"Shalan. ”

Ye Wuji unexpectedly looked at the sand storm flying from the opposite pirate ship, he really didn't expect to meet the sand crocodile here, Klockdahl, and the Krokdal with a bounty of 81 million.

This sand crocodile, when he saw the warship that Ye Wuji was riding, didn't say anything, and directly came to a huge sand storm, you can imagine what kind of treatment it will be if Ye Wuji's warship is caught in the sand storm.

"Arashi. Seeing that the sandstorm was about to involve the warship, and the other navies of the warship were panicked, Ye Wuji jumped into the air with a little foot, and a powerful slash came from his right foot, cutting the sandstorm in two.

"Hey, Navy Elite. With a cigar in his mouth, Klocodahl, who was ready to look at the warship on the opposite side and disintegrate under his attack, was shocked when he saw this scene.

"Why hasn't this guy entered the new world yet. "Night Wuji is very surprised that Klockdahl is here, it has been two years since Roger's death, and two years have made many pirates begin to become famous in this sea.

Among them, Doflamingo, Moonlight Moria, and Klockdahl were the first to be famous, and when he was in the training camp, he knew from the news inside the navy that the navy was afraid of the three pirate groups.

"Klockdahl, what's wrong, you've been kicked out of the New World. As the two ships approached, Ye Wuji immediately recognized Klockdahl standing on the bow of the opposite pirate ship, holding a huge cigar and a black coat draped behind him.

Judging by the time, Klockdahl should have entered the New World by now, after all, there are not many people as unlucky as Doflamingo.

Doflamingo, the future Seven Martial Seas, is now fleeing all over the world, pursued by cranes and peach rabbits, Doflamingo has escaped from the new world and entered the North Sea.

It is worthy of the Seven Martial Seas in the future, and there is a way to escape from the new world through the windless belt.

"Look for death. Ye Wuji's words seemed to be talking about Klockdahl's sore spot, and Klockdahl's face immediately changed, and he waved his right hand, "Sand Blade." ”

A huge sand blade formed by sand and about dozens of meters long appeared in front of him, and then shot towards Ye Wuji.

"Looks like I'm right. As Ye Wuji spoke, with a wave of his right hand, a one-meter-long half-moon-shaped qi blade flew towards the sand blade, and after shattering the sand blade, it continued to fly towards Klokdal.

Syllable.

Klockdahl reached forward with his right hand and shattered the blade.

The six naval styles are actually just the basics, and ordinary people will extend their skills in the foundation of the six styles.

A volcano is a raised mound or mountain formed by the accumulation of solid debris, lava flows, or dome-shaped ejecta around its vent. A volcanic eruption is a conduit from the Earth's mantle or lithosphere to the surface, where most of the material accumulates near the crater, and some is carried high by the atmosphere and disperses to hundreds or more

Causes of volcanoes

Thousands of kilometers away.

The formation of volcanoes is a series of physicochemical processes. The main thing is that there is a large amount of radioactive material present in the interior of the earth, which decays in its natural state and produces a large amount of heat. This heat cannot be dissipated to the ground, and the temperature continues to rise until the rock melts, forming a state of hot melting in the Earth's interior. Once this magma breaks through the earth's crust and erupts out of the ground, volcanoes are formed.

Some people believe that volcanoes are caused by the melting of rocks due to pressure, and that after magma erupts from the ground, the temperature cannot be so high due to the rapid decrease in pressure, but should be at or below normal temperature. If the temperature rises due to pressure, then when the pressure does not increase, the temperature will not rise again, that is, at the beginning of the formation of the earth, the temperature will not rise again.

We can do such an experiment, the refrigerant used in the refrigerator is loaded into a well-sealed piston, the piston is compressed and the pressure is kept unchanged, the temperature of the refrigerant will increase first, and after the pressure is unchanged, the temperature will remain the same or gradually decrease. Even if the refrigerant is suddenly depressurized to normal pressure at the highest temperature, the temperature is unlikely to be much higher than the normal temperature. It is even less likely that the rock will remain melted and ejected from the ground.

From the perspective of thermodynamic theory, the whole process is analyzed: during compression, the temperature increases when the refrigerant is worked on the outside world, and when the pressure is reduced, the temperature will inevitably decrease.

Therefore, volcanoes are supposed to be formed by melting rocks from the heat generated by the decay of radioactive materials.

The source of magma

Magma is divided into primary magma and regenerated magma.

Primary magma is formed from molten material trapped by the Earth's core. The Earth's core traps molten material and some other materials to form a huge thick molten layer. The composition of these substances is uneven. The primary magma solidified to form the most primitive earth's crust.

The various types of intrusive rocks seen today, such as ultramafic rocks, mafic rocks, neutral rocks, acidic rocks and alkaline rocks, as well as various types of magma erupted by volcanoes, are all regenerated magma, but the source depth, channel, material composition and degree of differentiation are different.

Regenerated magma includes magma mutated from primary magma and relava magma.

Today's liquid layer is made up of regenerated magma formed by mutation of primary magma – formed by changes in temperature, composition, and state of matter.

The dynamics of magma migration

There are two main driving forces for magma to move from the depths of the earth to the earth's crust to form intrusive rocks or erupt to the surface to form volcanoes:

First, because the specific gravity of the inner sphere of the Earth is greater than that of the liquid layer and the outer sphere, the inner sphere always deviates in the opposite direction of gravity when revolving around the sun, and the inner sphere is not at the center of the Earth. The formation of an inner sphere squeezing force on the liquid layer from the inside to the outside, causing magma and other gaseous and liquid materials to move from the inside of the earth outward or erupt to the surface.

Second, magma crystallization or other physicochemical reactions occur, producing some water, gas and other substances, forming an expansion and extrusion force, causing magma and other gas-liquid substances to move outward from the earth's interior or erupt to the surface.

structure

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It consists of a crater, a magma channel, and a volcanic cone [1].

There are about 2,000 known "extinct volcanoes" on Earth, and a total of 523 "active volcanoes" have been discovered, of which 455 are on land and 68 are undersea volcanoes. Volcanoes are unevenly distributed on Earth, and they all occur in fault zones in the earth's crust. Worldwide, volcanoes are mainly concentrated in the Pacific Rim and Indonesia north through Myanmar, the Himalayas, Central Asia, West Asia to the Mediterranean Sea, and the present-day Earth

Volcanic eruptions

The vast majority of active volcanoes are located in these two zones.

Volcanoes have a long history of occurrence. Some volcanoes have erupted before human history, but are no longer active, such volcanoes are called "extinct volcanoes"; volcanoes that have erupted in history, but have been in a relatively stationary state for a long time, such volcanoes have preserved intact volcanic cone morphology, still have volcanic activity, or it is not yet possible to conclude that they have lost volcanic activity, people call them "dormant volcanoes"; volcanoes that have erupted from time to time in human history are called "active volcanoes".

Between 100 and 150 kilometers below the earth's crust, there is a "liquid zone" (asthenosphere) in which molten silicates containing gaseous volatiles, known as magma, are present at high temperatures and pressures. Once it washes out of the surface of the earth from a weak part of the earth's crust, it forms a volcano.

Volcanic activity can eject a variety of materials, among the solid materials that are ejected, there are generally rocks, debris and volcanic ash that have been blown up; among the liquid materials that are ejected, there are generally lava flows, water, various aqueous solutions, and mud flows mixed with water, detritus and volcanic ash; and in the ejected gaseous substances, there are generally water vapor and oxides such as carbon, hydrogen, nitrogen, fluorine, sulfur, etc. In addition, volcanic activities often eject visible or invisible light, electricity, magnetism, sound, and radioactive substances, which can sometimes kill people, or cause electrical and instrument failures, and cause planes and ships to crash.

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Volcanic eruptions

At a depth of about 32 kilometers above the surface, there is a large amount of hot liquid, which is hot enough to melt most of the rock.

The rock expands when it melts, requiring more space. In some parts of the world, mountains are rising. The pressure is decreasing beneath these rising mountains, and a reservoir of lava (also known as "magma") may form underneath these mountains.

This substance rises along the cracks caused by the uplift. When the pressure in the lava reservoir is greater than the pressure on the rock roof above it, it bursts outward into a volcano.

During an eruption, a red-hot gas, liquid, or solid substance suddenly emerges. These materials accumulate around the opening, forming a cone-shaped mountain. A "crater" is a depression at the top of a volcanic cone, with openings leading to the surface. The cone-shaped mountain is a product of volcanic formation. The material emitted by the volcano is mainly gas, but large quantities of volcanic rock and solid material such as slag and ash are also ejected. Actually, volcanic rock is magma that has been erupted by a volcano, and when the magma rises to a height close to the earth's surface, its temperature and pressure begin to drop, physical and chemical changes occur, and the magma becomes volcanic rock.

formation

The formation of volcanoes involves a series of physicochemical processes. When the volume fraction of the bubble exceeds 75%, the bubble confined in the liquid will be quickly released, resulting in an explosive eruption, and the magma viscosity will drop to a very low level after the gas is released, and the flow will turn into turbulent nature. If the magma has a low viscosity or low volatile, there will be only a quiet overflow. The difference in physicochemical changes, from partial melting to eruption, has led to a wide variety of volcanic activity.

distribution

Since the establishment of plate tectonics theory, many scholars have established a global volcanic model based on plate theory, believing that most volcanoes are distributed on plate boundaries, and a few volcanoes are distributed in plates, and the former constitutes four major volcanic belts, namely the Pacific Rim Volcanic Belt, the Mid-Ocean Ridge Volcanic Belt, the East African Rift Valley Volcanic Belt and the Alpine-Himalayan Volcanic Belt. The significance of the plate theory in volcanic research lies in the fact that it can connect many seemingly isolated phenomena into an organic whole, but the model of volcanic activity established by this theory is not very perfect, such as why there are no volcanic belts around the Atlantic, and the intraplate volcano is not on the plate boundary, and the explanation of its origin with mantle plumes does not seem to be sufficient. Recently, another scholar (Li Hongye, 1993) put forward the theory of bipolar extrusion, which unveiled the mystery of the earth's development, and he believed that under the action of bipolar extrusion, the earth's equatorial axis expands to form meridional tension rift and zonal extrusion, and the global volcanoes are mainly distributed in the meridional and zonal tectonic belts. The following figure shows the global distribution map of volcanoes and strong earthquakes, the red in the figure is the Holocene volcanoes, the data is taken from the Smithsonian Institute, and the white is a strong earthquake of magnitude 7 or higher, drawn according to the catalog of the China Earthquake Network.

1. The Pacific Rim Volcanic Belt

The Pacific Rim Volcanic Belt (also known as the Pacific Rim Belt, Pacific Rim Seismic Zone, or Ring of Fire) stretches from the Andes Mountains in South America to the Rocky Mountains (Cordillera Mountains) in western North America and turns to the northwest

Pacific Rim Volcanic Belt

The Aleutian Islands and Kamchatka Peninsula extend to the southwest are the Kuril Islands, the Japanese archipelago, the Ryukyu Islands, the Taiwan Islands, the Philippine Islands and the Indonesian Islands, with a total length of more than 40,000 kilometers and a circular tectonic system that opens to the south. The Pacific Rim Volcanic Belt, also known as the Pacific Rim Fire Ring, has 512 active volcanoes, including more than 30 active volcanoes in the southern section of the Andes Mountains of the Cordillera Mountains in South America, 16 active volcanoes in the northern section, and the middle section of the Yuyeac volcano is 6723m above sea level, which is the highest active volcano in the world. Further north is the Caribbean Sea, along the Pacific coast are famous volcanoes such as Chiriqui, Irasu, Santa Ana and Tahumulco. There are more than 90 active volcanoes in North America, including the famous ones St. Helens, Lassen, Rainier, Shasta, Hood and Sanford. The most famous in the Aleutian Islands are the Katmai volcanoes and the Eliamna volcanoes. There is the frequently active Kryuchiv volcano in Kamchatka, which strikes the Kuril Islands and the Japanese archipelago Yamajima Island Arc, and famous volcanoes such as Mt. Asama, Mt. Iwate, Mt. Tokachi, Mt. Aso, and Mt. Mihara are active volcanoes that have erupted many times. There are many volcanic islands from the Ryukyu Islands to Taiwan Island, such as Chiwei Island, Diaoyu Island, Pengjia Island, Penghu Island, Qixingyan, Orchid Island and Huojiao Island, all of which have been formed since the Cenozoic Era. The most volcanic activity can be counted as volcanoes from the Philippines to the Indonesian archipelago, such as Krakatoa, Pinatubo, Tayun, Tambora and Pere in the Lesser Antilles, which have erupted many times in recent times.

The Pacific Rim is home to high volcanic activity, with 80% of the world's modern eruptions occurring in North America, Kamchatka, Japan, the Philippines and Indonesia. Indonesia is known as the "country of volcanoes", the southern part includes Sumatra, Java Islands composed of arc-trench system, nearly 400 volcanoes, of which 129 are active volcanoes, here only 1966-1970 five years, there are 22 volcanic eruptions, in addition to submarine volcanic eruptions also occur frequently, causing some new volcanic islands to outcrop the sea.

The volcanic rocks of the Pacific Rim Volcanic Belt are mainly the products of neutral magmatic eruptions, forming a calc-alkaline series of rocks, the most common type of volcanic rock is andesite, 150-300 kilometers away from the trench axis of the land, andesite parallel to the trench in an arc-shaped distribution, that is, the so-called "andesite line". Another characteristic is that the rocks from the trench to the land direction have obvious horizontal zonalization, and are generally distributed into rocks of the Laga series, calc-alkaline series rocks and alkaline series rocks with the increase of distance from the trench. Volcanoes here erupt in a central manner, and volcanic eruptions are of high intensity, often causing serious volcanic disasters if they occur in densely populated areas.

2. The Ocean Ridge Volcanic Belt

The mid-ocean ridge, also known as the Ocean Rift Valley, spreads around the globe in a "" shape, from the Arctic basin through Iceland to the South Atlantic, which is divided into the Atlantic crust and runs parallel to the coastline on both sides. Turning south around the southern tip of Africa, it turns to NE to meet the mid-Indian Ocean ridge. The Mid-Indian Ocean Ridge extends northward to the northern tip of the African continent and meets the East African Rift Valley. To the south around the east of Australia, and the southern end of the Pacific Ridge, the Pacific Ridge is biased to the eastern part of the Pacific, and extends to the north and enters the Arctic area, and the entire Mid-Ocean Ridge constitutes a "" shaped pattern, becoming a global ocean rift valley, with a total length of more than 80,000 kilometers. The central part of the ocean rift is mostly a raised ridge, which is 2-3 km higher than the sea plains on both sides.