What are the changes in the eruption of the volcano. Questions and tasks. Main types of volcanoes

The harbinger of volcanic eruptions are volcanic earthquakes. Special instruments record changes in the inclination of the earth's surface near volcanoes. Before the eruption, the local magnetic field and the composition of volcanic gases change. In areas of active volcanism, special stations and points have been set up, in which continuous monitoring of volcanoes is conducted to warn them in time of their awakening. So, in Kamchatka in 1955, the volcanic Bezymyannyi volcano was predicted, in 1964 - Shiveluch volcano, then - Tolbachik volcanoes.

The only way to save people during eruptions of volcanoes is the evacuation of the population. The speed of the spread of lava is low, but it burns everything in its path. There is an intense release of volcanic ash, which impairs visibility, as well as hot stones. These stones destroy buildings, cause fires, terrify people.

The dangerous impact of relatively slow lava flows can be reduced in three ways:

Decline the flow;
  divide it into several smaller ones;
  stop by cooling, creating an earth wall, masonry, etc.

So, in 1960 during the eruption of the volcano Kilois, the foreman of the local fire department was jumped by the authorities for the decision to pour lava on the village. Meanwhile, the lava was cooled and frozen. After 13 years, in 1973, his brave example was followed by the Icelanders during the eruption of the volcano Kirchefeld. By feeding water from the sea to the lava stream, it was possible to stop the catastrophe.

It brings success and the division of the lava flow into several branches.

In 1935 on the Hawaiian Islands, a lava flow from the Mauna Loa volcano threatened the city. The bombardment of the stream from the aircraft was successfully carried out, the lava spread over the slopes and froze. The deadly stream that threatened the city was stopped in two days.

Sometimes bombardment is also used to destroy the crater wall and the direction of the lava flow in a safe direction.

An additional danger to people is the mud streams formed from the fallen rain and ash, moving at relatively high speeds. At the same time, one can be saved by sending such a stream to a safe direction, for example, in a reservoir.

Abundant fallout of ash is dangerous in that it accumulates in large quantities on the roofs of houses. In this case, it must be dropped downward.

The biggest danger is the "scorching cloud", from which you can escape only by flight.

It is necessary to remember that the forces of nature, concealed in volcanoes and other elements, are much larger than human ones. Nature must always be treated with respect.

The most reliable and safe way to protect yourself from a volcanic eruption is to choose a place of residence away from active volcanoes.

Since an earthquake occurs before the eruption of the volcano, all the rules of human behavior during it are actual in the case of a volcanic eruption.

Six of the most deadly volcanic eruptions

1. Vesuvius, 79 year of our era, killed at least 16 thousand people.

This eruption was known to historians from the letters of the eyewitness, poet Pliny the Younger to the ancient Roman historian Tatsiata. During the eruption, Vesuvius threw out a deadly cloud of ash and smoke at a height of 20.5 km, and also spewed about 1.5 million tons of molten rock and crushed pumice every second. At the same time, a huge amount of thermal energy was allocated, which many times exceeded the amount that was generated during the explosion of the atomic bomb over Hiroshima.

So, within 28 hours after the beginning of the eruption, the first series of pyroclastic flows (mixture of incandescent volcanic gases, ash and stones) descended. The currents overcame a huge distance, almost reaching the Roman city of Miseno. And then another series came down, and two pyroclastic flows destroyed the city of Pompeii. Subsequently, the cities of Oplontis and Herculaneum, located near Pompeii, were buried beneath volcanic sediments. Ashes also reached Egypt and Syria.

The famous eruption was preceded by an earthquake that began on February 5, 62. According to researchers, the earthquake was a magnitude from 5 to 6. It led to large-scale destruction around the Bay of Naples, where in particular the city of Pompeii was located. Damage to the city was so strong that they could not be eliminated even at the beginning of the eruption itself.

It is important to note that the Romans, as Pliny the Younger wrote, are used to periodic earthquakes in this region, so they were not particularly alarmed by this earthquake. However, since August 20, 79 earthquakes have become more frequent, but still not perceived by people as a warning of the impending catastrophe.

It is interesting that after 1944, Vesuvius is in a fairly calm state. However, scientists suggest that the longer a volcano is inactive, the stronger will be its next eruption.

2. Udzen, 1792, killed about 15 thousand people.

After the eruption took place in 1792, it remained inactive for 198 years, until the eruption that occurred in November 1990. Currently, the volcano is considered to be weakly active.

This volcano is part of the Japanese peninsula of Simabara, which is characterized by frequent volcanic activity. The oldest volcanic deposits in this region are over 6 million years old, and extensive eruptions occurred between 2.5 million and 500 thousand years ago.

However, the most deadly eruption occurred in 1792, when lava erupted from the volcanic dome of Fujin-deik. After the eruption, an earthquake followed, because of which the edge of the Mayu-Yam volcanic dome began to crumble, creating a landslide. In turn, the landslide provoked a tsunami, during which the waves reached 100 meters in height. Because of the tsunami killed about 15 thousand people.

According to the results of 2011, the magazine The Japan Times called this eruption the most horrible of all that ever happened in Japan. Also, the eruption of Unzen in 1792 is among the five most destructive eruptions in the history of mankind in terms of the number of human casualties.

3. Tambora, in 1815, killed at least 92 thousand people.

April 5, 1815, there was an eruption of the volcano Tambora, located on the Indonesian island of Sumbawa. It was accompanied by rumbling sounds that were heard even 1,400 km from the island. And on the morning of the next day volcanic ash began to fall from the sky and sounds resounding like the noise of guns firing in the distance. By the way, because of this similarity, a detachment of troops from Jogjakarta, an ancient city on the island of Java, thought that an attack had been committed on the neighboring post.

The eruption intensified on the evening of April 10: the lava began to flow, completely covering the volcano, and a "rain" of pumice with a diameter of up to 20 cm began. This was accompanied by the flow of pyroclastic flows from the volcano to the sea, which destroyed all the villages on its way.

This eruption is considered one of the largest in human history. During it, explosions were heard at 2600 km from the island, and the ashes reached at least 1300 km. In addition, the eruption of the Tambora volcano provoked a tsunami, during which the waves reached 4 meters in height. After the disaster, tens of thousands of inhabitants and animals of the island were killed, and all vegetation was destroyed.

It is important to note that during the eruption an enormous amount of sulfur dioxide gas (SO2) hit the stratosphere, which subsequently led to a global climatic anomaly. In the summer of 1816 extreme weather conditions were observed in the countries of the northern hemisphere, because of which the 1816th was named "The Year Without Summer". At that time, the average global temperature dropped by about 0.4-0.7 ° C, which is enough to cause significant problems in agriculture around the world.

So, June 4, 1816 in Connecticut, there were frosts, and the next day the majority of New England (a region in the northeastern United States) was covered by the cold. Two days later, snow fell in the cities of Albany, New York State and Dennisville, Maine. Moreover, such conditions lasted at least three months, because of which the majority of crops in North America died. Also, low temperatures and heavy rains led to a loss of yield in the UK and Ireland.

4. Krakatoa, 1883, killed about 36 thousand people.

Before the catastrophic eruption of the Indonesian volcano Krakatau in 1883 on May 20, the volcano began to produce a large amount of smoke and ash. This lasted until the end of the summer, when on August 27 a series of four explosions completely destroyed the island.

The explosions were so strong that they were heard at 4800 km from the volcano on the island of Rodriguez (Mauritius). According to the researchers, the shock wave from the last explosion spread around the world seven times! Ashes rose to a height of 80 km, and the sound of the eruption was so loud that if someone was 16 km from the volcano, he would certainly be deaf.

The emergence of pyroclastic flows and tsunamis had catastrophic consequences both in the region and throughout the world. According to the government, the death toll was 36,417, although some sources claim that at least 120,000 people died.

It is interesting that the average global temperature during the year after the eruption of Krakatoa has decreased by 1.2 ° C. To the former temperature returned only in 1888.

5. Mont-Pele, 1902, killed about 33 thousand people.

In April 1902, the awakening of the volcano Mont Pelay located in the north of the island of Martinique (France) began. And on the evening of May 8, an eruption suddenly began. A gas-ash cloud began to rise from the crack at the foot of Mont-Pele.

Soon a hurricane of hot gases and ash reached the Saint-Pierre, located 8 km from the volcano, and in a few minutes destroyed it and 17 steamships standing in its harbor. "Roddam", suffered multiple destruction and "powdered" with ashes, was the only ship that managed to get out of the bay. The strength of the hurricane can also be judged by the fact that the monument weighing several tons was thrown a few meters from its place in the city.

Arrivals, almost all the population and animals died during the eruption. Only two people survived by a miracle: prisoner of the local prison August Sibarus, who was sitting in an underground solitary cell, and lived on the outskirts of the town cobbler.

6. Nevado del Ruiz, 1985, more than 23 thousand people.

Since November 1984, geologists have observed an increase in the level of seismic activity near the volcano Nevada del Ruiz (Colombia), located in the Andes. And on the afternoon of November 13, 1985, this highest active volcano of the Andean volcanic belt began to erupt, throwing ash into the atmosphere to a height of more than 30 km. The volcano produced pyroclastic flows, under which melted ice and snow in the mountains - there were large lahars (mud volcanic flows). They descended down the slopes of the volcano, eroding the soil and destroying vegetation, and eventually fell into six river valleys leading from the volcano.

One of these lahars practically washed away the small town of Armero, which lay in the valley of the river Lagunilla. Only a quarter of its residents (a total of 28,700 people) survived. The second stream, which descended the valley of the Chinchin River, killed about 1800 people and destroyed about 400 houses in the city of the same name. In total, more than 23 thousand people were killed and about 5 thousand were injured.

The eruption of Nevado del Ruiz in 1902 is considered the most terrible natural disaster that occurred in Colombia. The death of people during his time was partly due to the fact that scientists did not know when the eruption would occur, because the last time it happened 140 years ago. And since it was not known about the imminent danger, the government did not take expensive measures.

QUESTIONS AND TASKS

1. What do you know from the history of volcanoes?

2. What are the volcanoes and what is their danger?

3. How does the volcano work?

4. What natural disaster accompanies the volcanic eruption?

5. Name and show on the map of our country active and extinct volcanoes.

6. Show on the map the main belts of volcanic activity.

7. What are the dangerous volcanic eruptions and their consequences?

8. List the main ways to reduce damage from volcanic eruptions.

9. What is the procedure for declaring a threat of a volcanic eruption?

10. Find out if it is possible in your locality to erupt a volcano, where it is, when there was a last eruption, whether there are extinct volcanoes.

The scientists made a unique discovery. The eruption of the volcano, which happened recently in Iceland, and was even more powerful than last year, coincided with the eruption of a volcano ... on Jupiter. Have such coincidences occurred before? And is it possible, when observing the volcanic activity on other planets of the solar system, to predict such events on our Earth?

May 21, after seven years of rest, the most active volcano of Iceland woke up. Within a short time, an enormous column of ash exploded into the atmosphere, the trail behind it subsequently stretched for 20 kilometers. Scientists report that other volcanoes are becoming active. If they all wake up from hibernation in the near future, the Earth will be in an extremely difficult situation.

At first glance this may seem delusional, but scientists believe that volcanic activity can be the cause of volcanic activity on Earth. The fact that somehow terrestrial volcanoes can be influenced by their relatives on other planets was established by Soviet astrophysicists back in the late 1980s. To this unexpected conclusion, scientists came during the observation of the satellite of Jupiter Io.

As it turned out, Io - the most restless heavenly body in the entire solar system. Every day, up to 10 volcanic eruptions are recorded on its surface. And this despite the fact that all of them on the surface of the satellite about 400. When the eruption up, huge columns of sulfur dioxide gas rise. It happens that the height of these emissions reaches 300 kilometers.

Long-term observations of Io showed that in those times when the largest volcanoes begin to erupt on Io, seismic activity also increases on Earth. Part of this theory was confirmed in 2002, when its most powerful Loki volcano began to erupt on the satellite of Jupiter. This event was detected by an autonomous spacecraft operating in orbit of Io. The volcano's ejection was so powerful that it reached a 500-kilometer altitude, and the station, flying through this fountain of gas, managed to take samples. Chemical analysis made it possible to find out that Loki erupted from ash and lava. The most interesting was the fact that a few calendar months later a series of natural disasters occurred on our planet.

The summer of 2002 in Europe was marked by a severe flood. Usually at this time such natural phenomena are not observed, but this time in the Czech Republic, for example, the flood was the most devastating since 1500. Strongly affected by this phenomenon and neighboring countries - Austria, Germany, Romania, Hungary and Croatia. In the same 2002, the flood did not bypass Russia. Karachay-Cherkessia, Adygea, Stavropol and most of the Krasnodar Territory were under water. Storm rains in the anomalous amount caused significant damage. In particular, power lines, gas pipelines, and some communications were destroyed on the Black Sea coast. Thousands of families were affected by the flood, left homeless, the elements took with them more than a hundred human lives.

The second eruption of Loki was recorded at the end of 2004, and again scientists found a direct link to events on Earth scale. December 26 on the island of Sumatra in the northern part of it happened the most powerful earthquake with a magnitude of 9 points, which caused a fracture of the earth's crust for 600 kilometers. For this reason, tectonic plates on the bottom of the Indian Ocean began to move, which led to the emergence of the most powerful tsunami over the entire observation period. Waves up to twenty meters high hit the shores of Sri Lanka, India, Bangladesh, Thailand, Indonesia and even reached the coast of African Somalia, which is 5,000 kilometers from the epicenter of the earthquake.

The tragic earthquake in Japan, which occurred on March 11 of this year, led to the emergence of a powerful tsunami wave that claimed many lives. But a month before this event astronomers recorded another peak of activity of the Loki volcano on Io - the height of the fountain reached 400 km this time.

Scientists can not predict the activity of the Loki volcano in the future. To do this, Io needs to install a network of seismic sensors on the surface of the Io, this can help scientists learn more about volcanos of extraterrestrial origin, which in turn can prevent future catastrophes on our own planet.

Scientists firmly believe that such a network of sensors should be installed not only on Io, but also on our nearest neighbors - Venus and Mars, and even on our moon companion, where there are also volcanoes, although inactive. But they can wake up at any moment, which can be dangerous for the Earth.

The Institute, which monitors all volcanic eruptions, since the IXX century, cites data that indicate a steady increase in their number. The increase in volcanic activity is associated with an increase in activity of extraterrestrial volcanoes and it is already estimated that the peak will be in 2035. These events will trigger synchronous processes on our planet, scientists believe. Moreover, if the largest volcanoes wake up on our neighbors, they will provoke the eruption of their terrestrial counterpart - the huge volcano Yellowstone. Its size amazes imagination - the edges of the volcano lie in three different states - Montana, Wyoming and Idaho. The last time the volcano erupted more than 600 thousand lei back, so it is considered asleep.

At that time, an event of this magnitude led to disastrous consequences. Clouds of smoke and ash for a long time overshadowed the sky over North America, which resulted in a small ice age, which provoked the death of thousands of species of flora and fauna. If such an event occurs again, the consequences will be the most sad for the Earth. Both American continents will simply disappear, large disasters are expected in the rest of the planet.

In any case, no one doubts that this will be the most powerful eruption of the volcano in the history of mankind. A huge explosion of power can wake most of the volcanoes on the planet, and with this scenario, no one will survive. Today there are about 600 volcanoes on the Earth, which are active. But a huge number of volcanoes are in the depths of the sea. For example, only in the central regions of the Pacific Ocean there are about two hundred thousand, however, most of them are inactive and are waiting for their time.

There remains only one hope - that scientists will learn first to predict these terrible phenomena in space, and then will find opportunities to fight them on Earth.

Based on tainy.net