Description of the volcanic eruption. How the volcano works

Lesson plan:

• A bit of history

• What is a volcano?

• The structure of the volcano

• Types of volcanoes

• The importance of volcanoes in nature

• Quiz "Volcanoes"

What are volcanoes?

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

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

• The science that studies volcanoes is volcanology, geomorphology.

What is volcanism?

Volcanism is a complex

a process in which

magma rises

from the bowels of the earth, breaks through

  the earth's crust and

poured out on the surface

Products of volcanic eruptions

• Carbon dioxide

• Hydrogen sulfide

• Water vapor

• Lava

• Volcanic bombs

• Volcanic ash

Volcanoes are classified

• in form(thyroid, stratovolcano, slag cones, domes),

• activity   (active, sleeping, extinct),

• location   (terrestrial, submarine, subglacial)

Changing the Island of Krakatoa

Thyroid volcanoes are formed as a result of multiple releases of liquid lava. This form is typical for volcanoes erupting basalt lava of low viscosity: it flows from both the central crater and the slopes of the volcano. The lava spreads evenly over many kilometers. As, for example, on the Mauna Loa volcano in the Hawaiian Islands, where it flows directly into the ocean.

Yellow border posts serve to recognize the course of the road even in winter. The island has a well-developed road network. However, you often have to reckon with bridges on the road. In recent years, other important roads have been laid. However, the side roads and internal roads are clean gravel roads to this day. But even this speed can not and should not be set in motion on dry gravel roads.

Especially in dense fog, too optimistic tour planning takes revenge. Many roads cross rivers without bridges. Two road signs. Many Icelandic roads are accessible only with all-wheel drive. On them you can find fords up to 1 m deep, steep slopes and sandy soil. These routes should only be used by professionals. This is now even true for some mountain roads, such as Kjelur and Kaldilur. Icelanders themselves, especially those who were in Reykjavik, were in good times for reasons of status such as large SUVs, but were never going to actually drive in the area.

• Slag cones throw out from their vents only such loose substances as stones and: the largest fragments accumulate in layers around the crater. Because of this, the volcano with every eruption is getting higher. Light particles fly away to a further distance, which makes the slopes flat.

• Stratovolcanoes, or "layered volcanoes"periodically erupt lava and pyroclastic material - a mixture of hot gas, ash and red-hot stones. Therefore, deposits on their cone alternate. On the slopes of stratovolcano, ribbed corridors are formed from frozen lava, which serve as a support for the volcano.

• Dome volcanoes formed when a granite, viscous magma rises above the edges of the crater of the volcano and only a small amount seeps out, draining along the slopes. Magma clogs the vent of the volcano, like a cork, which the gases accumulated under the dome literally kick out of the vents.

• Active

• Sleeping

• Extinct

Klyuchevskaya Sopka is an active volcano

Hekla - active volcano

Vesuvius

Pinatubo

Elbrus - a sleeping volcano

Demovend is an extinct volcano

Than

are dangerous

active volcanoes?

The last day of Pompeii is a picture of K.P. Bryullov

The significance of volcanoes

• Formation of rocks of volcanic origin-basalt and tuff.

2. Education of warm and mineral springs

3. There is a power plant in Kamchatka that uses steam, which rises through wells from great depths.

fastening

fastening

What is lava?

What is a volcano crater?

What is a muzzle?

  Name the products

  Name the products

volcanic eruptions?

  What kinds of volcanoes

  you know?

Show on the map:

Vesuvius volcano

Volcano

Kilimanjaro

Show on the map:

Volcano

Klyuchevskaya hill

Volcano

Krakatoa

Apply to the contour map all volcanoes,

which are mentioned in the text of the textbook, Vulcan - the fire-breathing mountain. Usually volcanoes have the form of a regular cone with gentle slopes at the bottom and steep walls at the top. At the top of the volcano is a large depression with steep walls - it's a crater.
The hot substance hidden from us by the solid crust of the earth, on the boundaries of the plates, can rise high to the surface and become liquid, transformed into magma. Its temperature is so high that the rock melts and opens the magma to the surface. In the form of hot thick foam, magma rises higher until it begins to pour over the edge of the crater.
Gradually, water vapor and gases leave the magma, it becomes denser and elm-

The structure of the volcano

On the roads there are more than 100 webcams and current information about temperature and wind. There you can also learn about winter barriers. In the highlands driving is allowed only on the slopes. Cutting off slopes destroys nature steadily and takes many years to recover. If you are caught, you should expect a severe punishment. The police have their own helicopter squadrons to stop this evil.

The network of gas stations in Iceland is relatively dense, but you need to say goodbye to the idea that the gas station works in Germany. Basically you will find one pump with gasoline and diesel without any settlements within a radius of 50 km to 100 km, standing alone in the area. Usually, "pay for the pump." The usual ATM card in Austria, which is accepted by all ATMs in Iceland, is not accepted by the fuel terminal!

and then it is called lava. Lava is molten stones. The temperature of the lava is about 1000 ° C. A regular-shaped volcano is formed from frozen lava flows. The speed of the flow of lava depends on its density and eruption conditions. Sometimes it flows slowly, so that a person can walk away from the stream, sometimes the lava flow sweeps at a speed of more than 100 km / h.
If the volcano is erupted every few years or more often, it is called acting. Many active volcanoes are located on the peninsula of Kamchatka. Some volcanoes acted in the distant past, and for a long time lye had not been poured from yeh. These are extinct volcanoes. They are in the Crimea, Transbaikalia and other areas.

Therefore, it is advisable to use the following strategy of the tank. Empty the tank halfway. From Reykjavik there are connections with Akureyri, Hofn, Izarfjordur and other places. It should be noted that especially in the eastern part of Iceland bus connections exist only in the summer season. And in low season, these compounds can be depleted. If you are traveling at this time, you must plan your trip, there are no alternatives for many routes. And the fact that Icelanders, of course, did not invent, is a link. Further travel to the next destination is possible only the next day.

Some volcanoes are in the ocean, not on land. Many islands were formed solely due to volcanic activity. Volcanoes and earthquake zones are located in certain parts of the planet, that is, along the boundaries of lithospheric plates - where the most violent processes occur in the earth's crust.
The high temperature of volcanoes causes hot springs and geysers in the volcanic areas - hot fountains - of natural origin. The

Structure diagram of the geyser 26

With an overnight stay at intermediate stations, you should expect. Two bus tickets are interesting for tourists. This allows you to make a circular trip with the same number of breaks on the ring road, as well as many long breaks. Here you can pay only in cash and no changes. The regularity and distribution of bus connections correspond to a city of this size.

During the day, the lines are delivered at 30- or 60-minute intervals at about 20-30, in the evening to 23 hours. So far there is no railway in Iceland. Hitchhiking is very good on the ring road. Iceland is safe, and people are friendly. Especially in rural areas, drivers often come to you if you do not want to ride. If you want to go to secluded areas, you should have enough time and equipment to spend the night, if necessary. Especially in summer many cars travel with their luggage.

from time to time the geyser throws a jet of hot water and steam into the air. The water vapor temperature sometimes reaches 250 ° C. In some geysers the water hardly moves. The record distance to which the geyser emits hot water is more than 80 meters.
Geysers are formed wherever the hot magma comes close enough to the surface. In addition to Kamchatka, the geysers of Iceland are world famous. There, there is enough hot water to heat the capital of this country - the city of Reykjavik. Geysers are found in New Zealand, America, Japan and China.

Iceland speaks of Icelandic. English and Scandinavian are widely spoken in English for the reason that Icelandic television has many original English series or films with Icelandic subtitles. German language is less solved. It does not hurt to get the most basic phrases. Attention: the pronunciation of Icelandic words is often significantly different than expected.

Example: in the southeast is the place of Höfn, which is pronounced about Höpn, and Höfn means in Icelandic til-hafnar, which is pronounced before Hapnar, which brings, if a person is not trained and does not know the language well enough, Spelling on a map that is always corresponds to a nominative name, whereas "Hafnar" is genitive, no longer connected.