The famous volcanic eruption in history, scientists measure the intensity of volcanic eruption by the amount of substances discharged into the atmosphere.

According to this measurement method, the largest volcanic eruptions include (in descending order of intensity): the eruption of Yellowstone National Public Volcano in the United States, which occurred around 600,000 BC; The eruption of Doba volcano in Indonesia took place around 7 BC. Forty thousand years; In addition, Indonesia's Tambora volcano 18 15 erupted; BC 1470, the Greek volcano Saint Dorigny erupted; 1783 volcanic eruption in Iceland (this is also the largest lava eruption in history); And 1883 the eruption of Krakato volcano in Indonesia.

The volcanic eruption in Yellowstone National Park is difficult to measure: the crater area left by the volcano (located in Wyoming, USA today) reached 30 x 45 miles (48 x 72 kilometers), and the total amount of material released into the atmosphere was about 65,438+0,000 cubic kilometers. Intuitively, the second-ranked Doba volcano erupts 110, which is10,000 cubic kilometers.

The total amount of material erupted by Tambora volcano is 10 times that of Doba volcano, about 100 cubic kilometers. All other volcanoes release about 10 cubic kilometers of dust into the atmosphere.

1980 in may 18, the San hellens volcano erupted in the southwest of Washington, USA. It is also considered to be a famous volcanic eruption in history, and it is also the largest volcanic eruption among the 48 States connected with the United States in modern history.

The mass released by the eruption of Mount St. hellens is relatively small, only 1 cubic kilometer, but the destructive power after eruption is great. Most areas were covered by volcanic ash, and a large area of forest was destroyed. The north fork tributary of the Turt River is full of volcanic ash and other pyroclastic rocks, reaching a depth of 600 feet (183 meters).

The volcanic eruption killed 57 people.

What are the records of the most detailed volcanic eruption in history? At 5: 00 a.m. on April 1979, La Sufi Lier volcano erupted on Saint Vincent Island in the Caribbean! Five hours before the volcano erupted, local officials were informed; 14, a special working group composed of local and American scientists began to closely monitor the volcano; 17, the volcano erupted violently. Shoot, record and analyze the explosion site from satellites, planes, ships and the ground, so as to obtain complete seismic data, ground visual observation and air observation data.

Such a detailed and complete volcanic eruption record is rare in history. It is reported that since 197 1, the relevant departments have predicted that the volcano will have new trends according to a series of signs.

At 20 o'clock on April 1979, scientists saw the precursor of this eruption. The whole process of this eruption was recorded in the air by the infrared device of the geosynchronous satellite SMSI of the National Oceanic and Atmospheric Administration of the United States, and the photo film of the volcano was printed immediately.

What is the biggest volcanic eruption in history? World culture,No. 1985, 05, the largest volcanic eruption in history, Qiao Footwork Abstract: santorini Island is becoming more and more attractive, because there was an important ancient country here 3500 years ago, which suddenly disappeared without a trace when Minoan culture reached its brilliant peak. Only recently, through the joint investigation of archaeologists and experts from other disciplines, did I know that it was destroyed by the largest volcanic eruption in history. This island is located in the Aegean Sea in southern Greece, not far from Cyprus. The island is covered with thick sulfide. The steep mountain wall surrounds a lake with a diameter of about15km and a depth of 250m. This is an unimaginable force when a volcano erupts. It was formed after most of the original island was lifted into the air. There are many places around the lake that keep spewing hot air. In the middle of the lake, because of the hot keywords: volcanic eruption, archaeologists in Cypriot history, Crete cultural development, sulfide experts, volcanic activity, Aegean text snapshot: santorini Island is becoming more and more attractive because there was an important ancient country here 3500 years ago. When Minos (1) culture reached its brilliant peak, it suddenly disappeared without a trace. Until recently, after a joint investigation by archaeologists and other experts, it was discovered that it was destroyed by the largest volcanic eruption in history. The island is located in the Aegean Sea in southern Greece.

In 79 AD, Mount Vesuvius in 3360, lava and volcanic ash buried Pompeii and nearby towns, leaving many corpse fossils.

163 1 Italy Vesuvius 3500 years later, mudslides, earthquakes and tsunamis killed thousands of people. 1669 lava from mount Etna in Italy flooded nearby towns, killing about 20,000 people.

1783 the lakilaki 9350 in Iceland lasted for eight months and killed a quarter of the population. Mainly starved to death.

1792 The volcano in Yunxian, Kyushu, Japan 14300 collapsed, causing a tsunami. 18 15 The Indonesian Taborro volcano Tambora 92000 continuously spewed volcanic ash, which can fill the harbor as high as150m, making Fiona Fang 500km dark for three days, with the power equivalent to 200,000 atomic bombs, causing cyclones and tsunamis.

Mainly starved to death. 1882 Garunggung4011High temperature airflow and debris flow 1883 Krakatoa, Indonesia 364 17, the most violent eruption, the bell was heard nearly 5,000 miles away, causing a huge wave more than 40 meters high and drowning 3.

1902 Mt. Pelee 29025, located in the Caribbean, spewed high-temperature airflow, which first dispersed the air and then burned the sea surface, killing about 30,000 people. 19 12 The Katmai volcano in Gadermann, Alaska, spewed15km of lava, the largest eruption in North America.

(There is not much population here)1919kelut510 Debris Flow 1943 Parikutin of Parikutin Volcano in Mexico suddenly rose 40 meters from the ground overnight, rose to 460 meters one year later and stopped nine years later. 1980 San hellens 6 1, Mount San hellens, USA, the temperature rose to 800℃, the range of 130 km was dark, and the volcano sank 400 meters.

1982 El Chichon 2000 volcanic ash from Mexico's Chinchonale volcano rose to an altitude of 20,000 meters, forming a volcanic ash cloud with a thickness of 3,000 meters. 1985 Nevada Del Ruiz, Colombia, 25,000 times of lava melting, 10 meters thick debris flow flooded urban and rural areas at high speed, killing more than 20,000 people.

Major events of volcanic eruption in history have caused serious air pollution, and plants cannot grow where lava flows.

You can see Mount St. hellens in the United States: Mount St. hellens is an active volcano in the northwestern United States. Located in the northern part of the Cascade Mountains in Washington.

Southwest is 72 kilometers from Portland. It is 2950 meters above sea level.

Originally a dormant volcano, it was silent for 123 years and revived on127 March 1980. 1After three major eruptions on March 27th, May 28th and 25th, 1980, the height of the volcano dropped to 2550m, and the top of the volcano was cut off by 1/3, forming a crater with a length of 3km, a width of 1.5m and a depth of 125m, which spewed a lot.

A large amount of water vapor in the updraft condenses at high altitude to form heavy rain, which washes away volcanic ash to form mud flow and pours down the mountain, seriously damaging agriculture and forestry in Washington and Oregon. The nearby area of 390 square kilometers became barren and more than 60 people died. This is one of the largest volcanic eruptions in American history and has been active since its resurrection [1]. After 1986, it was relatively calm.

Now the relatively calm 18 years have passed. In June 2004, 10 years, a huge rumble sounded again, and a dense earthquake broke out again in St. Helen, forming a new stone mound in the crater. Researchers reported at a meeting of the American Geophysical Association on February 15 that the lava dome is now "longer" than its old neighbor, and the growth rate is amazing, expanding by 5 cubic meters per second, with no signs of slowing down at all.

But what shocked scientists in particular was the strange shape of the dome. According to Dan Dzurisin, a volcanologist at the Cascade Volcano Observatory of the US Geological Survey (USGS) in Vancouver, Washington, the new lava dome of Mount St. hellens has been extended to look like "the keel of a capsized ship".

He said: "No one predicted in advance that it would become so special." John Pallister, another volcanologist of the US Geological Survey, said that some lava domes even "grow" vertically due to thick magma.

He once flew into a crater by helicopter, where he spent five minutes collecting fresh rock samples. It is found that in the crater with uneven edges, the lava with the temperature as high as 775℃ churns endlessly, which is a "vibrant" scene.

John Pallister, a volcanologist at the US Geological Survey, said that if the dome continues to rise, this fragile "building" may collapse immediately and magma exposed to the air will erupt. "What we are most worried about is volcanic ash, which may rise from the crater to tens of thousands of feet," Gardner said. "That will threaten nearby planes."

Another threat is that these lava will melt ice and snow, leading to mudslides. He warned that the dam in the valley under the volcano might provide protection for nearby towns.

Steve Malone, a seismologist at the University of Washington in Seattle, said that although the collapse will not happen immediately, scientists have closely monitored moderate earthquakes because they may break the peak of the lava dome. He said that at present, small earthquakes with magnitude below 1.5 occur every minute, but this force is far from enough to cause rock sliding [2].

(Translated by Liu Yingnan from Science Now, 65438+February 15) The special climatic environment of the two eruptions of Mount St. hellens is worth studying. 1September 1979 to1June 1980, a weak El Nino event broke out all over the world, and a weak La Nina event occurred in 198 1 year.

The El Nino year of 15 determined by the first climate newsletter 1998 of the National Climate Center is 195 1, 1953, 1957, 1963,/kloc. 1982, 1986, 199 1, 1993, 1994, 1997,1kloc. 1973,1975,1978,198,1984,1988 [3].

198 1 year, the Yellow River and the Yangtze River flooded. It is worth noting that droughts occurred continuously in northern China from 2000 to 2004, and a weak El Ni? o event occurred in the world at the end of 2004.

The eruption of Mount St. hellens is the result of the seesaw movement of the crust in the eastern and western Pacific caused by El Ni? o events [6], which increases the possibility of La Ni? a events and floods in China. We forecast the trend of drought and flood in China and pay close attention to the arrival of La Nina in 2005 or 2007 [6- 10].

1976, la madre entered the warm phase, and in 2000, la madre entered the cold phase. The situation is just the opposite. Four years later (1980 and 2004), El Ni? o event, San hellens volcano eruption and La Ni? a event occurred one after another (predict La Ni? a event in 2005).

The difference is that the cold weather in la madre will aggravate La Nina phenomenon, and people must be fully prepared [6-8]. On June 5438+February 65438+July 2004, Sigma, a Swiss reinsurance company, released a report on the impact of the global disaster on the insurance industry in 2004.

According to the report, according to the agency's preliminary estimate, the number of victims caused by natural and man-made disasters in the world will exceed 2 1 000 in the coming year. The global economic losses caused by disasters total about 654.38+005 billion dollars, of which about 42 billion dollars need to be borne by global property insurance companies, 95% of which come from natural disasters.

The eruption of Mount St. hellens in the United States once again sounded the alarm of natural disasters! .

What are the deadliest volcanic eruptions in history? 1865438+On April 5, 2005, Mount Tambora in Indonesia erupted, killing 92,000 people and becoming the deadliest volcanic eruption.

At the end of August 1883, another volcano erupted in Krakato, Indonesia, killing 36,000 people. 1902 On August 30th, Mount Pere in French Martinique, West Indies erupted, killing at least 29,000 people.

The last deadly volcanic eruption occurred in Nevado del Ruiz, Colombia, in June 1985+065438+ 10/3, which killed 23,000 people. 1783, Iceland's Laki volcano erupted.

But judging from the death toll, it may not be among the "deadliest" volcanoes, but the death toll is really amazing: 20% of Icelanders died. Due to population growth, more and more people live near volcanoes-active volcanoes and dormant volcanoes.

As a result, the number of deaths related to volcanoes has increased: during the period of 1600- 1900, it is estimated that an average of 3 15 people die from volcanic eruptions every year. Since the beginning of the 20th century, this number has increased to 845.

According to the history of the volcano, the process before the volcano erupts from the surface can be scientifically divided into three stages: (), () and (): the stage of magma formation and initial rise, the stage of magma sac and the stage of magma sac leaving the surface.

According to activity, it is divided into 1. An active volcano refers to a volcano that is still active or erupts periodically in modern times. This Mount Merapi is in its heyday of activity.

For example, since this century, Mount Merapi on Zhaotu Island has erupted every two or three years on average. The recent volcanic activity in China is most famous in Qixing Mountain, the main peak of Datun Volcano Group on the island of Taiwan Province Province. On the mainland, only six years ago, the Caldarcy Volcano Group in Yutian, the western section of Kunlun Mountain in Xinjiang, recorded volcanic eruption.

The volcanic eruption formed a flat-topped volcanic cone. 2. An extinct volcano refers to a volcano that erupted in prehistoric times but has never been active in history.

This volcano has lost its ability to move. Some volcanoes remain intact, while others have weathered and eroded, leaving only incomplete volcanic remains. There are 99 isolated volcanic cones in the area of about 123 square kilometers in Fiona Fang, among which the height of the volcanic cone of Langwoshan is nearly 1900 meters.

3. Dormant volcano refers to a volcano that has erupted in history but has been in a relatively static state for a long time. The well-preserved cone of this kind of volcano still has volcanic activity ability, or it cannot be concluded that it has lost its volcanic activity ability.

Tianchi Lake in Changbai Mountain, China, for example, broke out twice at 1327 and 1658, before which there were many active activities. Although there is no eruption activity at present, some unfathomable blowholes on the hillside keep spewing high-temperature gas, indicating that the volcano is currently in a dormant state.

It should be noted that there are no strict boundaries between these three types of volcanoes. Dormant volcanoes can be resurrected, and dead volcanoes can also be "resurrected", and they are not static.

In the past, Mount Vesuvius was always considered as an extinct volcano. At the foot of the volcano, many towns and vineyards were built on the hillside of the volcano. However, in 79 AD, Vesuvius erupted suddenly, and the high-temperature volcanic eruption in Attack and Capture created two unsuspecting ancient cities, Pompeii and Heragonom. Cities and residents were destroyed and killed.

The most famous example of volcanic eruption is that Vesuvius directly destroyed a city, Pompeii, and the death toll seems to be 200,000.

Vesuvius was first formed in the late Pleistocene in geological history, probably less than 200,000 years ago. Although it is a relatively young volcano, it has been dormant for centuries. In 79 AD, the cities of Pompeii and Stabia were buried by volcanic ash and volcanic rubble, and the city of Herculaneum was also buried by mudslides. The writer Pliny Junior lives in a place west of Naples. He gave a wonderful description of the disaster in two letters to the historian Tacitus. In 79 AD? During 163 1 year, many eruptions were reported. The confirmed eruptions occurred in 2003, 472,512,787,968,991999, 1007 and 1036. Among them, the eruption in May12 was serious, and King Theodoric exempted the residents at the foot of Mount Vesuvius from taxes.