mantle in material (geological) terms. If they are distinguished by the speed of seismic waves, then these are geophysical concepts. They have nothing to do with geology.

In natural science, the globe is usually divided into an atmosphere - a gas shell, a hydrosphere - a water shell, a biosphere - a shell of life, and a lithosphere - a rock shell. It is in this understanding that the concept of lithosphere is used in the natural science model of geology, as a synonym for the stone shell.

But the absurd situations with the generally accepted deep structure of the globe did not end there. At the beginning of the second half of the 20th century. geologists, having compared the chemical compositions of peridotite and basalt (which prevented this from being done earlier when it was proposed to obtain basalt from peridotite), saw that it was impossible to obtain basalt from peridotite. Peridotite contains too little aluminum, sodium, potassium, barium, uranium, thorium and many other chemical elements for partial melting to produce basaltic magma. In peridotite there is only 4.72% Al 2 O 3, 0.73% Na 2 O, 0.38% K 2 O, and in basalt there are almost four times more: 16.48%, 2.78% and 1. 24%. The content of uranium and thorium in basalt is two orders of magnitude higher than that in peridotite.

Based on ideas about the melting of basaltic magma under the crust, Australian geologist A.E. Ringwood concluded that peridotite is not the source of basaltic magma, but serves as a remnant of its melting from the underlying layer, which has a primitive primary composition. The substance of this hypothetical, unseen layer is composed of pyroxenes and olivine, and is therefore called pyrolite.

In a word, the deeper we go, the fewer questions will arise. This is not so, the absurdity is increasing more and more. For example, with the release of pyrolite, a violation of a physical law occurred: in a gravitational field, a heavy substance cannot lie above a lighter one. The section of the upper mantle is assumed to be as follows: a peridotite layer and below it a pyrolite layer. Peridotite is a heavy remnant of pyrolite, supposedly abandoned by lighter basalt. In this case, the peridotite would simply fall into the pyrolite, and there would be no peridotite layer of the upper mantle.

Transmission of the globe by seismic waves arising during earthquakes confirmed the division of the rocky part of our planet into shells with different speeds of passage of seismic waves. The upper shell was identified as the earth's crust, the middle shell as the mantle. The central part was defined as the core.

The thickness of the earth's crust on the continents turned out to be from 40 to 70 km, and in the oceans only 6-8 km. The lower boundary of the earth's crust and the upper boundary of the mantle is taken to be the region of an abrupt increase in the velocity of longitudinal seismic waves from 7.5 to 8.2 km/s. This area was named the Mohorovicic section (Moho, M), in honor of the Yugoslav seismologist A. Mohorovicic (1857-1936), who discovered such a sharp increase in wave speed in 1909 (at that time Yugoslavia did not yet exist). According to the speed of passage of seismic waves, the earth's crust is divided into two layers: the lower, with velocities of 7-7.5 km/s, and the upper, in which the velocities are within 6-6.5 km/s.

When they began to find out in which specific rocks seismic waves have such values, it turned out that in basalt their speed is 7-7.5 km/s, and in granite - 6-6.5 km/s. The result was confirmation of the previously stated division of the earth's crust into lower basalt and upper granite layers (Fig. 9). A seismic wave propagation speed of 8.2 km/s was determined in peridotite.

But basalt cannot exist at depths of 10-70 km. There it recrystallizes into amphibolite, the speed of seismic waves in which is higher than in basalt, and then into granite at a lower speed. Peridotite cannot be found under granite either. So the confirmation by seismology (geophysics) of the structure of the solid part of our planet from the earth’s crust with granite and basalt layers on the continents, basalt in the oceans and peridotite upper mantle is apparent.

Rice. 9.

Let's consider where, based on the characteristics of the chemical composition, structure and energy saturation in the lithosphere, bodies of amorphous basalt and fine-crystalline peridotite can occur? To do this, we first present once again the chemical composition of the layered shell substance that composes the surface of the stone shell, and granite, the deepest, together with quartzite, from the directly observed rock.

It can be seen that as rocks sink, accompanied by recrystallization, their chemical composition changes: the content of aluminum, iron, magnesium and calcium oxides decreases, and the content of silicon, sodium and potassium oxides increases.

Now I provide information on the chemical composition of basalt and peridotite.

Basalt with an amorphous structure and high energy saturation can be found where amorphous rocks are common in the lithosphere, i.e. on its surface. Indeed, basalt arises and exists only on the surface of the stone shell. And according to the characteristics of the chemical composition, basalt should lie higher than granite and layered shells, because it contains more oxides of aluminum, iron, magnesium and calcium and less oxides of silicon and potassium than they do.

Bodies of peridotite as a fine-crystalline rock can be found in the lithosphere only among bodies of fine-crystalline rocks, the most common of which are crystalline schists. This is how it actually is, and peridotite bodies in granites have not been found anywhere in the world. Chemical composition peridotite is specific due to the very high content of magnesium and calcium oxides, indicating that this rock is formed when the rising basaltic solution is freed from excess oxides of these metals.

The very first test of the generally accepted deep structure of the lithosphere on the continents by drilling the Kola superdeep well did not confirm it. The well was laid for scientific purposes to open a basalt layer at a depth of 7 km, which, according to geophysical data, is closest to the surface in this area. The speed of seismic waves there in rocks was determined to be 7-7.5 km/s. In the overlying rocks it was 6-6.5 km/s - granite layer.

In fact, the section uncovered by the well turned out to be opposite to the design one: to a depth of 6842 m, sandstones and tuffs with bodies of dolerites (cryptocrystalline basalts) are widespread, and below - gneisses, granite-gneisses and, less commonly, amphibolites.

The most important thing about the results of drilling the Kola superdeep well is that they not only refute the generally accepted opinion about the structure of the upper part of the lithosphere, but that before they were obtained it was impossible to talk at all about the material structure of these depths of the globe. At the same time, the results of drilling the Kola superdeep well completely confirmed the section of the visible part of the lithosphere from loose and cemented clastic and clayey, and then crystalline rocks, known to people since the middle of the 18th century. (I. Lehman, J. Arduino, A.G. Werner, etc.) and ignored by modern geology. It is this section of the lithosphere that underlies the construction of a natural scientific model of geology.