Liliya Timoschenko
PERFORMANCE
Subject research: « Why do volcanoes erupt?» .
Section: Naturally - scientific.
Job spent time with a child in a preparatory group for school.
Target research: to know, why do volcanoes erupt?
Tasks research:
1. Find out what it is volcano?
2. How it works volcano?
3. What types are there? volcanoes?
4. Create a working model volcano at home.
Hypothesis: volcano erupts because the mountain is angry.
Method research:
1. Collection of information: reading a children's encyclopedia, conversations, looking at illustrations with different volcanoes;
2. Watching videos about volcanic eruption;
3. Research activity - experiment;
4. Making a layout volcano;
5. Summing up;
6. Presentation
The main part of the speech.
1 slide. Volcano- this is a hole in the earth’s crust through which a fiery mixture of gases, steam, ash and molten rock is thrown onto the surface with enormous force (lava).
2 slide. Ash particles fall to the ground, covering it in a thick layer. Over millions of years, tall lava layers form volcanic mountains, which have the shape of a cone with a crater on top. There is a hole or crack at the top of the mountain (crater). Inside volcano passage channel, along which molten lava comes to the surface.
3 slide. At very high temperatures, rocks melt in the ground; under the influence of movement, magma rises to the surface. The closer to the surface, the more gases become, and the magma turns into lava.
4 slide. By its activity there are volcanoes: active, dormant, extinct.
5 slide. "Filling" volcano: baking soda, water, vinegar, dish soap, red paint.
6 slide. Vulcan in action:
Conclusion: the gas formed when vinegar reacts with soda raises "lava" up and happening « eruption» .
During research the hypothesis was confirmed only from the point of view of mythology.
General education high school No. 10 Balkhash
Section: Natural science (inanimate nature)
Subject:
"VOLCANOES"
student of 1st "B" class
Secondary school No. 10 of the city of Balkhash
Supervisor: Kuznetsova Elena Vladimirovna - teacher primary classes
Balkhash, 2014
Introduction………………………………………………………..
Main part.
2.1 Theoretical study………………………………….
2.2 Practical research…………………………………..
III. Conclusion …………………………………………………………….
List of used literature……………………………………..
Glossary
Eruption volcano- the process of ejection by a volcano earth's surface hot debris, ash, an outpouring of magma, which, pouring out to the surface, becomes lava.
Crater – Depression at the top of the volcano. Lava flows out of a crater during a volcanic eruption.
Volcanic ash- Small particles of solidified magma, rock fragments and mineral crystals released into the atmosphere during a volcanic eruption and falling to Earth to form sediment.
Tectonic plates – gradually moving parts of the earth's crust covering our planet.
Volcanic bombs - pieces of frozen or hardening lava ejected from a volcano during an eruption.
Magma chambers- large accumulations of magma tending to the surface of the earth's crust.
Introduction
Purpose of the study:
Find out why volcanoes erupt.
Explore the structure of volcanoes.
Expand knowledge about volcanoes.
Research objectives:
Study additional literature and select interesting information, about what it is - a volcano;
Find out how a volcano works;
Find out what volcanoes are;
Create a working model of a volcano at home;
Learn experimentally about the properties of stones of volcanic origin;
Object of study: volcanoes
Subject: volcano
Hypothesis: the volcano erupts because the mountain is angry
Methods:
Analysis of scientific literature.
Conducting experiments.
Observation.
Main part
2. Theoretical research
A volcano is a naturally occurring hole in the earth's crust through which hot molten rock called lava, as well as gases, steam and ash (what remains after a solid substance has completely burned) burst out, often in large and noisy eruptions or explosions. These eruptions are thought to act as safety valves, releasing enormous amounts of heat and pressure deep within the earth. Typically, a volcano is a cone-shaped mountain (the walls of which consist of solidified lava and ash) with a hole in the center, or a crater, through which eruptions occur.
There are several various types, or stages of eruption. Many eruptions cause no noticeable damage environment. But there are very powerful and destructive eruptions. During such eruptions, lava can spill out and flow down from the volcano, flooding the surrounding areas; choking clouds of steam, ash, hot gases and stones can fall down, which descend to the ground at high speed, covering it for many kilometers around. (When Mount St. Helens on Mount Washington erupted in 1980, for example, it killed millions of trees.)
One of the most famous and destructive was the eruption of Mount Vesuvius (located in today's Italy) in 79 AD. As a result, the large Roman city of Pompeii was destroyed. A huge cloud of ash and ash covered the city, thanks to which it has been well preserved to this day. By studying these amazing ruins, scientists have learned a lot about the times Ancient Rome. Vesuvius is still an active volcano; this means that it experiences volcanic activity and erupts from time to time. There are also volcanoes that are described as dormant, meaning that they have not seen activity for a long time, but the conditions for a possible future eruption still exist. An extinct volcano is one that will never erupt again.
Volcanoes often occur in places where there are tectonic plates or ridges in the earth's crust. Around Pacific Ocean– where the plates of the earth’s crust meet, there is a whole group of volcanoes, which are known as the “ring of fire”. Due to the movement of tectonic plates in these areas, liquid rock (called magma) trapped in voids within the Earth can rise, causing volcanic activity. (This also often causes earthquakes.) Volcanic activity can occur both on land and in the oceans. As a result, islands sometimes form in the oceans. This is how the Hawaiian Islands appeared about 40 million years ago. And even today, two of the most active volcanoes - Mauna Loa and Kilaua - are located on an island in Hawaii. Tourists visiting National Park Hawaiian volcanoes can hike the slopes surrounding the great volcanoes.
There are mountain volcanoes, and there are also underwater volcanoes that are completely hidden under water. “Waking up,” such volcanoes erupt not only magma, but also entire fountains of water.
There are mud volcanoes, which erupt streams of hot mud, and lake volcanoes. The craters of such volcanoes look like a flat plate filled with boiling lava.
But why do volcanoes still erupt? In the depths of the earth's crust, rocks melt at very high temperatures - magma is formed. Under the influence of the movement of tectonic plates, magma rises to the surface of the earth and accumulates in the volcanic chamber under the volcano. The gases that make up the magma tend to exit to the surface - to the crater, and raise the magma with them. The closer to the crater, the more gases become, the magma changes its composition and turns into lava. Volcanic eruptions begin with the release of gases and volcanic ash. Explosions can also occur, then volcanic bombs - pieces of solidified lava - fly into the air from the vent, and then the molten lava flows down the slope. After a violent eruption process, the pressure in the magma chamber decreases and the volcanic eruption stops.
Famous volcanoes.
An active volcano in southern Italy, about 15 km from Naples. Height - 1281 meters. The crater is about 750 m in diameter. One of three active volcanoes in Italy, the only active volcano in continental Europe. It is considered one of the most dangerous volcanoes in the world.
The last historical eruption of Mount Vesuvius occurred in 1944. One of the lava flows destroyed the cities of San Sebastiano and Massa. 57 people died during the eruption. The height of the lava fountain from the central crater reached 800 m.
Fujiyama.
Vulcan on Japanese island Honshu is 150 kilometers west of Tokyo. The height of the mountain is 3776 m (the highest in Japan). The volcano is weakly active; its last eruption was in 1707.
Krakatoa.
Krakatoa is a former island and active volcano in Indonesia, located in the Sunda Strait, between the islands of Java and Sumatra.
The study of the volcano and surrounding areas has established traces of powerful prehistoric eruptions. According to volcanologists, one of the most powerful eruptions occurred in 535. This eruption led to global climatic consequences on Earth, as noted by scientists who studied the annual rings of ancient trees in different areas of the planet.
2.2 Case studies
To see in practice how volcanic eruptions occur, I conducted several experiments.
Experiment No. 1 “Movement of magma in the depths of the earth’s crust.” I immersed slabs of chocolate that stood in for tectonic plates in colored dough called “magma.” Using sticks, he created movement and saw that “magma” was seeping into the cracks. Conclusion: Under the influence of the movement of tectonic plates, magma can rise to the surface of the earth.
Experiment No. 2 “Creating a model of an active volcano at home.” I made a cone out of cardboard. I covered it with plasticine and gave it the color of a volcano. Placed a bottle inside the cone. I filled the bottle with “lava” - a mixture of baking soda, liquid soap and red gouache paint. I filled the “volcano” with vinegar and it erupted. Conclusion: the gas formed when vinegar reacts with water lifts the “lava” upward and an eruption occurs.
Experiment No. 3 “Properties of stones of volcanic origin.” I immersed stones of various rocks in water. Observing the process, I found out that all the stones were sinking, except for pumice, a stone of volcanic origin. Conclusion: Pumice has a porous structure. The pores are filled with air, so the stone does not sink (pores in pumice are formed when the lava hardens, when gases are still escaping).
Conclusion
During the study, the hypothesis was not confirmed. The ancient Romans also believed that God was angry, which is why the eruption occurs - a manifestation of God's anger. In fact, the volcano erupts because magma has accumulated in the volcanic chamber and, under the influence of the gas included in its composition, it rises to the top. In the crater of a volcano, the amount of gas becomes greater. The magma turns to lava, reaches the crater and erupts.
Volcanoes are a formidable natural phenomenon. Volcanic eruptions threaten human life and cause damage to the entire environment, so we need to know about them, like any natural phenomenon of which we are a part.
List of used literature
Internet resources
http://www.bugaga.ru/interesting/1146713964
Internet resources
http://zemlyanin.info/samye-izvestnye-vulkany-zemli/
Internet resources
http://ru.wikipedia.org
Internet resources
http://www.vseneprostotak.ru/jenciklopedija/vulkany/
Municipal budgetary educational institution
Lyceum No. 4
Why do volcanoes erupt?
Krivosheev Timur Vladimirovich
3rd grade student
Supervisor:
Krivosheeva Natalya Evgenievna
primary school teacher
Dankov
2015
Table of contents
1.Introduction………………………………………………………………………………….……...2
Goals and objectives research work…………………………………….…2
2. Main part.
2.1 Questioning classmates………………….….….. 3
2.2 Experience No. 1. Movement of magma from the bowels of the earth……………………………5
2.3. Experience No. 2.How does a volcano erupt?…………………..…6
2.4 Experience No. 3.Properties of volcanic stones ………...7
2.5 Consequences of volcanic eruptions…………………….8
3. Conclusions………………………………………………………………………………….…...… 8
4. Conclusion………………………………………………………………………………...8
5. Bibliography……………….…………………………...........9
The year before last, I heard on the news about a volcanic eruption in Russia. The Klyuchevskaya Sopka volcano began to erupt in Kamchatka. I was interested in how and why this volcano woke up. These questions helped me decide on the topic of my research work. I decided to find out why volcanoes erupt.
Goal of the work - summarize and classify information about volcanoes.Find out the reasons why volcanoes erupt.
Tasks:
Find out what a volcano is?
Study the structure of a volcano.
Find out what kinds of volcanoes there are?
Conduct an experiment and find out how and why a volcano erupts.
Find out what consequences volcanic eruptions have.
Create a working model of a volcano at home.
Learn experimentally about the properties of stones of volcanic origin.
Research methods:
Conversations with adults.
Questioning classmates.
Study and analysis of various sources of information.
Conducting experiments.
Observations.
Hypothesis:
volcanoes erupt because there is a lot of liquid magma under the earth's crust, and therefore it comes out.
Questioning classmates
I began my search for reasons explaining why volcanoes erupt by conducting a survey among my classmates.
To the question “Why do volcanoes erupt?” The guys gave the most votes to the answer “from an earthquake.” They also believe that the sun and geographic location have a special influence on volcanic eruptions.
What is a volcano
From the Internet I learned that the word “Vulcan” comes from the name of the island of Vulcano off the coast of Italy, where, according to legend, one of the forges of the ancient Roman god of fire Vulcan (Hephaestus) was located.
I read in the encyclopedia that a volcano is a geological formation that appears above channels and cracks in the earth's crust, through which lava, volcanic gases and stones erupt onto the earth's surface.
Types of volcanoes:
Active - These are volcanoes that erupt regularly.
Extinct - These are volcanoes whose activity has ceased and they no longer erupt.
Asleep - these are volcanoes that were considered extinct, but suddenly began to act.
A volcano consists of: MAGMA OR LAVA - molten rocks saturated with gases. VENT - a channel through which magma rises to the crater. Crater - a bowl-shaped depression at the top of a volcano.
To find out where magma comes from, I first studied the structure of our planet. I learned that the Earth resembles an egg: on top there is a thin hard shell - the earth's crust, underneath there is a viscous layer of hot mantle, and in the center there is a solid core.
Inside the Earth, due to temperature differences, there is a constant movement of the mantle. Pieces of the earth's crust (tectonic plates) also move along with it.When plates collide, one plate goes down and begins to melt - turns into magma. Magma rises to the surface and accumulates in magma chambers.
Experience No. 1. Movement of magma from the depths of the earth
I decided to experimentally see what happens to magma when tectonic plates collide. To do this, I conducted my first experiment, “Movement of magma from the bowels of the Earth.” To do this, I immersed solid chocolate bars, which replaced tectonic plates, in “magma” yoghurt. Using sticks, I began to move my “tectonic plates.” The “plates” began to collide with each other, some plates went under others, and at this point the “magma” was pushed to the surface of the “plates”.
Conclusion:
The experience helped to understand how, under the influence of the movement of tectonic plates, magma moves to the surface of the earth.
Magma rises to the surface and accumulates in magma chambers. There it is under pressure, just like carbonated drinks in a closed bottle.
The gases that make up the magma tend to go out and lift the magma along the crater of the volcano. These gases are flammable, so they ignite and explode in the crater of a volcano. Gases, ash, hot rocks and magma burst out through the crater of the volcano.
Experience No. 2. How does a volcano erupt?
My second experience helped me figure out why magma starts to erupt from a volcano. I made a cone out of paper and gave it the color of a volcano. Place a glass inside the cone. I filled the glass with “lava” – a mixture of baking soda, liquid soap and red paint. Filled a volcano with vinegar and caused an eruption.
Conclusion:
The gas formed when vinegar reacts with soda raises the “lava” upward and an “eruption” occurs.
Experience No. 3. Properties of volcanic stones
For a long time I was passionate about collecting the collection of stones “Minerals. Treasures of the Earth." From it I learned that stones of volcanic origin were formed as a result of volcanic eruptions and the cooling of volcanic magma. They are characterized by durability, high density and good hardness. But there is one stone that is formed when magma releases a lot of gases, it foams and cools. This is pumice.
This stone has a porous structure. The pores are filled with air. Therefore, pumice does not sink. I decided to test this experimentally. I took stones of volcanic origin from the collection: granite, obsidian, gneiss, galena, basalt, andesite and pumice. Immersed them in water. All the stones sank, but the pumice remained on the surface of the water.
Conclusion:
Pumice is a rock of volcanic origin that does not sink in water.
Consequences of volcanic eruptions
Volcanic eruptions have a strong Negative influence, bring colossal destruction and death.
But these fire-breathing mountains also give man hot water, energy, various rocks, metals and even gems. Volcanic ash increases soil fertility, so volcanoes bring not only destruction, but also benefit.
conclusions
1. While working on this project, I plunged into the world of fascinating experiences, became acquainted with the structure of a volcano and the process of its eruption, and learned that volcanoes bring not only harm, but also benefit.
2. My hypothesis that a volcanic eruption occurs because there is too much magma was partially confirmed. As a result of my research and experiments, I concluded that a volcanic eruption occurs because magma is lifted to the surface of the Earth by the gases contained in it.
Conclusion
I found the answer to my question "Why do volcanoes erupt". I would like morestudy the giant volcanoes in more detail and find out whether it is possible to predict and eliminate the consequences of the eruptions of these giants.
I also want to present my work to my classmates and hope to get them interested in my research.
http://www.stranamam.ru/post/5375998/ 2. “Volcanoes” Aprodov V.A.3. “Volcanoes” by Christina Godin, Children's Encyclopedia Machaon
4. Encyclopedia. “Minerals. Treasures of the earth."
5. Great Russian Encyclopedia / Ch. ed. Yu. S. Osipov. - M.: Scientific. publishing house "BRE", 2004.
Department of Education of the Asbestovsky Urban District
"Secondary school No. 30"
Research project
“Why do volcanoes erupt?”
Supervisor:
___________O.P. Kulichkova
"____"______________2015
Completed:
students of 3 "A" class
N.A.Kopin,
B.R. Koch
10.02.2015
2015
Department of Education of the Asbestovsky Urban District
Municipal autonomous educational institution
"Secondary school No. 30"
Asbestovsky urban district
Research project
Is a volcano a dangerous natural phenomenon?
Scientific and technical direction
Section: man and environment
Kopin Nikita Andreevich,
Kokh Bogdan Ruslanovich,
students of 3 "A" class
Supervisor:
Kulichkova Olga Pavlovna,
primary school teacher.
2015
CONTENT
INTRODUCTION
Each of us has heard a lot about volcanoes, some were even lucky enough to visit one of them, but most people have a very superficial understanding of what a volcano is, what its nature is, how they arise and why they erupt.
In the Tyrrhenian Sea, in the group of Aeolian Islands, there is a small island of Vulcano. Since time immemorial, people have observed how fire and clouds of black smoke sometimes burst out from the top of a huge mountain on the island and hot stones were thrown to great heights.
The ancient Romans considered this island the entrance to hell, as well as the domain of the god of fire and blacksmithing, Vulcan. After the name of this god, the fire-breathing mountains were later called volcanoes.
Our project is devoted to the questions of how volcanoes appear, what they are like, and what a person should do if a volcano erupts nearby.
Why is the topic interesting?
Object: Volcano – a natural phenomenon
Subject: Volcanic eruption
Purpose of the research project:
Find out whether the volcano poses a danger to human life and health.
When performing this work, the following tasks were set:tasks:
find out what a volcano is;
find out how and where volcanoes form;
clarify what exactly happens during a volcanic eruption;
find out whether volcanoes erupt in the Urals;
develop a memo on the behavior of a person caught in a volcanic eruption zone;
conduct the “Boiling of Water” experiment
conduct the experiment “Degassation” mineral water»
conduct practical work “Volcanic eruption at home”;
develop the ability to competently present material on a topic based on its analysis;
improve the culture of oral speech;
develop the skill of using a computer in educational activities.
Methodsresearch: study and analysis of literature, Internet sources on the project topic, generalization, conclusion, experience and observation, questioning, practical work.
Work plan
passport
Hypotheses :
Let's assume that scientists can predict the time of a volcanic eruption.
Structure of the Earth
Rationale
We see what is on the surface of the Earth. But if we dig a hole to the center of the Earth, what will we see there? Nobody knows for sure. Scientists are trying to find out by studying different layers of the earth.
It is very difficult for man to penetrate deep into the Earth. The world's deepest well was drilled on the Kola Peninsula to a depth of 12 kilometers. And the radius of the Earth, i.e. the distance from the surface to its center is over 6000 kilometers. Therefore, the interior of our planet, located at great depths, is studied based on the results of seismic exploration. Every hour on various points The earth registers about 10 vibrations of the earth's surface. Thousands of seismic stations study the propagation of waves during an earthquake. These waves diverge in the thickness of the Earth in the same way as ripples on water from a thrown stone. When a wave hits a denser layer, its speed changes dramatically. Using this data, scientists determined the boundaries of the inner shells of the Earth.
The upper shell of the Earth is the earth's crust. The thickness of the earth's crust varies from 5 km in oceanic areas to 70 km in mountainous areas of the continents. The earth's crust gives way to the mantle, its thickness is almost 3000 km. The mantle, which receives heat from the core, is heated from 800° at the top to 2000° at the core. It is believed that the substance of the mantle is in continuous motion. At the center of the Earth is the core. It consists mainly of iron and nickel. And it is divided into two layers: a solid inner core and a liquid outer core. The core temperature reaches 6000°. Due to the enormous pressure in the center of the Earth, the density of matter in the earth's core is very high. One cubic meter of this substance weighs about 12.5 tons, the same as three adult elephants weigh.
Giant parts of the earth's crust move along the surface of the soft mantle. These moving pieces of crust are called tectonic plates. When these huge plates collide with each other, earthquakes occur, volcanoes erupt and mountains slowly form.
In fact,volcano - This is a hole in the earth's crust.When a volcano erupts from the depths of the Earth to the surface, very hot molten rocks erupt through this hole.
Conclusionanalysis of sources showed that
Why do volcanoes erupt?
Hypothesis No. 1. Perhaps the volcano erupts because the lava gradually heats up, like water in a kettle, and then “boils away.”Photo teapot and volcano
In Chapter One, we learned that the temperature of the mantle is thousands of degrees. Closer to the core, the temperature of the mantle is higher; the further from the core, the lower the temperature. Due to the temperature difference, the mantle substance is mixed: hot masses rise upward, and cold masses descend (just like boiling water in a pan or kettle, but this only happens thousands of times slower).
Experience 1. Boiling water
Equipment : saucepan, gas stove.
Progress of the experiment .
The experiment is performed in the presence of the mother of one of the authors. When heated, the water gradually rises up
Conclusion . Having compared the results of the experiment with photographs of an erupting volcano, we noticed that the water, having passed into a gaseous state, rises upward in the form of steam. Which is very similar to a column of matter rising above a volcano.
The mantle, although heated to enormous temperatures, is due to the colossal pressure in the center of the Earth not liquid, but viscous, like very thick tar. The lithosphere (the earth's crust) seems to float in a viscous mantle, submerging slightly into it under the weight of its weight.
Reaching the base of the lithosphere, the cooling mass of the mantle moves horizontally for some time along the solid crust, but then, having cooled, it descends again towards the center of the Earth. While the mantle moves along the lithosphere, pieces of the earth's crust (lithospheric plates) inevitably move along with it, while individual parts of the stone mosaic collide and creep onto each other.
The part of the plate that was below (on which another plate crawled) gradually sinks into the mantle and begins to melt. This is how it is formedmagma - a thick mass of molten rocks with gases and water vapor. Magma is lighter than the surrounding rocks, so it slowly rises to the surface and accumulates in the so-calledmagma chambers . They are most often located along the plate collision line.
Magma is more fluid than the mantle, but still quite thick. Translated from Greek, “magma” means “thick paste” or “dough.”
The behavior of hot magma in a magma chamber really resembles yeast dough: magma increases in volume, occupies everything free space and rises from the depths of the Earth along cracks, trying to break free. Just as dough lifts the lid of a pan and flows over the edge, so magma breaks through the earth's crust in the deepest weak points and bursts to the surface. That's what it iseruption
.
A volcanic eruption occurs due todegassing of magma , that is, the release of gases from it. Everyone knows the degassing process: if you carefully open a bottle of a carbonated drink (lemonade, Coca-Cola, kvass or champagne), a pop is heard, and smoke appears from the bottle, and sometimes foam - this is gas coming out of the drink (that is, it is degassing) .
Experience 2 . Degassing of mineral water.
Equipment : bottleWhichheated mineral water, 1.5 liters
Progress of the experiment : The experiment is performed in the presence of the mother of one of the authors.bought, heated, shook, another takes pictures
Conclusion: if the bottle is shaken or heated before opening, a powerful jet will burst out of it, and this process can be maintainedimpossible, just like during a volcanic eruption.photo
The magma in a magma chamber is under pressure, just like a carbonated drink in a closed bottle. In the place where the earth’s crust was “loosely closed,” magma can escape from the bowels of the Earth, knocking out the “plug” of the volcano, and the stronger the “plug” was, the stronger the volcanic eruption will be. Rising upward, magma loses gases and water vapor and turns intolava – magma depleted in gases.
Unlike fizzy drinks, the gases released during a volcanic eruption are flammable, so they ignite and explode in the crater of the volcano. The force of a volcano explosion can be so powerful that a huge “funnel” remains in the place of the mountain after the eruption (caldera ), and if the eruption continues, then a new volcano begins to grow right in this depression.
However, it happens that magma manages to find an easy way out to the surface of the Earth, then lava flows out of volcanoes without any explosions at all. So the boiling porridge, gurgling, overflows over the edge of the pan. This type of eruption occurs, for example, in the Hawaiian Islands. Magma does not always have enough strength to reach the surface, and then it slowly solidifies at depth. In this case, a volcano does not form at all.
Conclusion : the hypothesis is proven. A volcano erupts because hot gases rise to the top and carry magma with it.
The structure of volcanoes, types of volcanoes
Hypothesis 2. What if a volcanic eruption could be stopped?
To prove the hypothesis, consider the structure of the volcano.
Volcanoes are usually cone-shaped with slopes that are gentle at their bases and steeper at their summits. If you climb to the topcurrent volcano, when it is calm, you can see the crater - deep depression with steep walls, like a giant bowl. The bottom of the crater is covered with fragments of large and small stones, and jets of gas and steam rise from the cracks. Some jets rise calmly, others burst out with hissing and whistling. The crater is filled with choking gases, forming a cloud at the top of the volcano. So the volcano can quietly smoke for months and years until an eruption occurs.
How does a volcano work anyway?
Hypothesis No. 2. What if a volcanic eruption could be stopped?
When a “valve” in the Earth opens (the plug of a volcano is knocked out), the pressure in the upper part of the magma chamber decreases sharply. Below, where the pressure is still high, dissolved gases are still part of the magma. In the crater of the volcano, gas bubbles are already beginning to be released from the magma: the higher you go, the more of them there are; these light “balloons” rise upward and carry the viscous magma with them. A continuous foamy mass has already formed near the surface (frozen volcanic stone foam is even lighter than water - this is known to everyonepumice ). Degassing of magma is completed at the surface, where, having broken free, it turns intolava , ash , hot gases , water vapor Androck fragments .
After a rapid degassing process, the pressure in the magma chamber decreases and the volcanic eruption stops. The volcano’s mouth is closed with solidified lava, but sometimes not very firmly: enough heat remains in the magma chamber, so volcanic gases can escape to the surface through cracks (fumaroles ) or jets of boiling water (geysers ). In this casethe volcano is still considered active . At any moment, a large amount of magma can accumulate in the magma chamber, and then the eruption process will begin again.
There are known cases when volcanoes erupted and remained silent for 300, 500, and 800 years. Volcanoes that have erupted at least once in human memory (and can erupt again) are calledsleeping .
Extinct (or ancient)volcanoes - these are those that worked in the distant geological past. For example, the capital of Scotland, the city of Edinburgh, stands on an ancient volcano that erupted more than 300 million years ago (there were no dinosaurs then).
Volcanic danger
The nature of the danger depends on the action of various factors. Lava flows destroy buildings, block roads and agricultural lands, which are excluded from economic use for many centuries until new soil is formed as a result of weathering processes. For example, on the wetter slopes of Mount Etna in Italy, agriculture on lava flows resumed only 300 years after the eruption.
As a result of volcanic eruptions, thick layers of ash accumulate on the roofs of buildings, which threatens their collapse.
The entry of tiny ash particles into the lungs leads to the death of livestock. Ash suspended in the air poses a danger to vehicles and air transport. Airports are often closed during ashfalls. Ash flows, which are a hot mixture of suspended dispersed material and volcanic gases, move at high speed. As a result, people, animals, plants die from burns and suffocation and houses are destroyed. The ancient Roman cities of Pompeii and Herculaneum were affected by such flows and were covered with ash during the eruption of Mount Vesuvius. Volcanic gases released by volcanoes of any type rise into the atmosphere and usually cause no harm, but some of them may return to the earth's surface in the form of acid rain. Sometimes the terrain allows volcanic gases (sulfur dioxide, hydrogen chloride or carbon dioxide) to spread near the surface of the earth, destroying vegetation or polluting the air in concentrations exceeding permissible limits. Volcanic gases can also cause indirect harm. Thus, the fluorine compounds contained in them are captured by ash particles, and when the latter fall onto the earth's surface, they contaminate pastures and water bodies, causing severe diseases in livestock. In the same way, open sources of water supply to the population can be contaminated.
Mud-stone flows (mudflows) and tsunamis also cause enormous destruction.
Volcanoes in the Urals
Hypothesis No. 3. We think that there are volcanoes in the Urals.
Are there active volcanoes in the Urals?There cannot be volcanoes in the Urals.The Ural Mountains are a region of ancient mountains. And volcanoes are seismic activity observed in youngfoldedareas, namely in the areasCenozoicera. Kamchatka, the Kuril Islands - this is where there are a lot of volcanoes. The Urals were formed over 200 million years ago and their growth stopped long ago. The age of the mountains should be 10 times less, and they should still be forming to this day, then there may be volcanoes, which we cannot say about the Ural Mountains.
But it should be noted that there are extinct volcanoes in the Urals. For example: Lake Talkaz, on the Irendyk ridge in Bashkortostan, is located in the crater of an extinct volcano. And the resort of Yangantau (translated from Bashkir as “burning mountain”) is located next to an extinct volcano; in some places it is still “smoking”, i.e. some kind of volcanic processes are taking place. Even if these volcanoes erupted, it was a very long time ago. Consider, for example, Yangantau foreverextinguished, would be wrong - with the slightest earthquake there is a possibility that such volcanoes could “wake up!”
Conclusion: The hypothesis has been partially proven. In the Urals there are only extinct volcanoes.
Eruption forecast.
Map with volcanoes
To forecast eruptions, volcanic hazard maps are compiled showing the nature and areas of distribution of products of past eruptions, and eruption precursors are monitored. Such precursors include the frequency of weak volcanic earthquakes; If usually their number does not exceed 10 in one day, then immediately before the eruption it increases to several hundred. Instrumental observations of the most minor surface deformations are carried out. Data on changes in height, distance and slope are used to identify the center of heave preceding an eruption or surface subsidence after an eruption. Before an eruption, the temperatures of the fumaroles increase, and sometimes the composition of volcanic gases and the intensity of their release change. The precursor phenomena that preceded most eruptions are similar. However, it is very difficult to predict with certainty exactly when an eruption will occur.
Volcanological observatories . To prevent a possible eruption, systematic observations are carried out in special observatories. The oldest volcanological observatory was founded in 1841-1845 on Vesuvius in Italy, then in 1912 the observatory on the Kilauea volcano on the island of Hawaii began operating, and at about the same time several observatories in Japan began operating. Volcano observations are also carried out in the USA (including at Mount St. Helens), Indonesia at the observatory at the Merapi volcano on the island of Java, in Iceland, Russia by the Institute of Volcanology of the Russian Academy of Sciences (Kamchatka), Rabaul (Papua New Guinea), on the islands of Guadeloupe and Martinique in the West Indies, and monitoring programs have been launched in Costa Rica and Colombia.
Notification methods . Civil authorities, to whom volcanologists provide the necessary information, must warn about impending volcanic danger and take measures to reduce the consequences. The public warning system can be sound (sirens) or light (for example, on the highway at the foot of the Sakurajima volcano in Japan, flashing warning lights warn motorists about ash fall). Warning devices are also installed that are triggered by elevated concentrations of dangerous volcanic gases, such as hydrogen sulfide. Roadblocks are placed on roads in hazardous areas where an eruption is taking place.
Reducing the hazards associated with volcanic eruptions . To mitigate volcanic hazards, both complex engineering structures and completely simple ways. For example, during the eruption of the Miyakejima volcano in Japan in 1985, cooling of the lava flow front with sea water was successfully used. By creating artificial gaps in the hardened lava that limited the flows on the slopes of volcanoes, it was possible to change their direction. For protection against mud-stone flows -lahars – use protective embankments and dams that direct flows into a certain channel. To avoid the occurrence of lahar, the crater lake is sometimes drained using a tunnel (Kelud volcano on Java in Indonesia). In some areas, special systems are being installed to monitor thunderclouds, which could bring downpours and activate lahars. In places where eruption products fall out, various shelters and safe shelters are built.
Lahars
Lahars are mudflows of volcanic origin. As a result of lava ejection or pyroclastic flows, snow cover and glaciers on the slopes of the volcano rapidly melt, and the resulting water mixes with ash and rocks. During the eruption of Vesuvius in 79, under the ashes of which Pompeii was buried, the city of Herculaneum was covered with a three-meter layer of mud-stone mass brought by the lahar. During excavations, it was discovered that the mudflow shell of Herculaneum is much denser than the ash layer of Pompeii.
The largest volcanic eruptions
We invite you to familiarize yourself with the largest and most powerful volcanic eruptions that occurred on our planet Earth.
Chronological table of the most powerful volcanic eruptions
1470 BC
Greece,
1226 BC
Italy,
1170 BC
Italy, Etna
1149 BC
Italy, Etna
525 BC
Italy, Etna
1902
May 8 - Martinique, ;
May 7 and 8 - West Indies, ;
October 24 - Guatemala,
1169
Italy,
1909
Indonesia, Kelud
1549
Guatemala, Aqua
1919
Indonesia,
1741
Ecuador, Cotopaxi
1772
Indonesia,
1793
Indonesia,
February 1793 - July 1794 - Italy,
April 1 - Japan,
1794
Ecuador, Tunguragua
Rules of behavior during a volcanic eruption, tips, recommendations
Having found out that volcanoes are dangerous and realizing that it is possible to survive a volcanic eruption, we decided to learn the rules of conduct during a volcanic eruption.
As well aseruption often happens unexpectedly and a person has no choice but to quickly respond to this incident. The danger posed by an active volcano increases the closer you are to the smoking mountain.
Most powerful eruptions are accompanied by eruptions, which seem to warn all living things around that danger is very likely in the near future. It is in this situation that emergency services alert the public about a potential volcanic eruption.
So, what are theybasic rules of behavior during a volcanic eruption?
1. If you live in close proximity to a volcano, constantly monitor reports about its condition, prepare a backpack with the most necessary things and documents. He must always be ready.
2. If you receive a warning about an eruption or possible subsequent complications (,), preserve your home, collect all the most necessary things and look for shelter, preferably away from fire-breathing, ash-spewing, lava-oozing slopes until better times, until the danger passesvolcanic eruption.
3. If you did not have time to leave and the eruption took you by surprise, be sure to protect your body and head from ash and stones. Almost everything will protect your head from wooden structures to the cardboard, a respirator will take care of your breathing. Well, if you are 100% prepared, then you can take out your gas mask.
4. Volcanic eruptions are often accompanied by mudflows and flooding. Therefore, avoid river valleys, especially near a volcano, try to climb as high as possible so as not to become a victim of water flows or mudflows.
5. If atvolcanic eruptionIf you are leaving the danger zone by transport, choose a route opposite to the direction of the wind. This will help you avoid an unpleasant encounter with ashes in the future.
6. The average speed of lava movement is 40 km/h. It’s quite possible to leave her. As in the case of ash, it is worth choosing a direction of movement perpendicular to the flow.
7. Wear as many warm clothes as possible. This will protect your body from acid, which will be formed in huge quantities as a result of reaction with the environment.
8. After the eruption, do not rush to return to your home. The signal should be messages from emergency services. If possible, spend a few days away from the area affected by the volcano.
9. Upon returning to your home, try not to open the windows for as long as possible (2-3 weeks) until the ash has completely disappeared from the environment. Remember to protect your respiratory organs.
The above describes simple, basicrules of conduct during a volcanic eruption. In each individual case, you should make informed decisions without panic. Vanity will only aggravate the situation, and in this case it will be much more difficult to survive.
It is worth noting that the danger from a volcanic eruption exists not only for the region around the mountain. Potentially, volcanoes threaten the lives of all life on Earth, so you shouldn’t be lenient towards these “hot guys.”
Practical work “Volcanic eruption at home”
Target: create a model and observe the process illustrating a volcanic eruption
Equipment:
Place of work: chemistry laboratories
Supervisor:
While working on the project, we learned about chemical experiment, which looks like a volcanic eruption.
This experiment was first carried out by Rudolf Böttger in the mid-19th century. Scientist discovered the substance ammonium dichromate, crystalline powder orange color. In the process of studying the properties of this substance, he conducted the following experiment. Having poured a pile of crystals onto a plate, Boettger brought a burning splinter to it. The crystals did not flare up, but something began to boil around the end of the burning splinter, and hot particles began to rapidly fly out. The hill began to grow and soon took on impressive dimensions.(Fig. 38).Its color also changed: instead of orange it became green.
Later it was found that ammonium dichromate spontaneously decomposes not only from a lit splinter or match, but also from a heated glass rod. This releases nitrogen gas, water vapor, and solid particles of hot chromium oxide Cr 2 0 3 and a lot of warmth.
We decided to conduct such an experiment. To do this, we bought ammonium dichromate and turned to our chemistry teacher for advice.
Under the guidance of a teacher, we poured 1 teaspoon of ammonium dichromate onto a special fire-resistant surface; on gas burner Heated one end of the glass tube and placed the heated end of the tube against the center of the slide. A few seconds later, sparks began to fly out from under the tube, and the volcano began to “erupt.” Sparks flew, ashes covered the table around, the small slide became three times larger, and a “crater” formed.
This experience allowed us to clearly see the formation of a volcano and imagine how the eruption process itself proceeds.
CONCLUSION
APPLICATIONS
Appendix A
Probably the most famous disaster in human history is the one that occurred in 79 in Italy. It cannot be said that the eruptionVesuvius was the most powerful volcanic eruption ever to occur on our planet. Not at all. But it happened in the center of a powerful country, in front of the eyes of people who were confident in the exclusivity of their country, a large prosperous city was destroyed. The shock of this disaster can be compared to the effect that the destruction of the Twin Towers in New York had in 1922.
Pompeii and Vesuvius
Pompeii was one of the most developed centers of the Roman Empire. There was everything that characterized a large metropolis of the Roman era - temples, baths, theaters. Prominent representatives of science and culture also worked here. But here was also the future killer of the city - the famous volcanoVesuvius.
HeightVesuvius above sea level - about 1300 m. Scientists believe that back in the 9th century. BC. it was twice as high, but a powerful eruption destroyed most of it. Since then, the volcano has erupted more than eighty times. However, as usually happens, people quickly forgot about the disaster. But in the vicinity and on the slopes of the volcano there was very fertile soil, which attracted settlers here. Along the coast there were numerous fishing villages; rich Romans built their villas here.
In 62 AD e. strong tremors shook the cities aroundVesuvius, partially destroyingPompeii, Herculaneum , Stabia , Neapolis , Nukeria . Earthquakes continued with increasing frequency in subsequent years. They, of course, indicated an imminent eruption. But it was not so easy to believe that a big city could cease to exist - life in Pompeii and other nearby cities went on as usual.
Death of Pompeii
The tragedy happened (or rather, began)24 August 79 We know about it in some detail not only thanks to archaeological excavations, but also letters from a famous political figurePliny the Younger . So, at about two o'clock in the afternoon on August 24, a giant cloud began to grow rapidly over Vesuvius. white with brown spots. It rose into the sky and at some height spread out to the sides, resembling the crown of a Mediterranean pine. Near the volcano I heard terrible roar and continuous tremors occurred, which were also felt in the city of Miseno, located about 30 km from the volcano.Pliny the YoungerI was just in this city. He wrote that the shaking was so strong that it seemed that everything was turning over, carts were thrown from side to side, tiles were falling off houses, statues and obelisks were collapsing.
A gas stream bursting from the depths of the volcano carried with it a huge amount of pumice fragments. During the 10-11 hours of continuous eruption, the column of ejected pumice reached a 20-kilometer height; every hour 15-25 cm of “balls” with a diameter of 1-3 cm fell onto the soil surface. By the way, this is not always remembered, but since the explosion was “stretched out” In time, many residents managed to leave Pompeii to a safer place. Slaves remained (to guard the property of their owners) and the most stubborn Pompeians, who did not want to leave their homes. At night, wide tongues of flame burst out from Vesuvius in some places and a huge column of fire rose.On the morning of August 25, the second stage of the eruption began. Hot heavy avalanches came down from the volcano.
The magma, saturated with gases, was dispersed upon exiting the upper part of the vent and fell from the slopes of the volcano in the form of scorching clouds. It was just such a hot cloud that strangled the remaining residents of the city. Most of the plaster casts of voids in the thickness of the ash that covered Pompeii show us people suffering from suffocation. From 6 to 9 am, ash and pumice “balls” fell from the sky, which finally buriedPompeiiAndStabia. (The cities were buried up to the very roofs of the houses.) On the western slopes of the volcano they walked heavy showers. Loose ash and pumice accumulations on the slopes of the volcano, saturated with water, rushed down in hot mud streams. Three such streams covered the cityHerculaneum, located on the seashore, destroying all life in the blink of an eye. (According to other sources, residents in this wealthy fishing village also died from suffocation.)
Pliny the Younger describes what happened on the 25thMiseno. In the morning, a black cloud of ash began to approach the city. Residents fled in horror from the city to the seashore (probably residents of the dead cities tried to do the same). The crowd running along the road soon found itself in complete darkness; screams and crying of children could be heard. Those who fell were trampled by those following. I had to shake off the ashes all the time, otherwise the person would instantly fall asleep, and those who sat down to rest would no longer be able to get up. This went on for several hours, but in the afternoon the ash cloud began to dissipate.
Plinyreturned toMiseno, although earthquakes continued. By the evening the eruption began to decline, and on the 26th everything calmed down in the evening. Pliny the Younger was lucky, but his uncle, the outstanding scientist and author of natural history Pliny the Elder, died during the eruption in Pompeii. They say that the curiosity of a natural scientist let him down, he stayed in the city for observations. The sun over dead cities -Pompeii, Stabiae, HerculaneumAndOctavianum – It seemed only August 27th. Vesuvius has erupted at least eight more times to this day. Moreover, in 1631, 1794 and 1944 the eruption was quite strong.
Pompeii today
For many centuries, in the place where olive trees once grew and vineyards grew green, dull gray plains of frozen lava stretched. IN late XVI V. The architect Fontana, while digging a well near Sarno, accidentally found the remains of a wall and fragments of frescoes. But the first excavations of Pompeii began later - in the 18th century. For historians, the discovered Pompeii is a real treasure. In the city, covered with ash and pumice, houses, mosaics, and dishes were preserved. Now tourists walk along the cleared streets of Pompeii, fully feeling the atmosphere of the ancient Roman metropolis and at the same time realizing the scale of the tragedy that happened here in the summer of 79 AD. e.
Appendix B
Eruption of Mont Pele volcano
On May 8, 1902, the Mont Pelee volcano exploded, flying into pieces, which destroyed one of the main ports of the island of Martinique, Saint-Pierre, along with its population. In the blink of an eye, 36,000 people died.
Since the emissions did not come through the top of the volcano, but through side craters, all volcanic eruptions of this type have since been called “Peleian ».
Mont Pelée is located in the northern part of the island of Martinique. It rises 1,350 meters above the town of Saint-Pierre, the largest settlement on the island with a population of 32,000.
According to the writer Lafcadio Hearn, who visited the city before the eruption of Mont Pele, it was the “very, very” city. This is how he expressed his feelings: “... The most quaint, most unusual and at the same time the most beautiful city among the cities of the West Indies; built entirely of stone, with stone-paved streets, narrow streets, wooden or zinc canopies, and gabled red-tiled roofs pierced by dormers...”
That this stone architecture would be reduced to small pebbles in a matter of minutes was probably beyond the wildest imagination of the builders of Saint-Pierre. Not a single eruption of Mont Pele before 1902 gave any hint that it was a dangerous volcano. The 1767 eruption killed 16,000 people, but most died on the slopes of the volcano. Since then, its eruptions have become weaker and weaker.
Although the May eruption was a warning, hardly anyone in the local government or the local press paid attention to it. So, on April 2, quite strong jets of steam began to emerge through some holes on the mountainside. On April 23, ash with a distinct smell of sulfur fell onto the streets of Saint-Pierre, and dishes fell from the shelves from the aftershocks.
Starting from April 25, more noticeable, although not very alarming, signals of an approaching disaster began to appear. For example, there were explosions in the crater. And those who dared to approach the crater on Pele Etang Sek heard the sounds of boiling. Then the crater was filled with a boiling lake up to 200 meters wide. A 10-meter fountain of superheated water appeared next to him.
On April 27, ash fall increased. It blocked some roads and gave the landscape a winter look. In addition, there have been reports of animals and birds suffocating from poisonous gas, which came from the ashes.
The local newspaper "Des Colonies" described the end of April in Saint-Pierre this way: “The rain of ash does not stop for a minute. At about half past nine the sun came out timidly. You can no longer hear the noise of the stream of carriages on the streets. The wheels sink into ashes. Gusts of wind sweep away ashes from roofs and dormer windows and blow it into rooms whose windows were unwisely left open.”
And then the population of Saint-Pierre became worried. Big number residents left the city, but their place was immediately taken by more large groups refugees from the slopes of the mountain. The wife of the US Consul, Mrs. Thomas T. Prentice, wrote to her sister: “My husband assures me that there is no immediate danger, and if there is the slightest hint we will leave the city. The American schooner R. J. Morse is in port and will remain for at least two more weeks. If the volcano begins to threaten, we will immediately board a ship and go to sea.”
After the disaster on May 8, rescuers will find the charred corpse of the consul in a chair in front of the window overlooking Mont Pelée. In the next chair was the similarly charred corpse of his wife. The bodies of their children were never found.
But until that day, crowds of praying townspeople filled the local cathedral. One resident wrote on May 4 to his relatives in France: “I calmly await this event... If death awaits us, then we will leave this world in a large company. Will it be fire or suffocation? Whatever the Lord wills will happen.”
The animals turned out to be not so calm. “Des Colonies” wrote: “In the pastures, animals behave anxiously - desperately moo, roar, bleat.” At the large Usin-Guerin sugar factory, located at the mouth of the Blanche River, in the northern part of the city, an incredible infestation of ants and centipedes interfered with work in all areas. The horses in the yard neighed, kicked, and reared, as ants and centipedes climbed up their legs and bit. Grooms doused the horses with buckets of water, trying to wash away the insects. Inside the premises, workers beat centipedes with sugar cane stalks, and at the nearby villa of the factory owner, maids tried to get rid of them using irons and boiling water.
Meanwhile, in one of the quarters of Saint-Pierre, snakes driven out of their nests by a stream of hot ash filled the streets and courtyards. They killed chickens, pigs, horses, dogs and people who got in their way. That day, 50 people and 200 animals died from snake bites.
On May 5, heavy rains that poured onto the mountain caused streams of brown water in all the valleys of the southeastern slope of Mont Pele. That same day, shortly after noon, the same sugar factory that was experiencing an insect attack was buried under a huge mud avalanche with many huge boulders and trees. Rolling down the mountains, the avalanche engulfed the plant in a matter of minutes, drowning 150 people in boiling mud and leaving only pipes on the surface. Having dealt with the plant, the avalanche moved towards the sea. There she created a huge wave that capsized two anchored ships and flooded the lower city of St. Pierre.
The newspaper Des Colonies wrote: “A stream of people rushed from the lowest point of Moulage. It was a flight in search of safety, not knowing where to run. The whole city was in motion. Shops and private homes are closed. Everyone is preparing to seek shelter on higher ground."
And then one of the most cynical events in history happened. In an effort to keep the population in Saint-Pierre during the approaching elections scheduled for Sunday, May 10, the French governor appointed a commission to investigate the danger posed by Mont Pelée. “Des Colonies” reported: “Professor Landes of Lycée concluded that the Mont Pele volcano poses no greater danger to the inhabitants of Saint-Pierre than Vesuvius does to the population of Naples... We admit that we cannot understand this panic. Where can you feel better than in Saint Pierre? Do those who filled Fort-de-France believe that they would be better off than here if there was an earthquake?
In order to give the commission's findings special weight, the governor gave the troops the order to return the refugees to the city. And to further reassure potential voters, the governor and his wife traveled from Fort-de-France to Saint-Pierre, where a day later both met a fiery death.
All day on May 7, Mont Pele erupted continuously. But the residents of Saint-Pierre were a little cheered by the news that the Soufriere volcano, located 145 kilometers to the south, on the island of Saint Vincent, had exploded. Going to bed on the last night of their lives, the residents of Saint-Pierre thought that Soufrière's explosion would reduce the pressure on Mont Pelée and perhaps carry it away.
The dawn of May 8 was clear and the day promised to be sunny. The column of steam from the Mont Pele crater rose higher than usual, but other than this there was nothing exceptional or strange in the behavior of the volcano. At about 6:30 a.m., the Roraima, its decks covered in ash, entered the port of Saint-Pierre and anchored alongside 17 other ships.
And at 7.50 Mont Pele was torn to pieces. More precisely, 4 explosions sounded, deafening, similar to cannon shots. They threw out a black cloud from the main crater, which was pierced by flashes of lightning. But this was not the most dangerous release. It was the lateral emissions - those that from that time would be called "Peleian" - that sent fire and brimstone at hurricane speed along the mountainside directly to St. Pierre. In 2 minutes, all but 4 people of the more than 30,000 population of St. Pierre were reduced to ashes. They either burned instantly or instantly suffocated.
All the houses, all the buildings of Saint-Pierre exploded or were partially destroyed. All the leaves and branches were torn off from the trees, leaving only bare trunks. Stone and concrete walls up to a meter thick, it was torn into pieces as if they were made of cardboard. The six-inch cannons on the Norn d'Orange were torn from their mounts, and the statue of the Virgin Mary, weighing at least 3 tons, was carried 15 meters from its base by the stream. Thousands of barrels of rum exploded on the piers and warehouses of the port, the fiery liquid spread through the streets and flowed in streams into water near the pier.
Not surprisingly, there were no survivors. The superheated volcanic gas, due to its high density and high speed of movement, spread above the ground itself, penetrated into all the cracks and corners, leaving no one a chance of salvation. Even 3.5 hours after the release - at 11.30 - the burning city was “breathing” so hotly that the ship from Fort-de-France could not approach the shore.
A strong gust of wind capsized most of the ships in the port, and their crews and passengers died in the boiling water. The day before, perhaps the wisest of the captains in the port of St. Pierre, a Neapolitan named Marino Leboff, who commanded the Italian barque Orsolina, disregarded the decision of the port authorities, who did not allow him to sail, and left the port. “I don’t know anything about Mont Pelé, but if Vesuvius looked the way your volcano looks this morning, I would run away from Naples as fast as I could,” he said in parting.
16 of the 18 ships in the harbor capsized at the time of the explosion. The steamer Roraima found itself in the thick of a black cloud. Assistant steward Thompson recalled the minutes before the eruption, when the crew, along with the captain (who later died), gathered to look at the view of the erupting volcano.
Thompson said: “The spectacle was monstrous and magnificent... We could see rolling and jumping red tongues of flame, which burst out of the mountain in huge numbers and hit the sky in a high stream. Huge clouds of black smoke hung over the volcano. Then the flame shot straight up, from time to time leaning for a moment to one side or the other and again jumping sharply even higher. A constant muffled roar was heard. It looked like the world's largest oil refinery was located on top of the mountain. There was a terrifying explosion... The mountain shattered into pieces. There was no warning. The slope of the volcano broke away, and from there a dense wall of fire rushed straight towards us. It made a sound like the shots of a thousand guns. A wave of fire rushed like a flash of lightning. It looked like a fiery hurricane that was rolling straight towards St. Pierre and the ships. The city disappeared before our eyes, and then the air became suffocatingly hot, and we found ourselves in the thick of it. Wherever the mass of fire touched the sea, the water boiled and huge clouds of steam appeared... Before the volcano exploded, the surroundings of Saint-Pierre were crowded with people. After the eruption, not a single living soul was visible on earth..."
Roraima's senior officer, Ellary Scott, described the moment the strike occurred: “It was as dark as night. "Roraima" swayed and heeled, then with a sharp push it lay on the starboard side, plunging its protective rails deep into the water. The masts, chimney, rigging - everything was completely washed away and disappeared overboard. The iron smokestack came off and two steel masts broke 60 centimeters above the deck. Fires broke out in several places at the same time, and men, women, and children died within seconds.”
Only two of the passengers - a little girl and her nanny - survived. Later, the brilliant Harvard geologist Dr. Thomas Jagger spoke with them. The nanny’s story was especially vivid:
“... The steward rushed (he later died) past the cabin where I was helping the children get dressed for breakfast, and shouted: “Close the cabin door - the volcano is approaching!” We closed the door, and at the same moment there was a terrible explosion, from which our eardrums almost burst. The ship rose high into the air, and then it seemed to keep sinking and sinking. The blow knocked us off our feet and we huddled in one corner of the cabin.
An explosion seemed to be heard in the sky above our heads, and before we could rise, hot, wet ash fell upon us; it fell in boiling flakes, like liquid mud without a single piece of stones...
The next sensation was suffocation, but when the door swung open, air rushed in, and we came to our senses a little. When we saw each other's faces, they were covered with black mud, the baby was dying. Rita, the eldest girl, suffered terribly, and my whole body ached. A pile of hot mud accumulated near us, and when Rita lowered her hand to rise, it rose in a scalding mass up to her elbow...”
A huge volcanic cloud covered the area of complete destruction. The second zone of destruction stretches another 60 square kilometers. This cloud, formed from super-hot steam and gases, weighed down by billions of particles of hot ash, moving at a speed sufficient to carry rock debris and volcanic emissions, had a temperature of 700-980 degrees Celsius and was able to melt glass.
It took 4 days for the city to come to life so that rescuers could enter it. In the city, rescuers saw unbearable pictures of terrible destruction. The tanks at the distillery, which were massive tanks made of 6mm iron welded together, burned out.
One observer noted: “It was as if artillery fire had been fired at them - they were covered with holes of various sizes: from small cracks to huge gaps of 60, 75 and 90 centimeters on the sides.”
Two weeks later, those arriving on the American rescue ship "Dickie" saw, according to Angelo Heilirin of the Philadelphia Geographical Society, "twisted iron beams, huge masses of roofing wrapped like rags around the posts on which the wind had thrown them; beams tied in a loop and hung with garlands as if they were made of ropes."
They discovered the charred corpses of people having breakfast at tables that, due to the selective nature of the capricious cloud that killed people, were served with intact plates, cutlery, and glasses.
A charred woman was found with a completely untouched handkerchief pressed to her lips. Many bodies lay naked - a strong gust of wind tore off their clothes. IN jewelry store the temperature turned out to be so high that it melted hundreds of clock mechanisms into one lump, and nearby, in the kitchen, there were bottles of water, sealed with caps, standing intact and undamaged. Nearby are bags of starch, where the granules remained untouched.
Only 4 people survived the disaster on May 8, 1902. Two were outside the city. One of them is a girl named Harviva de Ilfrail. She told a woeful story about how, halfway up the mountain, on behalf of her grandmother, she looked into the “boiling substance” coming out of the so-called “spiral crater.” She ran to the harbor and jumped into her brother's boat and turned to see her brother running ahead of the boiling wave of ash. “But he was too late,” she said. “And I heard him scream piercingly as the stream first touched and then swallowed him.”
From the harbor, a little girl somehow took the boat out and got to a small grotto where she once played with her friends. “But before I got there, I looked back: the entire mountainside near the city seemed to open up and fall on people in a boiling stream; I was burned many times by stones and ashes flying near the boat, but I made it to the cave,” – she finished.
Another surviving resident of Saint-Pierre was 25-year-old longshoreman Auguste Chipari, who was in an underground prison at the time of the explosion. He later told his story to George Kennan and then became the main attraction for the Barnum & Bailey Circus. While under the protection of his underground prison, he nevertheless received extensive burns all over his body. Kennan called the burns "almost too terrible to describe."
Robbers poured into St. Pierre from other parts of the island of Martinique. French sailors from the cruiser Suchet shot 27 of them.
Months passed before all the inhabitants of St. Pierre could be buried. During this time, Mont Pele erupted again - on May 20 - with almost the same force as on May 8. The remaining walls in St. Pierre were destroyed and another 2,000 died. Almost all of the dead were rescuers, engineers and sailors who delivered help to the island.
A ship with spare food and scientists from the United States arrived several hours after the second eruption. The scientists stayed for months, and Mont Pele gave them one last, more merciful performance. Sometime in mid-September, a dome-shaped mass of lava, too thick to flow, formed something like a pillar or obelisk in the Etang Sek crater. Its diameter was 100-150 meters, and after a few months it reached a height of 310 meters above the base of the crater or 1585 meters above sea level. It was twice as tall as the Washington Monument and as large as the Pyramids of Giza.
But it was too unstable to last long. And by September 1903 it collapsed. By that time, scientists from the Dickey had photographed it, preserving it for centuries. And while the obelisk stood, it seemed to the scientist Angelo Heilirin “a natural monument in honor of the 30,000 dead who remained lying in the silent city at its foot.”
Internal structure of the Earth
Shell name
Size (thickness)
State
Temperature
Pressure
Percentage
Earth's crust
5–80 km
Solid
Various, from -7°С to +57°С
760 mm. Hg Art.
Upper mantle
200–250 km
Plastic, softened
2000°C
1.3 million atm.
82%
Lower mantle
2900 km
Solid, crystalline
Outer core
2250 km
Molten, liquid
2000–5000°С
3.6 million atm.
17%
Core internal
1250 km
Solid
Find a match (drag and drop method).
Core
Layer thickness 5–10 km
Mantle
Temperature from +2000 °C to +5000 °C, solid state
Continental crust
IN
Temperature +2000 °C, viscous state, closer to solid, consists of two layers
4
Oceanic crust
G
Consists of granite, basalt and sedimentary rocks.
There are currently approximately 1,300 active volcanoes on land. There are also many of them under water, but their number fluctuates, as some cease their activity, while others arise. Every dormant volcano can suddenly explode. Consequently, those volcanoes that have been active at least once over the past 10 thousand years are considered active.
Appendix B
Glossary of terms
Vulcan - what is it?
A volcano is a naturally occurring hole in the earth's crust through which hot molten rock called lava, as well as gases, steam and ash (what remains after a solid substance has completely burned) burst out, often in large and noisy eruptions or explosions.
These eruptions are thought to act as safety valves, releasing enormous amounts of heat and pressure deep within the earth. Typically, a volcano is a cone-shaped mountain (the walls of which consist of solidified lava and ash) with a hole in the center, or a crater, through which eruptions occur. There are several different types, or stages, of an eruption. Many eruptions do not cause significant damage to the environment. But there are very powerful and destructive eruptions. During such eruptions, lava can spill out and flow down from the volcano, flooding the surrounding areas; choking clouds of steam, ash, hot gases and stones can fall down, which descend to the ground at high speed, covering it for many kilometers around. (When Mount St. Helens on Mount Washington erupted in 1980, for example, it killed millions of trees.)
One of the most famous and destructive was the eruption of Mount Vesuvius (located in today's Italy) in 79 AD. As a result, the large Roman city of Pompeii was destroyed. A huge cloud of ash and ash covered the city, thanks to which it has been well preserved to this day. By studying these amazing ruins, scientists have learned a lot about the times of Ancient Rome.
Eruptions are not always accompanied by outpourings of lava. Explosive eruptions occur very often, releasing huge amounts of debris. 
One of the most famous tragedies is associated with the eruption of Mount Vesuvius and the destruction of the cities of Pompeii and Herculaneum. It is believed that they were filled with lava and covered with ash, which fell like rain, but the lava moves slowly. The fastest lava flows flow at a speed of no more than 1-2 m/s. You can still escape from such a fast flow and rise to the top. Something different was happening in Pompeii. An explosive volcanic eruption led to the rapid death of the townspeople. Debris flew for 5-10 km, the effect of which was comparable to bombs. This is the most dangerous eruption. The gas-saturated flow moves at high speed, pushing hot air ahead of it.
Types of volcanoes
A volcanic eruption can last for several days, sometimes months and even years. After a strong eruption, the volcano calms down again for several years and even decades. Such volcanoes are calledvalid .
There are volcanoesextinct , which erupted in times long past, no information has been preserved about their activities. These include Elbrus and Kazbek, peaks in the Caucasus covered in sparkling, dazzling white glaciers.
In ancient volcanic areas, severely destroyed and eroded volcanoes are found. Some extinct volcanoes have retained the shape of a regular cone. In our country, the remains of ancient volcanoes can be seen in Crimea, Transbaikalia and other places.
Volcanoes are usually cone-shaped with slopes that are gentle at their bases and steeper at their summits. If you climb to the top of an active volcano when it is calm, you can see a crater - a deep depression with steep walls, similar to a giant bowl. The bottom of the crater is covered with fragments of large and small stones, and jets of gas and steam rise from the cracks. Some jets rise calmly, others burst out with hissing and whistling. The crater is filled with choking gases, forming a cloud at the top of the volcano. So the volcano can quietly smoke for months and years until an eruption occurs.Volcanologists have developed methods that make it possible to predict volcanic eruptions. An eruption is often preceded by earthquakes, underground rumble, increased release of vapors and gases, clouds thicken over the top of the volcano, and its slopes begin to “swell.” Under the pressure of gases escaping from the bowels of the Earth, the bottom of the crater explodes. From the black, thick clouds, along with fire, ash and hot stones, heavy rains fall, forming streams of mud that roll down the slopes and flood the surrounding area. The volcano rumbles and trembles, seething fiery liquid lava rises through its mouth. Overflowing over the edges, it rushes along the slopes, burning and destroying everything in its path.
If lava has a high viscosity, it does not pour out as a liquid stream, but is piled up around the vent in the form of a volcanicdomes . During collapses or explosions, hot rock avalanches fall from the edges of such a dome, which can also cause great destruction at the foot of the volcano.
During weaker eruptions, only periodic explosions of gases occur in the volcano's crater.
Volcanic eruptions also occur at the bottom of seas and oceans. Sailors learn about this when they suddenly see a column of steam above the water or “stone foam” floating on the surface - pumice. Sometimes ships encounter unexpected shoals formed by new volcanoes at the bottom of the sea. Over time, these shallows are eroded by sea waves and disappear without a trace. The cones of some underwater volcanoes protrude above the surface of the water in the form of islands.
In ancient times, people did not know how to explain the causes of volcanic eruptions. This formidable natural phenomenon plunged people into horror. However, already the ancient Greeks and Romans, and later the Arabs, came to the idea that in the depths of the Earth there is a sea of underground fire, and that the disturbances of this sea cause volcanic eruptions.
Volcanologists constantly monitor volcanoes. Volcanological stations - observatories have been organized near some active volcanoes.IN THE USSRSuch stations are located in Kamchatka at the foot of the Klyuchevsky volcano in the village of Klyuchi and on the slope of the Avacha volcano. Volcanologists also study extinct and destroyed volcanoes. The accumulation of such observations and knowledge is very important for geology. Volcanoes, which were active tens of millions of years ago and almost leveled with the surface of the Earth, help scientists establish how molten masses from the bowels of the Earth penetrate into the solid crust and what results from their contact with rocks. Usually, in places of such contact, ores of iron, copper, zinc, etc. are formed as a result of chemical processes.
Jets of steam and volcanic gases in the craters of volcanoes, which are calledfumaroles , carry with them some substances in a dissolved state. Sulfur, ammonia, and boric acid are deposited in the cracks of the crater and around it, around the fumaroles, which are used in various industries.
Volcanic ash and lava contain a lot of potassium and over time turn into fertile soils. Therefore, although it is unsafe to live in the vicinity of volcanoes, villages and cities almost always grow there.
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Vesuvius still remainscurrent volcano; this means that it experiences volcanic activity and eruptions occur from time to time. There are also volcanoes that are described asinactive , this means that there has been no activity in them for a long time, but the conditions for a possible eruption in the future still exist.Extinct - This is a volcano that will never erupt again.
Volcanoes often occur in places where there are tectonic plates or ridges in the earth's crust. Around the Pacific Ocean, where the plates of the Earth's crust meet, there is a group of volcanoes known as the "Ring of Fire." Due to the movement of tectonic plates in these areas, liquid rock (called magma) trapped in voids within the Earth can rise, causing volcanic activity. (This also often causes earthquakes.)
Volcanic activity can occur both on land and in the oceans. As a result, islands sometimes form in the oceans. This is how the Hawaiian Islands appeared about 40 million years ago. And even today, two of the most active volcanoes - Mauna Loa and Kilaua - are located on an island in Hawaii. Tourists visiting Hawaii Volcanoes National Park can hike the slopes surrounding the great volcanoes.
BIBLIOGRAPHY
Website WHY. Answers to questions for parents and their children. , 12/19/2014
Country Russia
Genre: Educational
Duration: ~25 min.Description: Don't awaken the beast in me! Which alarm clock guarantees a comfortable awakening? Mold in the house: can it be eliminated without making repairs? And also - the truth and myths about the cold: how is it dangerous and how not to get sick in winter?
Our The site was created specifically for people interested documentary films. The site is gradually gaining popularity among users and this , at the moment, documentaries have been added in the amount of
Video Is it possible to predict earthquakes and volcanic eruptionshttp://xn--80aeegmdk5ce.xn------8cd0bkjdfndh5e7en.xn--p1ai/load/nauchno_poznavatelnye_filmy/atlanty_v_poiskakh_istiny/mozhno_li_predskazat_zemletrjasenija_i_izverzhenija_vulkanov_mir_nauchno_pop uljarnykh_filmov/365-1-0-2612
Pompeii
Galens Judy, Nancy's Feast Book of answers for why: Trans. from English – Kharkov: Book Club “Family Leisure Club”, 2006.
