There is a "liquid zone" between 100 and 150 km under the crust. In this liquid zone, there is a molten silicate substance containing gas volatiles at high temperature and high pressure, that is, magma. Once it rushes out from the weak part of the earth's crust, a volcano is formed.
There are about 2000 known "extinct volcanoes" on the earth; There are 5 1638 "active volcanoes" discovered, including 5 16 154 on land and 5,464 underwater. Volcanoes are unevenly distributed on the earth, and all appear on the fault zone in the crust. Worldwide, volcanoes are mainly concentrated around the Pacific Ocean and Indonesia, passing through Myanmar, Himalayas, Central Asia and the Mediterranean Sea to the north. Today, 99% of the active volcanoes on the earth are distributed in these two belts.
Volcano has a long history. Some volcanoes have erupted before human history, but they are not active now. Such a volcano is called an "extinct volcano"; However, some "extinct volcanoes" will suddenly erupt with the change of the earth's crust, which is called "dormant volcano"; Volcanoes that erupt from time to time in human history are called "active volcanoes".
Volcanic activity can eject a variety of substances, and among the ejected solid substances, there are generally rocks, debris and volcanic ash crushed by blasting. Among the ejected liquid substances, there are generally lava flows, water, various aqueous solutions and mud flows mixed with water, debris and volcanic ash. Among the ejected gas substances, there are usually water vapor and oxides of carbon, hydrogen, nitrogen, fluorine and sulfur. In addition, in volcanic activities, visible or invisible light, electricity, magnetism, sound and radioactive substances are often ejected, which can sometimes kill people, or make power and instruments fail, resulting in plane and ship crashes.
The intensity of volcanic eruption is related to the nature of lava. The eruption time is long or short, ranging from a few hours to thousands of years. According to volcanic activity, volcanoes can be divided into three categories: active volcanoes, extinct volcanoes and dormant volcanoes. The dormant volcano refers to the eruption recorded in human history, but its activity has not been seen since then. There are about 500 active volcanoes in the world.
Volcanic eruption will cause great losses to human beings, lives and property in a short time. This is a catastrophic natural phenomenon. However, after volcanic eruption, it can provide abundant land, heat energy, various mineral resources and tourism resources.
Many books describe the volcanic eruption in detail. For example, Biography of Heilongjiang Province describes the eruption of two volcanoes in Wudalianchi Volcano Group in Heilongjiang Province. "In the southeast of Mulgen (now Nenjiang), one day there was an underground fire, stones soared, and the sound shook the fields. The more days the fire goes out, the land becomes a pond. This is the fifty-eighth year of Kangxi. "
Volcanic types
(a) According to the classification of volcanic activity
1, active volcano
Refers to a volcano that is still active or erupts periodically in modern times. This volcano is at the peak of its activity. For example, Mount Merapi in Zhaotu Island has been erupting every two or three years since this century. 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. Volcanic eruption formed a flat-topped volcanic cone with an altitude of 100004 1m, a height of 25746 1m, a base diameter of 656655m, a top diameter of 254688524m and a crater depth of 9659885m m.
2. 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 1230 square kilometers in Fiona Fang, among which the height of the volcanic cone of Langwoshan is nearly19000m.
3. dormant volcano
Refers to a volcano that has erupted in history but has been relatively static for a long time. This kind of volcano has preserved a complete volcanic male body and still has volcanic activity ability, or it cannot be concluded that it has lost its volcanic activity ability. For example, China Baitoushan Tianchi erupted twice in 1327 and 1658, and there were many activities before that. 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 26 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.
(two) according to the type of volcanic eruption.
Volcanism is influenced by factors such as magma properties, underground magma chamber pressure, volcanic channel shape and volcanic eruption environment (land or underwater), which makes volcanic eruption have the following types.
1, fissure eruption
Magma overflows the surface along a huge crack in the earth's crust, which is called fissure eruption. There is no strong explosion phenomenon in this eruption, and the ejecta are mostly basic molten slurry, which often forms a lava platform with a wide coverage after condensation. For example, the Permian Emeishan basalt distributed in the border area of Sichuan, Yunnan and Guizhou in southwest China and the Tertiary Hannuoba basalt north of Zhangjiakou in Hebei belong to fissure eruption. Modern fissure eruption is mainly distributed in the mid-ocean ridge at the bottom of the ocean. Only Iceland can see this kind of volcanic eruption on the mainland, so it is also called Icelandic volcano.
2. Central eruption
Underground magma is ejected from the surface through a tubular volcanic passage, which is called central eruption. This is the main form of modern volcanic activity, which can be subdivided into three types:
Quiet type: when the volcano erupts, only a large amount of hot magma flows out of the crater quietly and flows slowly along the hillside, just like cooking rice soup from a rice cooker. Overflow is mainly alkaline molten slurry with high temperature, low viscosity and easy flow. Less gas, no explosion, Hawaii volcano is its representative, also known as Hawaiian type.
Explosive; When the volcano erupts, it explodes violently, and at the same time, it ejects a lot of gas and pyroclastic materials, and the molten slurry ejected is mainly medium-acid molten slurry. 1568 On June 25th, Mount Pere in the West Indies erupted, also known as the Pere type.
Intermediate type: it belongs to the transitional type between calm eruption and explosive eruption. This type is dominated by intermediate-basic lava eruption. If there is an explosion, the explosive force is not great. It can erupt smoothly for months or even years and is characterized by intermittent eruption. Take stron Boulder Volcano on the Lipari Islands near the Italian west coast as an example. The volcano erupts about every 2-3 minutes, and its flame can still be seen 669 kilometers away at night. So it is also called Stromboli style.
3. Infiltration eruption
Magma penetrates the earth's crust and overflows the surface in a large area, which is called penetrating eruption. This is an ancient way of volcanic activity, which no longer exists in modern times. Some scholars believe that the Archean crust is thin and the underground magma temperature is high, which often causes penetrating magma ejection.
Volcanic influence
The most powerful and spectacular volcanic eruptions often occur in subduction zones. The volcano here may erupt again after hundreds of years of silence, and once it erupts, its power is particularly fierce. This kind of volcanic eruption often brings disasters to mankind.
1, affecting the global climate
When a volcano erupts, a large amount of volcanic ash and gas will have a great impact on the climate. Because in this case, dark days, storms and even mud rain will bother local residents for months. Volcanic ash and gas are sprayed high into the air, and they will spread far away with the wind. These volcanic materials will block the sunlight and cause the temperature to drop. In addition, they will filter out some wavelengths of light, making the sun and the moon look like they are covered with a halo or have strange colors, especially at sunrise and sunset, which can form a strange natural landscape.
Step 2 destroy the environment
A large amount of volcanic ash ejected by volcanic eruption combined with heavy rain to form debris flow, which can destroy roads and bridges, flood nearby villages and cities and make countless people homeless. Mud formed by soil and rock fragments can flood the whole city.
Although the rocks are covered by volcanic ash clouds, when the volcano just erupted, you can still see huge rocks spewing into the air.
Step 3 rejuvenate
Volcanic eruption has a far-reaching impact on the natural landscape. Land is the most precious resource in the world, because it can breed all kinds of plants to support everything. If volcanic eruption can cover farmland with volcanic ash less than 20 cm thick, it is really a blessing for farmers, because these volcanic ash are rich in nutrition and can make the land more fertile.
After the disintegration of lava, weeds and liverworts began to appear.
Pteridophytes grow on the hillside where rope-like lava flows.
Volcanic ash enriches the surrounding land, and local grapes are harvested every year.
Volcanic eruption presents a crazy side of nature. An erupting volcano may spew a hot red lava flow, or spew a lot of volcanic ash and volcanic gas. Such natural disasters may cause thousands of casualties, but most volcanic eruptions will only cause minor damage to life and property. Volcanic eruption is a natural disaster, which can occur all over the world, but it happens frequently in some areas.
Earthquake is the rapid vibration of the earth's surface, which was also called earthquake in ancient times. Just like wind, rain, lightning, landslides and volcanic eruptions, they are natural phenomena that often occur on the earth.
It originated from a certain point underground, which is called the source. Vibration comes from the source and propagates in the earth. The closest point on the ground to the earthquake source is called the epicenter, which is the place where the vibration was first received. Ground vibration is the most intuitive and common manifestation of earthquakes. Strong earthquakes at the bottom of the sea or in coastal areas will cause huge waves, which is called tsunami. Earthquakes are extremely frequent, and there are about 5 million earthquakes every year in the world.
The structure of the ball is like an egg, which can be divided into three layers. The middle layer is the "yolk"-the core; In the middle is "egg white"-mantle; The outer layer is the "eggshell"-the shell. Earthquakes usually occur in the earth's crust. The earth is constantly rotating, and the interior of the crust is constantly changing. The resulting force led to the deformation, fracture and dislocation of the crust and strata, so an earthquake occurred. The place where an earthquake occurs underground is called the source. The place from the source vertically upward to the surface is called the epicenter. The distance from the epicenter to the source is called the focal depth. Earthquakes with a focal concentration of less than 70km are shallow earthquakes, earthquakes with a focal concentration of 70km to 300km are moderate earthquakes, and earthquakes with a focal concentration of more than 300km are deep earthquakes. The earthquake with the deepest focal depth was 1963, which occurred in the northern part of Irian Jaya province, Indonesia, with a focal depth of 786 kilometers. Earthquakes of the same size have different damage to the ground because of different focal depths. The shallower the source, the greater the damage, but the smaller the spread, and vice versa.
The distance from a place to the epicenter is called epicentral distance. Earthquakes with epicentral distance less than 1000 km are called near earthquakes, earthquakes with epicentral distance between 100- 1000 km are called near earthquakes, and earthquakes with epicentral distance greater than1000 km are called teleseisms. Among them, the farther the epicentral distance, the smaller the impact and damage.
The ground vibration caused by earthquake is a complex movement, which is the result of the joint action of longitudinal wave and shear wave. In the epicenter, longitudinal waves made the ground jump up and down. Shear waves make the ground shake horizontally. Because longitudinal waves travel faster and decay faster, while shear waves travel slower and decay slower, they are far from the epicenter, so you often can't feel the jump up and down, but you can feel the horizontal shaking.
The magnitude of the earthquake itself is expressed by magnitude, and the magnitude is determined according to the energy of elastic waves released during the earthquake. China generally uses the Richter scale. Earthquakes with magnitude less than 2.5 are usually called small earthquakes, earthquakes with magnitude 2.5-4.7 are called inductive earthquakes, and earthquakes with magnitude greater than 4.7 are called destructive earthquakes. For every magnitude difference of 1, the energy released by the earthquake is about 30 times different. For example, an earthquake of magnitude 7 is equivalent to 30 earthquakes of magnitude 6 or 900 earthquakes with magnitude difference of 0. 1, and the average difference of energy released is 1.4 times.
When a large earthquake occurs in a certain place, a series of earthquakes often occur within a period of time, the largest of which is called the main earthquake, the earthquake before the main earthquake is called the foreshock, and the earthquake after the main earthquake is called the aftershock.
Earthquakes have a certain temporal and spatial distribution law. In terms of time, earthquakes have periodic phenomena of alternating active periods and quiet periods. From a spatial point of view, the distribution of earthquakes has certain zones, called seismic zones, which are mainly concentrated in the Pacific Rim and Mediterranean-Himalayan seismic zones. The Pacific seismic belt almost concentrates more than 80% of shallow earthquakes (0 km ~ 70 km) in the world, and all moderate earthquakes (70 km ~ 300 km) and deep earthquakes release about 80% of the total energy.
The degree of ground vibration at a certain point during an earthquake is called seismic intensity. China divides the earthquake intensity into 12 degrees.
Although both magnitude and intensity can reflect the strength of an earthquake, their significance is the same. The same earthquake has only one magnitude, but the intensity varies from place to place, and the intensity value varies from place to place. For example, on1February 1990 10, an earthquake of magnitude 5. 1 occurred in Changshu-Taicang. Some people say that Suzhou is level 4 and Wuxi is level 3, which is wrong. No matter where it is, it can only be said that an earthquake of magnitude 5. 1 occurred in Changshu-Taicang, but this time, the earthquake intensities in shaxi town, Taicang, Suzhou and Wuxi were 6 degrees, 4 degrees and 3 degrees respectively.
Seismic intensity is a frequently used term. There are qualitative and quantitative standards for dividing strength. On the China Earthquake Intensity Table (see the table below), people's feelings and the degree of earthquake damage of ordinary houses are described, which can be used as the basic basis for determining the intensity.
Cause of earthquake
There are many reasons for the vibration of the earth's surface. According to the causes of earthquakes, earthquakes can be divided into the following categories:
1. Crustal earthquake
Earthquakes caused by dislocation and fracture of rock strata in deep underground are called tectonic earthquakes (Figure1-1). This kind of earthquake has the highest frequency and the greatest destructive power, accounting for more than 90% of the global earthquakes.
2. Volcanic earthquake
Earthquakes caused by volcanism, such as magmatism and gas explosion, are called volcanic earthquakes. Volcanic earthquakes can only occur in volcanic active areas, and earthquakes in volcanic active areas only account for about 7% of global earthquakes.
3. Collapse earthquake
The earthquake caused by the collapse of underground caves or the top of mines is called collapse earthquake. Such earthquakes are relatively small in scale and few in frequency. Even if it exists, it often occurs in limestone areas with dense caves or large underground mining areas.
4. Induced earthquake
Earthquakes caused by reservoir impoundment and oil field water injection are called induced earthquakes. This kind of earthquake only occurs in some specific reservoir areas or oil fields.
5. Artificial earthquake
The ground vibration caused by underground nuclear explosion and explosive blasting is called artificial earthquake. Artificial earthquakes are earthquakes caused by human activities. Such as vibration caused by industrial blasting and underground nuclear explosion; High-pressure water injection in deep wells and water storage in large reservoirs increase the pressure on the earth's crust and sometimes induce earthquakes.
The place where seismic waves are generated is called the source. The vertical projection of the source on the ground is called the epicenter. The depth from the epicenter to the source is called the focal depth. Generally, the focal depth less than 70km is called shallow earthquakes, the depth of 70-300km is called Zhongyuan earthquake, and the depth greater than 300km is called deep earthquake. Destructive earthquakes usually occur in shallow earthquakes. For example, the focal depth of the Tangshan earthquake in 1976 was 12km.
The eight most famous earthquakes in China.
Earthquake name, date, time and magnitude (milliseconds), epicenter intensity and focal depth (kilometers)
1. Xingtai earthquake in Hebei province1966.3.805: 29:14.06.8ix10.
Dongwang, Ningjin, Hebei1966.3.2216:19: 46.0 7.2x10
2. Yunnan Tonghai Earthquake1970.1.501:00: 37.07x13.
3. Sichuan Luhuo earthquake1973.2.618: 37: 08.3 7.9x17.
4. Zhaotong earthquake in Yunnan+0974.5.1103: 25:18.37.1ix14.
5. Liaoning Haicheng Earthquake1975.2.0419: 36: 06.07.3IX12.
6. Yunnan Longling Earthquake1976.5.29 20: 23:18.07.3Ix24
1976 . 5 . 29 22:00:22.5 7.4 IX 20
7. Hebei Tangshan Earthquake1976.7.28 03: 42: 53.8 7.8 Xi 22
8. Sichuan Songpan Earthquake1976.8.16 22: 06: 46.27.2Ix24
1976 . 8 . 23 1 1:30: 10.0 7.2 VIII 23
Earthquake self-help daquan
It is a better method of emergency protection to avoid nearby during an earthquake and evacuate to a safe place quickly after the earthquake. The so-called near avoidance is to make different countermeasures according to different situations.
Shock absorption of school personnel
In school, what is most needed in the earthquake is the calmness and decisiveness of school leaders and teachers. In areas with medium and long-term earthquake prediction, students should be taught about earthquakes, prevention and shock absorption in combination with teaching activities. Before the earthquake, we should arrange the route and venue for students to transfer and evacuate; After the earthquake, calmly direct the students to evacuate in an orderly manner. In a relatively solid and safe house, students who can hide under desks, beside platforms and in teaching buildings can go to small rooms supported by pipes, and students are not allowed to run around or jump off buildings.
When there is an earthquake, walk in the street to prevent electric shock.
When the earthquake occurred, the glass fragments of high-rise buildings and the concrete fragments outside the buildings, as well as advertising signs, tinplates, neon red light frames, etc. , may fall and hurt people. So when walking in the street, you'd better put your bag or soft things on your head, and you can also put your hands on your head when you are free. Try to be prepared for self-defense. To be calm, leave the telephone poles and fences quickly and run to a relatively open place to hide.
Workshop worker shock absorption
Workshop workers can hide under cars, machine tools and tall equipment, and don't panic and run around. Workers in special posts should first close the valves of flammable, explosive and toxic gases, reduce the temperature and pressure of high-temperature and high-pressure pipelines in time, and close the operation equipment. Most people can leave the work site, and a few people can stay at the site to monitor the danger at any time under the premise of safety protection, deal with possible accidents in time and prevent secondary disasters.
Emergency shock absorption of running vehicles in earthquake.
(1) The driver should slow down as soon as possible and brake gradually;
(2) Passengers (especially on the train) should firmly grasp the handle, post or seat with their hands, and pay attention to prevent luggage from falling from the luggage rack and hurting people. People facing the driving direction should put their arms on the seat cushion in front, protect their faces, lean toward the passage, and protect their heads with their hands; People with their backs to the direction of driving should protect the back of their heads with their hands, raise their knees to protect their abdomen, tighten their bodies and take a defensive posture.
Emergency shock absorption of people in buildings during earthquakes.
Once an earthquake happens, keep a clear head, judge the vibration in time, and never jump off a building in a panic. Secondly, you can hide under solid furniture, or in a corner, or you can move to a kitchen, toilet and small room with many load-bearing walls for temporary shelter. Because these places have strong binding force, especially the pipeline has good supporting force and large seismic coefficient after treatment. In a word, according to the building layout and indoor conditions, we can evaluate the situation and find safe spaces and passages to avoid and reduce casualties.
Emergency shock absorption in the store during earthquake
The department store kept calm when it was hit by an earthquake. Due to the panic of people and the falling of goods, the refuge passage may be blocked. At this time, you should hide near big pillars and big commodities (avoid commodity display cabinets), or hide in an unobstructed passage, and then bend down and wait for the earthquake to subside. In the upstairs position, in principle, it is best to transfer to the ground floor. However, stairs are often the weak parts of buildings in earthquake resistance. Therefore, we must seize the opportunity to escape. Attendants should organize the masses to avoid nearby and evacuate safely after the earthquake.
Self-help after the earthquake
If you are buried under the ruins during the earthquake, your surroundings are dark and there is only a very small space. Don't panic, be calm, build up confidence in survival, and believe that someone will come to save you and do everything possible to protect yourself.
After an earthquake, there are often many aftershocks, and the situation may continue to deteriorate. In order to avoid new injuries, we should try our best to improve our environment. At this time, if you carry an emergency kit with you, it will play a great role in getting out of danger.
In this extremely unfavorable environment, first of all, we should protect the smooth breathing, remove the debris from the head and chest, and cover your mouth and nose with wet clothes when you smell gas and toxic gases; Avoid weak collapsed objects and other falling objects above the body; Expand the stable living space and support the ruins with bricks and sticks to prevent the environment from further deterioration after aftershocks.
Try to get out of danger. If you can't find a way out of danger, save your strength as much as possible, and beat something that can make a sound with a stone to send out a distress signal. Don't cry, don't be impatient, don't act blindly, it will consume a lot of energy and physical strength. Try to control your emotions or close your eyes and wait for rescuers to arrive. If you are injured, try to dress it to avoid excessive bleeding.
Sustain life. If you have been buried under the rubble for a long time, rescuers have not arrived, or you have not heard the distress signal, you must find ways to maintain your life. Water and food in the earthquake-proof bag must be stored, and ways should be found to find food and drinking water. Your urine can also quench your thirst if necessary.
Mutual rescue after earthquake
After the earthquake, it is impossible for the external disaster relief team to rush to the disaster relief site immediately. In this case, in order to let more people buried under the rubble get precious lives, people in disaster areas actively participate in mutual rescue, which is the most timely and effective way to reduce casualties, and also embodies the lofty virtue of "saving people from danger".
Timely rescue time, the greater the hope of being rescued. According to relevant data, the survival rate of the rescued personnel within 20 minutes after the earthquake is over 98%, and the survival rate of the rescued personnel within 1 hour after the earthquake is reduced to 63%. Among those who could not be rescued within two hours after the earthquake, the number of people who died of suffocation accounted for 58% of the deaths. They were not killed by the collapse of buildings in the earthquake, but died of ventricular arrest. If they can be rescued in time, they can completely get life. Hundreds of thousands of people were buried in the ruins in Tangshan earthquake, and most of them were reborn through self-help and mutual help. The mutual aid action of the people in the disaster area has played an irreplaceable role in the whole earthquake relief.
Rescuing people quickly after the earthquake.
To save people after the earthquake, we should strive for the principles of fast time, accurate goals, proper methods and growing mutual aid teams. The specific approach is: first save the neighborhood, whether it is family, neighbors or strangers, don't go far; Save those who are saved first, so as to quickly expand the mutual rescue team; Save young adults and medical staff first, so that they can give full play to their role in disaster relief; Save "life" first, and then save "people" In Tangshan earthquake, a rural woman only showed her head to avoid suffocation, and then went to save another person, saving dozens of people in a short time.
A way to save lives
According to the actual situation of the post-earthquake environment and conditions, effective rescue methods should be adopted in order to safely rescue the buried people from the ruins.
Through understanding and searching, it is determined that there are buried people in the ruins, and then the buried position is judged, and the rescue signal is transmitted by shouting or knocking on the ruins.
During the rescue, special attention should be paid to the safety of the buried personnel. First, the tools used (such as iron bars, hoes, sticks, etc.). ) should not hurt buried personnel; Second, don't destroy the supporting conditions around the space where the buried personnel are located, causing new collapse and making the buried personnel in distress again; Third, communicate with the closed space of buried personnel as soon as possible, so that fresh air can flow to people. If the dust is too large during excavation, water should be sprayed to reduce dust to avoid suffocation of buried personnel; Fourth, if you are buried for a long time and it is difficult to rescue for a while, you can try to deliver drinking water, food and medicine to the buried people to maintain their lives.
Before the rescue operation, we should plan and step by step, and consider where to dig, where not to dig, where to use hoes and where to use sticks.
In the past, rescuers acted blindly, stepping on the roof above the buried person and crushing the buried person to death. Therefore, in the process of rescue, scientific analysis and action are needed to get good rescue effect, and blind action often causes new harm to the rescued object.
Rescue and nursing
First of all, the head of the buried person is exposed from the ruins, and the dust in the nose and mouth is removed to ensure smooth breathing. For those who are seriously injured and can't leave the burial site by themselves, try to carefully remove the buried objects on and around them, and then carry the buried people out of the ruins without forcibly dragging them.
For those who are hungry and cold, injured and suffocated, and buried for a long time, cover their eyes with dark cloth after being rescued to avoid strong light stimulation. According to the severity of the injury, the injured person shall be bandaged or sent to a medical point for emergency treatment.
Main points of shock absorption
Whether to run or hide during an earthquake, most experts in our country believe that it is a better way to avoid nearby during an earthquake and evacuate to a safe place quickly after the earthquake. Shock absorption should be chosen in a solid place indoors, under (next to) objects that can cover the body, which is easy to form a triangular space, a small place with support, and an open and safe place indoors.
The posture that the body should take:
Lie down, squat or sit down, try to curl up and lower your center of gravity.
Grab a solid object, such as a table leg.
Protect your head, neck and eyes, and cover your mouth and nose.
Avoid crowds, don't crowd around, and don't light open flames casually, because there may be flammable and explosive gases in the air.
School shock absorption
In class, under the command of the teacher, hold your head quickly, close your eyes and hide under the desk.
When you are in the playground or outdoors, you can squat down in place, protect your head with your hands, and pay attention to avoiding tall buildings or dangerous objects.
Don't go back to the classroom
Evacuation should be organized after the earthquake.
Never jump off a building! Don't stand outside the window! Don't go to the balcony
Classes should be held outdoors when necessary.
Family shock absorption
The earthquake warning time is short, and the indoor shock absorption is more real, and the triangular space formed after the collapse of indoor houses is often a relatively safe living place for people, which can be called shock absorption space. This mainly refers to the space formed by large collapsed bodies and supports.
Indoor triangular space is easy to form:
Under the edge of the kang, close to solid furniture;
Root and corner of interior wall;
Kitchen, bathroom, storage room and other small places.
Shock absorption in public places
Listen to the instructions of the field staff, don't panic, don't rush to the exit, avoid crowding, avoid crowds, and avoid being pushed to the wall or fence.
In theatres, gymnasiums, etc:
Squat down on the spot or under a row of chairs;
Pay attention to avoid hanging objects such as chandeliers and electric fans;
Protect your head with a schoolbag, etc.
After the earthquake, listen to the command of the staff and evacuate in an organized manner.
In shopping malls, bookstores, exhibitions, subways, etc.:
Choose solid counters and commodities (such as low furniture, etc.). ) or pillars, and squat down in the inner corner, and protect your head with your hands or other things; Avoid glass doors and windows, glass windows or counters; Avoid tall and unstable shelves or shelves with heavy objects and fragile items; Avoid tall or hanging objects, such as billboards and chandeliers.
In a moving electric (automobile) vehicle:
Grasp the handrail to avoid falling or bumping; Lower your center of gravity and hide near your seat.
Don't get off until the earthquake has passed.
Outdoor shock absorption
Field selection of outdoor shock absorber;
Squat or get down to avoid falling;
Don't run around and avoid crowded places;
Don't go back indoors casually.
Avoid tall buildings or structures:
Buildings, especially those with glass curtain walls;
Crossing bridges and overpasses;
Under tall chimneys and water towers.
Avoid dangerous objects, towering or hanging objects:
Transformer, telephone pole, street lamp, etc. ;
Billboards, cranes, etc.
Avoid other dangerous places:
Narrow streets;
Dangerous old houses, dangerous walls;
Under the parapet, high gate face and awning;
Bricks, wood and other things piled up.
How to save yourself after a strong earthquake
1, after the earthquake, you should actively participate in the rescue work, you can stick your ear on the wall and listen to whether there are survivors.
2. Expose the head of the injured person first and keep breathing smoothly. If suffocation occurs, give artificial respiration immediately.
3. Once buried, try to avoid unstable collapsed objects above your body and try to support the rubble with bricks and wooden sticks. To strengthen the environment.
The earthquake happened in an instant, so anyone should save himself before saving others. First save the easy, then save the difficult; First save near, then save far.
How to identify earthquake rumors
1. To correctly understand the actual level of earthquake prediction at home and abroad, the medium-and long-term predictions made by human beings have certain credibility at present, but the success rate of short-term and imminent predictions is still relatively low.
2. It needs to be clear that in China, the authority to issue earthquake prediction lies with the government, and no other unit or individual has the right to issue earthquake prediction news. Treat earthquake rumors, don't believe them, don't spread them, and report them in time.
3. Learn the common sense of earthquakes and eliminate the fear of earthquakes.
4. Don't believe in rumors and snap up blindly.
When a big earthquake comes, experts suggest that family members should master three principles:
Principle 1: Make the right choice according to local conditions. During the earthquake, everyone's environment and conditions are very different, and the way of shock absorption can't be the same, which needs specific analysis. These conditions include: whether to live in a bungalow or a building, whether the earthquake occurred during the day or at night, whether the house is strong, whether there is room for shock absorption indoors, how far away you are from the door, and whether you are outdoors.