Volcanoes are individual hills above channels and cracks in the earth’s crust, along which eruption products are brought to the surface from deep magma chambers. Volcanoes usually have the shape of a cone with a summit crater (from several to hundreds of meters deep and up to 1.5 km in diameter). During eruptions, a volcanic structure sometimes collapses with the formation of a caldera - a large depression with a diameter of up to 16 km and a depth of up to 1000 m. As the magma rises, the external pressure weakens, associated gases and liquid products escape to the surface and a volcanic eruption occurs. If ancient rocks, and not magma, are brought to the surface, and water vapor formed during heating predominates among the gases groundwater, then such an eruption is called phreatic.

Active volcanoes include those that erupted in historical times or showed other signs of activity (emission of gases and steam, etc.). Some scientists consider active volcanoes that are reliably known to have erupted within the last 10 thousand years. For example, the Arenal volcano in Costa Rica should be considered active, since volcanic ash was discovered during archaeological excavations of a prehistoric site in this area, although for the first time in human memory its eruption occurred in 1968, and before that no signs of activity were shown.

Volcanoes are known not only on Earth. Images taken from spacecraft reveal huge ancient craters on Mars and many active volcanoes on Io, a moon of Jupiter.

Distribution of volcanic activity

Distribution of volcanoes over the surface globe is best explained by the theory of plate tectonics, which states that the Earth's surface is made up of a mosaic of moving lithospheric plates. When they move in the opposite direction, a collision occurs, and one of the plates sinks (moves) under the other in the so-called. subduction zone, where earthquake epicenters are located. If the plates move apart, a rift zone forms between them. Manifestations of volcanism are associated with these two situations.

Subduction zone volcanoes are located along the boundaries of moving plates. The oceanic plates that form the floor of the Pacific Ocean are known to subduct beneath continents and island arcs. Subduction areas are marked in the topography of the ocean floor by deep-sea trenches parallel to the coast. It is believed that in zones of plate subduction at depths of 100-150 km, magma is formed, and when it rises to the surface, volcanic eruptions occur. Since the plunging angle of the plate is often close to 45°, volcanoes are located between the land and the deep-sea trench at a distance of approximately 100-150 km from the axis of the latter and in plan form a volcanic arc that follows the contours of the trench and coastline. There is sometimes talk of a “ring of fire” of volcanoes around the Pacific Ocean. However, this ring is intermittent (as, for example, in the region of central and southern California), because subduction does not occur everywhere.

Rift zone volcanoes exist in the axial part of the Mid-Atlantic Ridge and along the East African Rift System.

There are volcanoes associated with “hot spots” located inside plates in places where mantle plumes (hot magma rich in gases) rise to the surface, for example, the volcanoes of the Hawaiian Islands. It is believed that the chain of these islands, extending in a westerly direction, was formed during the westward drift of the Pacific Plate while moving over a “hot spot.”

Now this “hot spot” is located under the active volcanoes of the island of Hawaii. Towards the west of this island, the age of the volcanoes gradually increases.

Plate tectonics determines not only the location of volcanoes, but also the type of volcanic activity. The Hawaiian type of eruptions predominates in areas of “hot spots” (Fournaise volcano on Reunion Island) and in rift zones. Plinian, Peleian and Vulcanian types are characteristic of subduction zones. There are also known exceptions, for example, the Strombolian type is observed in various geodynamic conditions.

Volcanic activity: recurrence and spatial patterns.

Approximately 60 volcanoes erupt annually, and about a third of them erupted in the previous year. There is information about 627 volcanoes that have erupted over the past 10 thousand years, and about 530 in historical time, and 80% of them are confined to subduction zones. The greatest volcanic activity is observed in the Kamchatka and Central American regions, with quieter zones in the Cascade Range, the South Sandwich Islands and southern Chile.

Volcanoes and climate . It is believed that after volcanic eruptions, the average temperature of the Earth's atmosphere drops by several degrees due to the emission of tiny particles(less than 0.001 mm) in the form of aerosols and volcanic dust (in this case, sulfate aerosols and fine dust enter the stratosphere during eruptions) and remain so for 1-2 years. In all likelihood, such a decrease in temperature was observed after the eruption of Mount Agung on Bali (Indonesia) in 1962.

Sedimentary layers contain much less traces of volcanic activity than would be expected from geological history, which, according to scientists, is billions of years old. Volcanic emissions include lava, ash, slag, and more. Eruptions can be minor, or they can be large, accompanied by the ejection of many cubic kilometers of rock. Several years ago, a geologist, based on a very conservative estimate that all the world's volcanoes emit an average of one cubic kilometer of volcanic material per year, calculated that in 3.5 billion years the entire Earth would be covered with a seven-kilometer layer of such material. Since its actual share is quite small, the scientist concluded that the intensity of volcanic activity should fluctuate 22 .

Currently, Earth's volcanoes appear to emit about four cubic kilometers of material per year. Individual large eruptions may be accompanied by significant emissions. Volcano Tambora (Indonesia, 1815) erupted 100-300 cubic kilometers; Krakatau volcano (Indonesia, 1883) - 6-18 cubic kilometers; and the Katmai volcano (Alaska, 1912) - 20 cubic kilometers 23. Calculations including only major volcanic eruptions over four decades (1940-1980) show an average of 3 cubic kilometers per year 24 . This estimate does not take into account the many smaller eruptions that periodically occur in regions such as Hawaii, Indonesia, Central and South America, Iceland, Italy, etc. Experts say that the average volume of volcanic emissions is 4 cubic kilometers per year 25 .

According to the classic work of the famous Russian geochemist A.B. Ronova, the Earth's surface contains 135 million cubic kilometers of sediment of volcanic origin, which, according to his estimates, constitutes 14.4 percent of the total volume of sedimentary rocks 26. Although the figure of 135 million sounds impressive, it is not much compared to the amount of sediment that would have been deposited by volcanic activity over long geological epochs. If current ejection rates are extrapolated over 2.5 billion years, the Earth's crust should contain 74 times more volcanic material than is currently present. The thickness of this volcanic layer, covering the entire earth's surface, would exceed 19 kilometers. The absence of such volumes can hardly be explained by erosion, since it would only transport the products of volcanic eruptions from one place to another. It can also be assumed that a huge amount of volcanic material disappeared as a result of subduction, as evidenced by plate tectonics, but this explanation does not stand up to criticism. Along with the volcanic material, other geological layers containing it would also disappear. However, the geological column containing this volcanic material is still clearly visible throughout the world. Perhaps volcanic activity is not 2.5 billion years old after all.

RAISE OF MOUNTAIN RANGES

The so-called solid ground that we prefer to have under our feet is not as unshakable as we think. Careful measurements show that some parts of the continents are slowly rising, while others are sinking. The world's major mountain ranges are slowly rising at a rate of a few millimeters per year. Precise measurement techniques are used to determine this growth. Scientists estimate that, overall, mountains rise by approximately 7.6 millimeters per year 27 . The Alps in Central Switzerland are growing more slowly - from 1 to 1.5 millimeters per year 28. Studies show that for the Appalachians the rate of uplift is about -10 millimeters per year, and for the Rocky Mountains - 1-10 millimeters per year 29.

I am not aware of any data relating to precise measurements of the rate of rise of the Himalayas, however, due to the fact that tropical vegetation that existed relatively recently was discovered at an altitude of 5000 meters, and the fossilized remains of a rhinoceros, as well as on the basis of overturned layers, scientists conclude that uplift rates of 1–5 millimeters per year (under uniform conditions over long periods). Tibet is also believed to be rising at about the same rate. Based on mountain structure and erosion data, researchers estimate the rate of rise of the Central Andes to be approximately 3 millimeters per year 30 . Parts of the Southern Alps in New Zealand are rising at a rate of 17 millimeters per year 31 . Probably the fastest gradual (not associated with catastrophic events) growth of mountains is observed in Japan, where researchers note a rate of rise of 72 millimeters per year over a 27-year period 32 .

It is impossible to extrapolate the current rapid rate of mountain uplift into the too distant past. At an average growth rate of 5 millimeters per year, mountain ranges would rise 500 kilometers in just 100 million years.

Nor will reference to erosion help us resolve this discrepancy. The rate of uplift (about 5 millimeters per year) is more than 100 times higher than the average rate of erosion that scientists estimate existed before the advent of agriculture (about 0.03 millimeters per year). As stated earlier, erosion is faster in mountainous areas, and its rate gradually decreases as the terrain descends; therefore, the higher the mountains, the faster they erode. However, according to some calculations, in order for erosion to keep up with the so-called “typical rate of uplift” of 10 millimeters per year, the height of the mountain must be at least 45 kilometers 33. This is five times higher than Everest. The problem of the discrepancy between the rate of erosion and the rate of uplift does not go unnoticed by researchers 34 . In their opinion, this contradiction is explained by the fact that we are currently observing a period of unusually intense mountain uplift (something like episodicism).

Another problem for standard geochronology is that if mountains have risen at current rates (or even much slower) throughout Earth's history, then the geological column, including its lower layers, which geologists estimate to be hundreds of millions, if not billions of years, should have risen long ago and disappeared as a result of erosion. However, all ancient sections of the column, as well as younger ones, are well represented in the geological record of the continents. Mountains where unusually high rates of uplift and erosion are observed have apparently not gone through even one cycle involving these processes, although throughout all hypothetical eras there could have been at least a hundred such cycles.

CONCLUSION

The observed rates of erosion, volcanism, and uplift of mountain ranges are perhaps too high for the standard geologic time scale, which allows billions of years for sedimentary strata to emerge and the life forms they contain to evolve. The discrepancies are very significant (see Table 15.3), and therefore they cannot be neglected. Hardly any scientist can guarantee that the conditions that existed on Earth in the past remained constant enough to ensure the same rate of change over billions of years. These changes may have occurred more rapidly or more slowly, but the figures given in Table 15.3 show how great the discrepancies are when we compare contemporary rates with geological time scales. Geologists have put forward various explanations to try to reconcile these data, but their hypotheses are largely based on guesswork.

On the other hand, it can just as well be argued that many of the above processes are too slow for the creation model, according to which the age of the Earth does not exceed 10,000 years. However, this argument does not carry much weight, since the creation model includes a catastrophic, worldwide flood that could increase the rate of each of these processes many times over. Unfortunately, our knowledge of this unique event is too poor for us to make any serious calculations, but recent trends in geological science towards catastrophic interpretations allow us to judge how quickly such changes could occur 35.

Factors that contradict standard geochronology Table 15.3

One can try to reconcile today's high rates of change with geological time by suggesting that in the past these rates were lower or were cyclical. However, calculations show that individual processes should have proceeded tens and hundreds of times slower than now. This is unlikely, given the fact that the Earth of the past was not very different from the Earth of the present, as evidenced by the species of animals and plants found in the fossil record. Fossil forests, for example, needed significant moisture, just like their modern counterparts. Moreover, slower changes in the past appear to contradict the general geological scenario in which the Earth was more active early in its history 36 . Geologists believe that at that time heat flow and volcanic activity were on a much larger scale. Is it possible for evolutionary scientists to turn this model on its head and claim that change is now occurring at a much faster rate? Unfortunately, this trend is completely inconsistent with what we might expect from an evolutionary model. This model assumes an initially hot Earth cooling to a more stable state, and the rate of geological change slowly decreasing over time towards equilibrium.

When we consider modern rates of erosion and mountain uplift, the same question periodically arises: why is the geological column so well preserved if such processes have been occurring for billions of years. However, the current pace of geological change can easily be attributed to the concept of a recent creation and subsequent catastrophic flood. The receding flood waters must have left behind significant parts of the geological column in the form in which they remain to this day. In the context of the Flood, the relatively low rates of erosion, volcanism, and uplift of mountain ranges that we observe today may represent the lingering effects of that catastrophic event.

The current intensity of geological transformations calls into question the validity of the standard geological time scale.

1. Smiles S. n.d. Self-help, chapter 11. Quoted in: Mackay AL. 1991. A dictionary of scientific quotations. Bristol and Philadelphia: Institute of Physics Publishing, p. 225.

2. These and related factors are discussed more fully in: Roth AA. 1986. Some questions about geochronology. Origins 13:64-85. Section 3 of this article, dealing with geochronological issues, needs updating.

3. a) Huggett R. 1990. Catastrophism: systems of earth history. London, New York, and Melbourne: Edward Arnold, p. 232; b) Kroner A. 1985. Evolution of the Archean continental crust. Annual Review of Earth and Planetary Sciences 13:49-74; c) McLennan SM, Taylor SR. 1982. Geochemical constraints on the growth of the continental crust. Journal of Geology 90:347-361; d) McLennan SM, Taylor SR. 1983. Continental freeboard, sedimentation rates and growth of continental crust. Nature 306:169-172; e) Taylor SR, McLennan SM. 1985. The continental crust: its composition and evolution: an examination of the geo-chemical record preserved in sedimentary rocks. Hallam A, editor. Geoscience texts. Oxford, London, and Edinburgh: Blackwell Scientific Publications, pp. 234-239; f) Veizer), Jansen SL. 1979. Basement and sedimentary recycling and continental evolution. Journal of Geology 87:341–370.

4. I.e., Garrels RM, Mackenzie FT. 1971. Evolution of sedimentary rocks. New York: W. W. Norton and Co., p. 260.

5. JudsonS.RitterOF. 1964. Rates of regional denudation in the United States, Journal of Geophysical Research 69:3395-3401.

6. a) Dott RH, Jr.. Batten RL. 1988. Evolution of the Earth. 4th ed. New York, St. Louis, and San Francisco: McGraw-Hill Book Co., p. 155. Other authors using the same estimates: b) Garrels and Mackenzie, p. 114 (note 4); c) Gilluly J. 1955. Geologic contrasts between continents and ocean basins. In: Poldervaart A, editor. Crust of the earth. Geological Society of America Special Paper 62:7-18; d) Schumm SA. 1963. The disparity between present rates of denudation and orogeny. Shorter contributions to general geology. G.S. Geological Survey Professional Paper 454-H.

7. Sparks BW. 1986. Geomorphology. 3rd ed. Beaver SH, editor. Geographies for advanced study. London and New York: Longman Group, p. 510.

8. a) Ahnert F. 1970. Functional relationships between denudation, relief, and uplift in large mid-latitude drainage basins. American Journal of Science 268:243-263; b) Bloom AL. 1971. The Papuan peneplain problem: a mathematical exercise. Geological Society of America Abstracts With Programs 3(7):507,508; c) Schumm (noteGd).

9. Ruxton BP, McDougall 1.1967. Denudation rates in northeast Papua from potassium-argon dating of lavas. American Journal of Science 265:545–561.

10. Corbel J. 1959. Vitesse de L'erosion. Zeitschrift fur Geomorphologie 3: 1 -28.

11. Menard HW. 1961. Some rates of regional erosion. Journal of Geology 69:154–161.

12. Mills HH. 1976. Estimated erosion rates on Mount Rainier, Washington. Geology 4:401–406.

13. OHierCD, Brown MJF. 1971. Erosion of a young volcano in New Guinea. Zeitschrift fbr Geomorphologie 15:12–28.

14. a) Blatt H, Middleton G, Murray R. 1980. Origin of sedimentary rocks. 2nd ed. Englewood Cliffs, N.J.: Prentice-Hall, p. 36; b) Schumm (note 6d).

15. The surface area of ​​our continents is approximately 148,429,000 square kilometers. With an average height of the continents of 623 meters, the volume of their constituent rocks located above sea level is approximately 92,471,269 cubic kilometers. If we assume that the average density of rocks is 2.5, then their mass will be 231171x10 12 tons. If we divide this number by 24108 x 10 6 tons of sediment carried by the world's rivers to the oceans in one year, it turns out that the complete erosion of the continents would occur in approximately 9.582 million years. That is, in 2.5 billion years at this rate of erosion, the continents could be eroded 261 times (2.5 billion divided by 9.582 million).

17. The remains of ancient sedimentary rocks must be very insignificant. All sedimentary rocks (including much of what lies below sea level) must have been repeatedly eroded. The total mass of sedimentary rocks is 2.4 x 10 18 tons. Rivers before agricultural development carried approximately 1 x 10"° tons per year, so the erosion cycle would be equal to 2.4 x 10 18 divided by 10 x 10 9 tons per year, which is approximately 240 million years, or ten complete cycles of sediment erosion in 2 .5 billion years. These are rather conservative estimates; some scientists believe that there have been "three to ten such cycles since the late Cambrian" ([a] Blatt, Middleton, and Murray, pp. 35-38;). eluvium (remnant) of sedimentary rocks per unit time is even more significant in some more ancient periods (for example, Silurian and Devonian) compared to those quite close to modern times (from Mississippian to Cretaceous) (see: [b] Raup DM. 1976. Species diversity in the Phanerozoic: an interpretation. Paleobiology 2:289-297). For this reason, some scientists have suggested two cyclical sequences of changes in the rate of erosion in the Phanerozoic (for example, [with] Gregor SV. 1970. Denudation of the continents. Mature). 228:273-275). This scheme contradicts the hypotheses that due to cyclicity, older sediments of a smaller volume were formed. In addition, our depositional basins are often smaller in deep areas, limiting the volume of the lowermost (oldest) sediments. One might also argue that in the past much more sediments arose from granitic rocks than we now have, and that only a small part of it remains. These precipitation could survive several cycles. Perhaps the most serious problem facing this model is the chemical mismatch between sedimentary rocks and the Earth's granitic crust. Granite-type igneous rocks on average contain more than half as much calcium as sedimentary rocks, three times more sodium and more than a hundred times less carbon. Data and analysis can be found in: d) Garrels and Mackenzie, pp. 237, 243, 248 (note 4); e) Mason W, Mooge SV. 1982. Principles of geochemistry. 4th ed. New York, Chichester, and Toronto: John Wiley and Sons, pp. 44,152,153; f) Pettijohn FJ. 1975. Sedimentary rocks. 3rd ed. New York, San Francisco, and London: Harper and Row, pp. 21, 22; g) RonovAB, Yaroshevsky AA. 1969. Chemical composition of the earth's crust. In: Hart PJ, editor. The earth's crust and upper mantle: structure, dynamic processes, and the ir relation to deep-seated geological phenomena. American Geophysical Union, Geophysical Monograph 13:37-57; h) Othman DB, White WM, Patched J. 1989. The geochemistry of marine sediments, island arc magma genesis, and crust-mantle recycling. Earth and Planetary Science Letters 94:1-21. Calculations based on the premise that all sedimentary rocks arose from igneous rocks produce incorrect results. Calculations based on actual measurements should be used various types precipitation. It is difficult to imagine recyclability between granitic and sedimentary rocks with such a mismatch of basic elements. One of the larger problems is how granitic rocks, which are relatively low in calcium and carbon, can become limestone (calcium carbonate). Moreover, redeposition of sediment in a localized area on a continent does not seem to solve the problem of rapid erosion, since the figures used for calculations are based on the amount of sediment flowing from the continents into the oceans and do not include local redeposition. In addition, usually the main sections of the geological column come to the surface and are eroded in the basins of the world's main rivers. This erosion is especially fast in the mountains, where there is a lot of ancient sedimentary rock. Why are these ancient sediments still there if they are being redeposited?

18. a) Gilluly J, Waters AC, Woodford AO. 1968. Principles of geology. 3rd ed. San _ Francisco: W. H. Freeman and Co., p. 79; b) JudsonS. 1968. Erosion of the land, or what's happening to our continents? American Scientist 56:356-374; c) McLennan SM. 1993. Weathering and global denudation, Journal of Geology 101:295-303; (d) Milliman JD , Syvitski JPM. 1992. Geomorphic/tectonic control of sediment discharge to the ocean: the importance of small mountainous rivers. Journal of Geology 100:525-544.

19. Frakes LA. 1979. Climates throughout geologic time. Amsterdam, Oxford, and New York: Elsevier Scientific Pub. Co., Figure 9-1, p. 261.

20. Daily B, Twidale CR, Milnes AR. 1974. The age of the lateritized summit surface on Kangaroo Island and adjacent areas of South Australia. Journal of the Geological Society of Australia 21(4):387–392.

21. The problem and some general solutions are given in: Twidale CR. 1976. On the survival of paleoforms. American Journal of Science 276:77–95.

22. Gregor GB. 1968. The rate of denudation in post-Algonkian time. Koninklijke Nederlandse Academic van Wetenschapper 71:22–30.

23. Izett GA. 1981. Volcanic ash beds: recorders of upper Cenozoic silicic pyroclastic volcanism in the western United States. Journal of Geophysical Research 868:10200–10222.

24. See list in: Simkin T, Siebert L, McClelland L, Bridge D, Newhall C, Latter JH. 1981. Volcanoes of the world: a regional directory, gazetteer, and chronology of volcanism during the last 10,000 years. Smithsonian Institution Stroudsburg, Pa.: Hutchinson Ross Pub. Co.

25. Decker R, Decker B, editors. 1982. Volcanoes and the earth's interior: readings from Scientific American. San Francisco: W. H. Freeman and Co., p. 47.

26. a) Ronovand Yaroshevsky (note 17g); b) Ronov says 18 percent volcanic material for the Phanerozoic alone; see: Ronov AB. 1982. The earth's sedimentary shell (quantitative patterns of its structure, compositions, and evolution). The 20th V. I. Vernadskiy Lecture, Mar. 12, 1978. Part 2. International Geology Review 24(12): 1365-1388. Volume estimates sedimentary rocks according to Ronov and Yaroshevsky are high in relation to some others. Their conclusions were greatly influenced by the discrepancies in the total calculated thickness: 2500x10 6 years x 4 cubic kilometers per year = 10000x10 6 cubic kilometers divided by 5.1x10 8 square kilometers =. 19.6 kilometers in height.

27. Schumm (note 6d).

28. Mueller St. 1983. Deep structure and recent dynamics in the Alps. In: Nz KJ, editor. Mountain building processes. New York: Academic Press, pp. 181-199.

29. Hand SH. 1982. Figure 20-40. In: Press F, Siever R. 1982. Earth. 3rd ed. San Francisco: W. H. Freeman and Co., p. 484.

30. a) Gansser A. 1983. The morphogenic phase of mountain building. In: Hsb, pp. 221-228 (note 28); b) Molnar P. 1984. Structure and tectonics of the Himalaya: constraints and implications of geophysical data. Annual Review of Earth and Planetary Sciences 12:489-518; c) Iwata S. 1987. Mode and rate of uplift of the central Nepal Himalaya. Zeitschrift for Geomorphologie Supplement Band 63:37–49.

31. Wellman HW. 1979. An uplift map for the South Island of New Zealand, and a model for uplift of the southern Alps. In: Walcott Rl, Cresswell MM, editors. The origin of the southern Alps. Bulletin 18. Wellington: Royal Society of New Zealand, pp. 13-20.

32. Tsuboi C. 1932-1933. Investigation on the deformation of the earth's crust found by precise geodetic means. Japanese Journal of Astronomy and Geophysics Transactions 10:93-248.

33. a) Blatt, Middleton, and Murray, p. 30 (note 14a), based on data from: b) Ahnert (note8a).

34. a) Blatt, Middleton, and Murray, p. 30 (note 14a); b) Bloom AL. 1969. The surface of the earth. McAlester AL, editor. Foundations of earth science series. Englewood Cliffs, NJ.: Prentice-Hall, pp. 87-89; c) Schumm (note 6d).

35. Several examples can be found in Chapter 12.

Chapter 12. Characteristics of various feelings. 4) his behavior, considered as exploratory activity in a situation where the child is on the mother’s lap;

Diuretics. Antipagic drugs. Uterotropic drugs. Agents affecting the contractile activity of the myometrium

Case 17. Investment activity in the Russian economy

Various statements alarming people about the approach of some kind of global geological catastrophe began to appear in the media and in some scientific publications.

The press service of the World Organization for Scientific Cooperation “Science Without Borders” (WOSCO SWB) asked a famous scientist - geophysicist, specialist in the field of seismology and geodynamics, Vice-President of the International Academy of Sciences H&E (Austria, Innsbruck), Academician to comment on the situation Russian Academy Natural Sciences, Doctor of Geological and Mineralogical Sciences, Director of the Research Institute for Forecasting and Study of Earthquakes Elchin Khalilov.

Dear Professor Khalilov, recently a lot of information has appeared in the media about the approaching global natural disaster. Some associate this with the possibility of the so-called polarity reversal or a change in the sign of north and south magnetic poles Earth, others predict catastrophic climate change and global flooding of vast areas of land, while others predict earthquakes, volcanic eruptions and tsunamis of incredible force. Other forecasts are based on the possibility of a huge asteroid passing close to the Earth’s orbit, which, under its gravitational influence, could cause global natural disasters on Earth. What should we really believe? Please comment on this situation.

I have been researching seismic and volcanic activity from the perspective of global geodynamic processes for more than 25 years. All these years of research I have been conducting together with an outstanding scientist of our time, a world-famous Russian geologist, academician of the USSR Academy of Sciences, the Russian Academy of Sciences and many national and international academies, Honorary President of the International Academy of Sciences (health and ecology), Honored Professor of M.V. Lomonosov Moscow State University Viktor Efimovich Khain. But I want to especially emphasize that everything I have said is based on our many years of joint research.

First of all, I would like to note that many of the disturbing factors that you mentioned do exist, but perhaps they are not always correctly interpreted. The fact is that the research we conducted together with famous scientists, academicians V. Khain, Sh. Mekhtiev and T. Ismailzade, made it possible for the first time to establish an unusual modern cyclicity in the manifestations of earthquakes and volcanic eruptions on our planet. It has long been noted that at certain periods of time, as if by a special command, strong earthquakes begin to occur almost simultaneously and volcanoes erupt in various parts planets, then also suddenly there is a lull.

In fact, research results have shown that this cyclicity in the manifestations of strong earthquakes and volcanic eruptions is not at all simple. In particular, it turned out that while earthquakes and volcanic eruptions are activated in some zones (in the Earth’s compression belts), in other zones they subside (in the Earth’s extension belts), then the reverse process occurs, seismic and volcanic activity in the Earth’s compression belts Activity in the Earth's stretch zones decreases and increases.

For geologists, it is obvious that earthquakes and volcanoes are an excellent indicator of tectonic activity on the planet. That is, if earthquakes in the Earth’s compression belts are activated, this means that compression processes on the planet have intensified; if activation occurs in the Earth’s extension zones, this means that extension processes are intensifying.

The results of our research have been recognized as scientific discovery in 2003.

- What comes from this and where are the compression and extension zones of the Earth located?

The Earth's compression and extension belts are planetary, relatively narrow and gigantic areas of volcanic and seismic activity, in which more than 80% of the energy of earthquakes and volcanic eruptions of the world is released. For a better understanding, without going into the wilds of geology, I will explain that the uppermost shell of our planet is divided into giant blocks that move horizontally relative to each other. They are called lithospheric plates. So, almost all the strong earthquakes and volcanoes in the world are concentrated at the boundaries of these plates. Where the plates diverge, processes of extension of the Earth's lithosphere occur, and where they collide, processes of compression occur.

Almost along the central axis of the entire world ocean there are oceanic rift zones - giant faults that reflect the boundaries of lithospheric plates, where they diverge.

It is here that the Earth's lithosphere undergoes stretching and renewal. In some places, these zones also originate on continents, for example, a giant rift zone runs in the meridional direction along the Eastern part of Africa, in the area of ​​Lake Baikal, through Iceland.

The Earth's compression belts are mainly gigantic mountain systems, and in the oceans - deep-sea depressions and bordering ridges of islands, often of volcanic origin. Classic giant compression belts of the Earth are the mountain ranges running along the western part of the continents of North and South America, the Alpine-Himalayan seismic belt - a mountain range starting from the Alpine mountains and reaching the Himalayas, capturing parts of China and India. The Alpine-Himalayan seismic belt includes some countries of the Middle and Near East, countries of Southern and Southeast Europe, the Caucasus, Central Asia and part of Southeast Asia.

If we talk about the young and, perhaps, the most active compression belts of the Earth, these are mainly the countries of the so-called ring of fire.

The “Ring of Fire” is a horseshoe-shaped band of volcanoes and tectonic faults 40 thousand kilometers long, encircling Pacific Ocean, running along the coast of South and North America to southern Alaska, then turning towards Japan, (including Far East Russia), the Philippines and Indonesia and ending in the island area New Guinea, New Zealand and southwest Oceania. It is in the “Ring of Fire” that more than 80% of the approximately one and a half thousand known active volcanoes on the planet are located.

For a better understanding, we have shown a map on which all the zones I have designated are indicated.

- What can we expect in the near future in the regions you indicated?

I really want to reassure readers and say that no increase in seismic and volcanic activity is expected, which I have repeatedly done in many of my statements in past years. But, unfortunately, I cannot do this now, since it is my duty as a scientist to provide objective information to society, to try to predict further development events. Actually, this is the main meaning of seismology and volcanology, otherwise why do these studies need to be done?

It has now become obvious that the Earth should be considered as an integral element of the cosmos, inextricably linked with the processes occurring in it. The famous Russian scientist A.L. Chizhevsky devoted a lot back in the 20s of the last century scientific works studying the influence of solar activity on terrestrial processes of a biological, socio-psychological and geological nature.

Many scientists around the world confirm the fact of the influence of solar activity on the activation of earthquakes and volcanic eruptions, but still there is some ambiguity in these results. In our research with the participation of academicians V. Khain and Sh. Mekhtiev, we were able to discover new aspects in this issue. It turned out that solar activity has a different effect on the activation of earthquakes and volcanic eruptions in different regions of our planet. For example, with an increase in solar activity, the activity of earthquakes and volcanic eruptions in the Earth's compression belts increases, and in extension belts, on the contrary, it decreases.

Moreover, what is especially important is that the higher the amplitude of the solar activity cycle, the higher the seismic and volcanic activity.

At the same time, the non-simultaneity of planetary processes of compression and extension indicates the possibility of periodic changes in the radius of the Earth within a few centimeters, which, in our opinion, is reflected in changes in the angular velocity of its rotation.

The most pronounced cycle of solar activity is considered to be the 11-year cycle. Since the beginning of regular observation of sunspots, 23 cycles of solar activity have been officially recorded, with the 23rd cycle occurring in 2001. Surely experts remember that from the end of 1999 to 2004 there were many catastrophic earthquakes that claimed more than half a million human lives. The year 2007 can be called the year of minimum solar activity, but since 2008 it began to increase again. It would seem, well, what’s unusual here, we’ve gone through 23 cycles before this, well, another one will pass. Unfortunately, the 24th cycle is predicted to be unusual.

For any forecasts, first of all, process models are created. The most accurate model for the formation of sunspots was developed in 2004 by a group of scientists working under the leadership of Dr. Mausumi Dikpati from National Center US Atmospheric Research (NCAR). According to their calculations, the magnetic structures that form the sunspots originate in the region of the Sun's equator. There they are “imprinted” into the plasma and move with it towards the poles. Having reached the pole, the plasma plunges into the star to a depth of about 200 thousand km. From there, it begins to flow back towards the equator at a speed of 1 m/sec. One such circle corresponds to the solar activity cycle - 17–22 years. The researchers called their model the “dynamo transport model.” magnetic flux" We are now at the beginning of the 24th 11-year solar cycle. Having included data on the 22 preceding the 23rd cycle into the model, scientists calculated what the 23rd cycle should be like. The result coincided with what we observed by 98%. Having thus tested their model, the researchers at the beginning of 2006 calculated the 24th cycle of solar activity, the peak of which would be in 2012.

It is predicted that the 24th cycle of solar activity will be 1.5 times more powerful than the previous 23rd. This means that the number and energy of earthquakes and volcanic eruptions during this period will be significantly higher than all previous ones. In addition, we have established that during this period the maxima of solar activity cycles of at least three orders of magnitude will coincide, which should lead to a kind of energy resonance.

Our studies have shown that there is some inertia in the increase in seismic and volcanic activity in relation to solar activity. That is, if the peak of solar activity occurs in 2012, then the maximum of seismic and volcanic activity will occur in 2012–2015. I would like to especially emphasize that this conclusion is confirmed by the cyclicities we have established in the activity of earthquakes and volcanic eruptions in the compression belts of our planet, the peaks of which also occur during this period. In a word, from 2012 to 2015 it will be, to put it mildly, “a bit hot” on our planet.

- Which countries, in your opinion, will be most exposed to natural disasters?

I’ll start, first of all, with the “ring of fire” - I listed the regions included in this zone above. The Ring of Fire will live up to its name, for it is there that the largest number of the world's largest active volcanoes are located.

The strongest earthquakes will also occur there. In second place in terms of seismic activity (but not volcanic activity), I would put the Alpine-Himalayan seismic belt, and in it, the most dangerous territories are in the northwestern part of India, China, Pakistan and Afghanistan, the southern part of the republics Central Asia, Iran, Caucasus countries, Turkey, Italy, Greece. In Italy there is also a high probability of the activation of the volcanoes Etna and Vesuvius on its territory during the noted period. Along with these areas, seismic activity is expected to increase at a similar level along the entire western coast of North and South America.

- You have listed so many territories that it becomes creepy. Where will it not shake so much?

Of course, there are many areas that will not be affected by seismic and volcanic activity - these are the so-called intraplate zones or platforms.

For example, this is the entire central and Northern part Russia, the eastern part of Scandinavia, central and northern parts of Europe, Australia, Greenland, the entire western part of the African continent, the eastern part of South and North America and the entire northern part of North America. So, you can definitely move to these zones. But I want to warn you that some of them may be subject to natural disasters of a different nature.

- Well, what are you doing? last hope are you taking away? What other surprises does nature have in store for us?

I would like to remind you that at the beginning of our conversation you mentioned alarming information regarding a possible change in the signs of the Earth’s magnetic poles.

So, I would like to dwell on this in a little more detail. The fact is that many often identify the magnetic and geographic poles of the Earth. But in fact, these are completely different concepts and their location does not coincide.

The geomagnetic field is not so constant and it changes from time to time.

The role of geo magnetic field for the existence and development of life on Earth can hardly be overestimated, because the force lines of the Earth’s magnetic field create a kind of magnetic screen around the planet that protects the Earth’s surface from cosmic rays and the flow of charged high-energy particles that are destructive to all living things.

The latest data on the state of the Arctic magnetic pole (moving towards the East Siberian world magnetic anomaly through the Arctic Ocean) showed that at the beginning of 2002, the drift speed of the north magnetic pole increased from 10 km/year in the 70s to 40 km/year in 2001.

In addition, according to IZMIRAN (Russia, Moscow), there is a drop in the strength of the earth’s magnetic field, and quite unevenly. According to scientists from IZMIRAN, the acceleration of the movement of the poles (on average by 3 km/year) and their movement along the corridors of magnetic pole inversion (more than 400 paleoinversions made it possible to identify these corridors) leads to the assumption that this movement of the poles should not be seen as an excursion , but a reversal of the Earth’s magnetic field.

In 2007 at the Center space research Denmark, after analyzing the latest data obtained from a satellite monitoring the Earth's magnetic fields, came to disappointing conclusions. According to Danish scientists, intensive preparation of the Earth's geomagnetic field for the inversion of magnetic poles is taking place and this may happen much earlier than expected.

But I would like to especially note that geophysicists cannot help but be alarmed by the fact that the movement of the magnetic poles has accelerated almost fivefold over the past four decades. What underlies the movements of the magnetic poles? First of all, these are processes occurring in the Earth's core. If the magnetic poles moved much faster, this meant that the energy in the Earth’s core began to increase significantly. At the same time, as is known, it is the deep energy processes in the Earth’s core that set in motion giant convective flows in the mantle, which, in turn, move lithospheric plates, at the boundaries of which earthquakes and volcanic eruptions occur.

Consequently, the fivefold acceleration of the movement of the magnetic poles indicates that the speed and scale of energy processes in the bowels of our planet have increased sharply, which corresponds to our conclusions about the approach of a period of unusually high levels of seismic and volcanic activity.

As for climate change, it will be a consequence of the above processes.

What do you mean by this, that global climate change will be associated with earthquakes and volcanic eruptions?

You know, in the last decade, a lot of work has been devoted to global climate change and, in most of them, the main role in global warming is given to man-made activities. But is this really so?

In our works, together with Viktor Efimovich Khain, we carried out detailed comparisons of graphs of the cyclicity of volcanic activity over the past 150 years and average annual temperature changes on our planet. So, the result exceeded all our expectations. Firstly, in terms of shape and periods of cycles, the graphs almost repeat each other. But, on the other hand, the cycles on the graph of increasing temperatures are about 15 years behind the cycles of increasing volcanic activity. This delay is based on a cause-and-effect relationship between these two processes.

What is the mechanism of cause-and-effect relationship between volcanic activity and temperature changes on Earth? An increase in the number of volcanic eruptions leads to an increase in the entry of volcanic gases into the atmosphere, which contribute to an increase in the greenhouse effect and, as a consequence, lead to an increase in atmospheric temperature. From 1860 to 2000, the number of volcanic eruptions increased by 80%.

Almost doubling the average annual number of volcanic eruptions should lead to a doubling of volcanic gases entering the atmosphere and, above all, CO2, which plays a leading role in the formation of the greenhouse effect and an increase in the average annual temperature on Earth.

Based on the patterns we have established, an attempt has been made to make a long-term forecast of both changes in the volcanic activity of the Earth’s compression belts and global changes in the average temperature on our planet until 2060.

A global increase in the average annual temperature on Earth, against the background of minor variations, according to the results of our research, will be observed from 2020 to 2050.

An increase in average annual temperature, naturally, will be accompanied by melting ice, an increase in the level of the world's oceans and precipitation falling on the Earth.

Do you want to say that even if people are saved from earthquakes and volcanic eruptions, they will be overtaken by another disaster - global flooding of gigantic land areas?

I would not like to be unfounded, so I will resort to the help of official data from the Intergovernmental Commission on Climate Change (IPCC) http://www.ipcc.ch/ As follows from the reports of this commission, “greenhouse” warming is coming, as a result of which they may melt some ice sheets and sea levels will rise by 5-7 m in just decades. It will be true global catastrophe: entire countries (for example, Holland), Largest cities the world - New York, Tokyo, St. Petersburg, etc. - will be under water (IPCC, 2007).

The difference between our conclusions and the IPCC commission is only in assessing the scale of the geological factor in global warming. If the commission assigns the main role to technogenic human activity, then we believe that the role of natural processes is significantly higher. In our opinion, it is impossible to single out global climate changes as a separate independent channel in isolation from the general context of the geological development of the Earth.

True, this doesn’t make it any easier for people. Although, it is possible that the realization that it is not so much human civilization that is to blame for all this, but nature, somewhat reduces our sense of guilt before future generations.

- Are you saying that the end of the world is coming?

Of course not - this is not the end of the world, but this is one of the most difficult stages in the life of human civilization. During this period you should expect large number human casualties, worsening global economic crisis, destructuring of systems government controlled and international coordination of actions. But in certain regions it will be relatively calm and these territories can be identified in advance in order to prepare the appropriate infrastructure for them in advance.

You predict a difficult fate for entire generations, but do you and Academician Viktor Efimovich Khain have any proposals, if not for preventing, then at least for some reduction in the catastrophic consequences of impending cataclysms?

Of course there are and I will list them here:

· First of all, it is necessary to adopt the UN Framework Convention on Global Natural Disasters, following the example of the adoption in 1992 of the UN Framework Convention on Climate Change (UNFCCC), in response to the emergence of all more scientific evidence that global climate change is determined by anthropogenic changes in the content of greenhouse gases in the atmosphere.

· At the second stage, it is necessary to create a special International Intergovernmental Commission at the UN following the example of the Intergovernmental Commission on Climate Change (IPCC) with the inclusion of a special expert group that brings together leading world scientists in the fields of seismology, volcanology, geodynamics, climatology, meteorology, hydrology, etc.

· At the third stage, it is necessary, urgently, to develop and approve International Program UN to study and forecast the development of seismic and volcanic situations in conjunction with global climate change.

· The last and final stage of this process should be the creation of a single international financial fund and financial mechanism for preparing humanity for possible global natural disasters on a planetary scale. This stage will also include identifying the most stable and safe territories on our planet and creating special infrastructure on them to accommodate and support a large number of refugees, who will become the basis for the emergence of new centers of human civilization.

In conclusion, I would like to emphasize that only by combining our efforts, economic, technical and human resources, regardless of race, culture and religion, will human civilization be able to cross the great threshold that nature has prepared for it. It is this stage of her life that will give rise to the creation of a new formation of human society with a completely new positive thinking.

Thank you very much for such a detailed, scientifically sound and interesting interview. In conclusion, we would like to clarify where scientists and specialists can get acquainted with the results of your research?

Firstly, I want to inform you that recently, our joint monograph with Academician Viktor Efimovich Khain was published by the international publishing house SWB: Khain V.E., Khalilov E.N. Spatiotemporal patterns of seismic and volcanic activity. Bourgas, S.W.B., 2008. ISBN 978-9952-451-00-9

Considering the great interest in the problem, in agreement with the publishing house S WB, the book is posted for free use in the International Scientific Electronic Library of the World Organization for Scientific Cooperation - WOSCO Science Without Borders: www.wosco.org, as well as on the website: www.khalilov.biz

But some of the problems raised in the interview can be found right now in the articles:

V.E.Khain, E.N.Khalilov. ABOUT THE POSSIBLE INFLUENCE OF SOLAR ACTIVITY ON SEISMIC AND VOLCANIC ACTIVITY: LONG-TERM FORECAST

V.E.Khain, E.N.Khalilov. GLOBAL CLIMATE CHANGE AND CYCLICITY OF VOLCANIC ACTIVITY

Volcanoes differ in both appearance, and by the nature of the activity. Some volcanoes explode, spewing out ash and rocks, as well as water vapor and various gases. The eruption of Mount St. Helens in the United States in 1980 corresponded to this type of eruption. Other volcanoes can quietly pour out lava.

Why do some volcanoes explode? Imagine that you are shaking a bottle of warm soda water. The bottle may rupture, releasing water and carbon dioxide that is dissolved in the water. Gases and water vapor that are under pressure inside a volcano can also explode. The most powerful volcanic explosion ever recorded in human history was the eruption of Krakatoa Volcano, a volcanic island in the strait between Java and Sumatra. In 1883, the explosion was so strong that it was heard at a distance of 3,200 kilometers from the explosion site. Most of the island disappeared from the face of the Earth. Volcanic dust enveloped the entire Earth and remained in the air for two years after the explosion. The resulting giant sea wave killed more than 36,000 people on nearby islands.

Very often, before an eruption, volcanoes give a warning. This warning may be in the form of gases and steam released from the volcano. Local earthquakes may indicate that magma is rising within the volcano. The ground around the volcano or on the volcano itself swells and the rocks tilt at a large angle.

If a volcanic eruption occurred in the recent past, such a volcano is considered active or active. A dormant volcano is one that has erupted in the past but has been inactive for many years. An extinct volcano is one that is not expected to erupt. Most of the volcanoes on the Hawaiian Islands are considered extinct.

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1. Volcanic activity

2. Types of volcanic structures

3. Classification of volcanoes by shape

4. Volcanic eruption

5. Post-volcanic phenomena

6. Heat sources

7. Areas of volcanic activity

8. Volcanoes on other planets

9. Interesting facts

10. Eruptions

Literature

1. Volcanic activity

Volcanoes-- geological formations on the surface of the Earth's crust or the crust of another planet where magma comes to the surface, forming lava, volcanic gases, rocks (volcanic bombs) and pyroclastic flows.

The word "Vulcan" comes from the name of the ancient Roman god of fire, Vulcan.

The science that studies volcanoes is volcanology and geomorphology.

Volcanoes are classified by shape (shield, stratovolcanoes, cinder cones, domes), activity (active, dormant, extinct), location (terrestrial, underwater, subglacial), etc.

Volcanoes are divided depending on the degree of volcanic activity into active, dormant and extinct. An active volcano is considered to be a volcano that erupted during a historical period of time or in the Holocene. The concept of active is quite inaccurate, since a volcano with active fumaroles is classified by some scientists as active, and by others as extinct. Dormant volcanoes are considered to be inactive volcanoes where eruptions are possible, and extinct volcanoes are considered to be those where they are unlikely.

However, there is no consensus among volcanologists on how to define an active volcano. The period of volcanic activity can last from several months to several million years. Many volcanoes exhibited volcanic activity tens of thousands of years ago, but are not considered active today. Astrophysicists, from a historical perspective, believe that volcanic activity, caused, in turn, by the tidal influence of other celestial bodies, may contribute to the emergence of life. In particular, it was volcanoes that contributed to the formation of the earth’s atmosphere and hydrosphere, throwing out a significant amount carbon dioxide and water vapor, scientists also note that too active volcanism, such as on Jupiter’s moon Io, can make the surface of the planet unsuitable for life. At the same time, weak tectonic activity leads to the disappearance of carbon dioxide and sterilization of the planet. “These two cases represent potential boundaries for planetary habitability and exist alongside the traditional parameters of habitable zones for systems of low-mass main sequence stars,” the scientists write.

2. Types of volcanic structures

volcano activity shield cinder

In general, volcanoes are divided into linear and central, but this division is arbitrary, since most volcanoes are confined to linear tectonic faults (faults) in the earth’s crust.

Linear volcanoes or fissure-type volcanoes have extensive supply channels associated with a deep split in the crust. As a rule, basaltic liquid magma flows out of such cracks, which, spreading to the sides, forms large lava covers. Along the cracks, gentle spatter shafts, wide flat cones, and lava fields appear. If the magma has a more acidic composition (higher silicon dioxide content in the melt), linear extrusive ridges and massifs are formed. When explosive eruptions occur, explosive ditches can appear tens of kilometers long.

The shapes of central-type volcanoes depend on the composition and viscosity of the magma. Hot and easily mobile basaltic magmas create vast and flat shield volcanoes (Mauna Loa, Hawaiian Islands). If a volcano periodically erupts either lava or pyroclastic material, a cone-shaped layered structure, a stratovolcano, appears. The slopes of such a volcano are usually covered with deep radial ravines - barrancos. Volcanoes of the central type can be purely lava, or formed only by volcanic products - volcanic scoria, tuffs, etc. formations, or be mixed - stratovolcanoes. There are monogenic and polygenic volcanoes. The former arose as a result of a single eruption, the latter as a result of multiple eruptions. Viscous, acidic in composition, low-temperature magma, squeezed out of the vent, forms extrusive domes (Mont Pele needle, 1902). In addition to calderas, there are also large negative forms of relief associated with subsidence under the influence of the weight of erupted volcanic material and a pressure deficit at depth that arose during the unloading of the magma chamber. Such structures are called volcanotectonic depressions. Volcanotectonic depressions are very widespread and often accompany the formation of thick strata of ignimbrites - volcanic rocks of acidic composition, having different genesis. They are lava or formed by sintered or welded tuffs. They are characterized by lens-shaped segregations of volcanic glass, pumice, lava, called fiamme, and a tuff or tofo-like structure of the main mass. As a rule, large volumes of ignimbrites are associated with shallow magma chambers formed due to the melting and replacement of host rocks. Negative forms of relief associated with volcanoes of the central type are represented by calderas - large rounded failures, several kilometers in diameter.

3. Classification of volcanoes by shape

Shield volcanoes are formed as a result of repeated emissions of liquid lava (1). This shape is characteristic of volcanoes that erupt low-viscosity basaltic lava: it flows from both the central crater and the slopes of the volcano (2). Lava spreads evenly over many kilometers. Like, for example, on the Mauna Loa volcano in the Hawaiian Islands where it flows directly into the ocean.

Slag cones eject from their vent only such loose substances as stones and ash: the largest fragments accumulate in layers around the crater. Because of this, the volcano becomes higher with each eruption (1). Light particles fly away over a longer distance, which makes the slopes gentle (2).

Stratovolcanoes, or "layered volcanoes", periodically erupt lava and pyroclastic matter - a mixture of hot gas, ash and hot rocks. Therefore, deposits on their cone alternate (1). On the slopes of stratovolcanoes, ribbed corridors of solidified lava (2) are formed, which serve as support for the volcano.

Dome volcanoes are formed when granitic, viscous magma rises above the rim of a volcano's crater and only a small amount leaks out, flowing down the slopes (1). Magma clogs the volcano's crater, like a plug (2), which the gases accumulated under the dome literally knock out of the crater.

4. Eruption

Volcanic eruptions are classified as geological emergency situations, which can lead to natural disasters. The eruption process can last from several hours to many years. Among the various classifications, general types stand out:

Hawaiian type-- emissions of liquid basaltic lava, often formed lava lakes. should resemble scorching clouds or red-hot avalanches.

Hydroexplosive type-- eruptions that occur in shallow conditions of oceans and seas are characterized by the formation of a large amount of steam that occurs when hot magma and sea water come into contact.

5. Post-volcanic phenomena

After eruptions, when the activity of the volcano either stops forever, or it “dorms” for thousands of years, processes associated with the cooling of the magma chamber and called post-volcanic processes persist on the volcano itself and its surroundings. These include fumaroles, thermal baths, and geysers.

During eruptions, a volcanic structure sometimes collapses with the formation of a caldera - a large depression with a diameter of up to 16 km and a depth of up to 1000 m. As the magma rises, the external pressure weakens, associated gases and liquid products escape to the surface and a volcanic eruption occurs. If ancient rocks, and not magma, are brought to the surface, and the gases are dominated by water vapor formed when groundwater is heated, then such an eruption is called phreatic.

Rising to earth's surface lava does not always reach this surface. It only raises layers of sedimentary rocks and hardens in the form of a compact body (laccolith), forming a unique system of low mountains. In Germany, such systems include the Rhön and Eifel regions. In the latter, another post-volcanic phenomenon is observed in the form of lakes filling the craters of former volcanoes that failed to form a characteristic volcanic cone (the so-called maars).

6. Heat sources

One of the unresolved problems of volcanic activity is determining the heat source necessary for local melting of the basalt layer or mantle. Such melting must be highly localized, since the passage of seismic waves shows that the crust and upper mantle are usually in a solid state. Moreover, the thermal energy must be sufficient to melt huge volumes of solid material. For example, in the USA in the Columbia River basin (Washington and Oregon states) the volume of basalts is more than 820 thousand km?; the same large strata of basalts are found in Argentina (Patagonia), India (Deccan Plateau) and South Africa (Great Karoo Rise). Currently there are three hypotheses. Some geologists believe that the melting is caused by local high concentrations of radioactive elements, but such concentrations in nature seem unlikely; others suggest that tectonic disturbances in the form of shifts and faults are accompanied by the release of thermal energy. There is another point of view, according to which the upper mantle under conditions of high pressure is in a solid state, and when, due to fracturing, the pressure drops, it melts and liquid lava flows through the cracks.

7. Areas of volcanic activity

The main areas of volcanic activity are South America, Central America, Java, Melanesia, Japanese Islands, Kuril Islands, Kamchatka Peninsula, northwestern USA, Alaska, Hawaiian Islands, Aleutian Islands, Iceland, Atlantic Ocean.

8. Volcanoes on other planets

Volcanoes are found not only on Earth, but also on other planets and their satellites. Most high mountain The solar system is the Martian volcano Olympus, whose height is estimated at several tens of kilometers. IN solar system Jupiter's satellite Io has the greatest volcanic activity. The length of the plume of erupted material reaches 300 km. On some planetary satellites in conditions low temperatures It is not magma that erupts, but water and light substances. This type of eruption cannot be classified as ordinary volcanism, which is why this phenomenon is called cryovolcanism.

9. Interesting Facts

In 1963, the island of Surtsey emerged as a result of the eruption of an underwater volcano off the south of Iceland.

The eruption of Mount Krakatoa in Indonesia in 1883 produced the loudest roar ever heard in history. The sound was heard at a distance of more than 4,800 km from the volcano. Atmospheric shock waves circled the Earth seven times and were still visible for 5 days. The volcano killed more than 36,000 people, razed 165 villages and damaged another 132, mostly in the form of tsunamis that followed the eruption. Volcanic eruptions after 1927 created a new volcanic island called Anak Krakatoa ("Child of Krakatoa").

Kilauea Volcano, located in the Hawaiian archipelago, is the most active volcano at present. The volcano rises only 1.2 km above sea level, but its last prolonged eruption began in 1983 and is still ongoing. Lava flows extend 11-12 km into the ocean.

An active volcano has been discovered in Taipei, Taiwan. It was previously thought that the last volcanic activity in this area was more than 200,000 years ago, but it turned out that the last activity was only 5,000 years ago.

In 2010, the eruption of the Eyjafjallajokull volcano caused the cancellation of more than 60 thousand flights across Europe.

In 1908, in Antarctica, on Penguin Island, the village of Volcano Penguin top was founded on the top of an active volcano.

10. Eruptions

10.1. XXI Century

10.2. XX century

Literature

1. M. Yampolsky. Volcano in European culture of the 18th-19th centuries. // Yampolsky M. Observer. M., 2000, p. 95-110

2. Fundamentals of Geology, N.V. Koronovsky, A.F. Yakusheva. - M.: Higher School, 1991. - P. 225-232.

3. Obruchev V.A. Fundamentals of Geology. State publishing house of geological literature. M.-L. 1947

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