It's hard to find anyone who has ever not asked to volcanoes.Most read books about them, breathlessly watched footage of the eruption site, while admiring the power and splendor of the elements and rejoicing with them that is not happening.Volcanoes - is something that does not leave anyone indifferent.So what is it?
structure volcano
Volcanoes - a special geological formation resulting from the rise from the depths of hot mantle material and release it to the surface.Magma rises through cracks and fissures in the earth's crust.Where it breaks out, and active volcanoes are formed.This occurs at the boundaries of tectonic plates, where because of their razdvizheniya or collision faults occur.And they themselves are involved in the movement of the plate when moving the mantle.
most often take the form of conical volcanoes mountains or hills.In their structure clearly distinguished crater - the channel through which the magma rises, and the crater - indentation on the top, which takes place through the outpouring of lava.Himself volcanic cone is composed of many layers of product activity: lava bombs and volcanic ash.
Since the eruption is accompanied by emission of hot gas, glowing even in the daytime, and ash, volcanoes often called "fire-breathing mountains."In ancient times they were considered the gateway to the underworld.And the name they received in honor of the Roman god Vulcan.It was believed that the fire and smoke flying from his underground smithy.These interesting facts about volcanoes warmed the curiosity of many different people.
Types of volcanic
existing division into active and extinct very conditional.Active volcanoes - the ones that erupted in the memory of mankind.These events are preserved eyewitness.A lot of active volcanoes in the areas of modern mountain-building.This, for example, Kamchatka, the island of Iceland, East Africa, the Andes Cordillera.
extinct volcano - it's not erupted for thousands of years.In memory of the people were not kept information on their activities.But a lot of cases, when a volcano, considered long been inactive, suddenly woke up and brought a lot of troubles.The most famous of them - the famous eruption of Vesuvius in 79 AD, the famous painting Bryullov "The Last Days of Pompeii".For 5 years prior to this catastrophe at the top of his hiding insurgent gladiators Spartacus.A mountain was covered with lush vegetation.
By extinct volcanoes is Mount Elbrus - the highest peak in Russia.Her biceps peak represents two cone fused bases.
Eruption as a geological process
eruption considered process emissions on the Earth's surface is hot magmatic products in solid, liquid and gaseous state.For each of the volcano it is individual.Sometimes the eruption is quite calm, the liquid lava flow poured out and flowing down the slopes.It does not prevent the gradual release of gas, so there is no strong explosions.
This type of eruption is characteristic of Kilauea.This volcano in Hawaii is considered one of the most active in the world.Its crater with a diameter of about 4.5 km and is the largest in the world.
If the lava is thick, she occasionally clog crater.As a result of the escaping gases, finding no way out, accumulate in the crater of the volcano.When the gas pressure is very high, there is a huge explosion.He lifts up into the air large amounts of lava, which then falls to earth in the form of volcanic bombs, sand and ashes.
most famous explosive volcanoes - it is mentioned Vesuvio, Katmai in North America.
But the most powerful explosion, which led to a cooling of the world because of the volcanic cloud, through which they could hardly get through the sun's rays, occurred in 1883.Then the volcano Krakatau lost most its part.A pillar of gas and ash rose to 70 km upward.Touching a hot ocean water with magma led to the formation of a tsunami up to 30 meters. In general, the victims of the eruption were about 37 thousand people.
Modern volcanoes
believe that now there are more than 500 active volcanoes.Most of them belong to the zone of the Pacific "Ring of Fire", located along the borders of the lithospheric plate of the same name.Every year there is about 50 eruptions.In the area of their activity lives of at least half a billion people.
Volcanoes of Kamchatka
One of the most famous areas of modern volcanism is located in the Russian Far East.This is the area of the modern mountain-building relating to the Pacific Ring of Fire.Volcanoes of Kamchatka are included in the UNESCO World Heritage List.They are of great interest not only as objects of research, but also as monuments of nature.
Here is the highest active volcano in Eurasia - Klyuchevskaya Sopka.Its height is 4750 m. It is widely known for their activity and Flat Tolbachik, Mutnovsky Sopka, Gorely, Vilyuchinsky, Mountain Tooth avachinsky and others.Total Kamchatka there are 28 active volcanoes, and about five hundred extinct.But here's the interesting facts.On the volcanoes of Kamchatka knows a lot.But along with this region is known for much more rare - geysers.
It springs periodically emit fountains of boiling water and steam.Contact their activity with magma rose through cracks in the crust close to the earth's surface and underground water heating.
famous Valley of Geysers, located here, was opened in 1941, TI Ustinova.It is considered one of the wonders of nature.The area of the Valley of Geysers no more than 7 square meters.km, but there are 20 large geysers and dozens of sources with boiling water.Largest - Giant Geyser - emits a column of water and steam to a height of about 30 meters!
Which volcano above all?
Determine it's not so simple.First, the height of the active volcanoes can grow each eruption due to the rise of a new layer of rocks or decrease due to explosions that destroy the cone.
Secondly, can wake was considered extinct volcano.If it is high enough, it could push back existing leader.
Third, how to consider the height of the volcano - from the ground or from the sea level?It gives a completely different figures.After the cone having the largest absolute height, it may not be the largest in comparison with the surrounding area, and vice versa.
Currently, among the largest active volcanoes considered Lyuylyaylyako in South America.Its height is 6723 meters. But many volcanologists believe that the title of the greatest can claim Cotopaxi, located on the same continent.Let his height is less than - "only" 5897 m, but the last eruption, he had in 1942, and at Lyuylyaylyako - already in 1877
also the highest volcano in the world can be regarded as Hawaiian Mauna Loa.Although its altitude of 4169 m, less than half its true value.Cone Mauna Loa begins from the ocean floor and rises more than 9 km.That is the height from the base to the top of Chomolungma exceeds the size!
Mud volcanoes
Has anyone heard anything about the Valley of the Volcanoes in the Crimea?It is very difficult to imagine this peninsula enveloped in smoke, volcanic and beaches - suffused with red-hot lava.But you should not worry, because we are talking about mud volcanoes.
This is not an uncommon phenomenon in nature.Mud volcanoes - is the similarity of these, but they do not emit lava, and the streams of liquid and semi-liquid mud.The reason is the accumulation of eruptions in underground cavities and crevices of large quantities of gases, mostly hydrocarbons.The gas pressure drives the volcano, a tall pillar rises dirt sometimes for several tens of meters, and the ignition of the gas and explosions give eruption quite menacing look.
process can last for several days, accompanied by a local earthquake, subterranean roar.The result is a low cone of frozen mud.
areas of mud volcanism
In Crimea there are volcanoes on the Kerch Peninsula.The most famous of them - Dzhau Tepe, startled by a great locals eruption of his short (only 14 minutes) in 1914.Post mud dumped on the 60 m up.The length of the mud flow reached 500 m and a width of more than 100 m. However, such large eruption is rather an exception.
action areas of mud volcanoes often coincide with locations of oil and gas.In Russia, they are found on the Taman Peninsula, Sakhalin.From neighboring countries "rich" of Azerbaijan.
In 2007, on the island of Java volcano intensified, flooding her with mud vast territory, including many buildings.According to the local population, it happened because of the drilling of the well, to disturb deep layers of rocks.
Interesting facts about volcanoes
Edinburgh Castle in Scotland, built on top of an extinct volcano.A majority of Scots do not even know about it.
turns out, volcanoes can be actors!In the movie "The Last Samurai" in the role of the sacred mountain of Fujiyama Japanese made Taranaki, considered the most beautiful in New Zealand.The fact that the neighborhood of Mount Fuji, with its urban landscape not suitable for shooting pictures of the events of the late 19th century.
general New Zealand volcanoes do not have to complain about the lack of attention of filmmakers.After Ruapehu and Tongariro became known largely due to the film "The Lord of the Rings", which depicted the Mount Doom, in a flame which was created and subsequently there destroy the One Ring.Lonely mountain in Erebor in the film "The Hobbit" - it is also one of the local volcanoes.
A Kamchatka geysers and waterfalls become the backdrop for the filming of "Sannikov Land."
eruption of Mount St. Helens (United States) in 1980, considered the most powerful of the entire 20th century.The explosion, in its capacity of 500 bombs dropped on Hiroshima, ash fell in four states.
Icelandic volcano Eyyafyadlayokudl famously emissions of ash and smoke plunged into the chaos of European air traffic in spring 2010.And his name stumped hundreds of radio and television broadcasters.
Philippine volcano Pinatubo erupted last time in 1991.At the same time it destroyed two US military bases.But after 20 years, Mount Pinatubo crater filled with rainwater, creating a surprisingly beautiful lake, volcano slopes overgrown with tropical vegetation.This made it possible to travel agencies to organize a holiday with a swim in a volcanic lake.
The eruption often formed interesting rocks.For example, the easiest stone - pumice.Numerous air bubbles make it lighter than water.Or occur in Hawaii, "Pele's hair."They are long, thin strands of rock.Many buildings in Yerevan, Armenia built of pink tuff, which gives the city a unique flavor.
Volcanoes - a terrible and magnificent phenomenon.Interest in them is caused by fear and curiosity and a thirst for new knowledge.It's no wonder they are called the windows to the underworld.But a purely utilitarian interests.For example, volcanic soil is very fertile, and that makes people for centuries to settle near them, despite the danger.
