Earthquake is the ground vibration caused by the dislocation and rupture of underground strata under the action of stress. It is a natural phenomenon like typhoon, rainstorm, flood and lightning.

Earthquake is the first natural disaster. Earthquakes happen every day on the earth, and there are about 5 million earthquakes every year in the world. Most earthquakes are not felt because of their small magnitude. Among them, there were about 50,000 felt earthquakes, nearly 1,000 earthquakes that caused damage, and only a dozen earthquakes of magnitude 7 or above that caused great damage, and most of them occurred in sparsely populated areas.

Basic knowledge of earthquake

The origin of earthquake vibration is called the source; The place on the ground opposite the earthquake source is called the epicenter;

The distance from other parts of the ground to the epicenter is called epicentral distance; The distance to the source is called the source distance;

The vertical distance from the epicenter to the source is called the focal depth.

How to prevent shock in school-

In class, under the command of the teacher, hold your head quickly, close your eyes and hide under the desk.

When in the playground or outdoors, you can squat down and cover your head with your hands. Pay attention to avoid tall buildings or dangerous objects.

Don't go back to the classroom

Evacuation should be organized after the earthquake.

Classes should be held outdoors when necessary.

China is a country with many earthquakes.

China is located between the Pacific Rim seismic belt and the Eurasian seismic belt, squeezed by the Pacific plate, the Indian plate and the Philippine Sea plate, and the seismic fault zone is very developed. Since the beginning of this century, there have been nearly 800 earthquakes of magnitude 6 or above in China, covering all provinces, autonomous regions and municipalities except Guizhou and Zhejiang provinces and the Hong Kong Special Administrative Region.

China is a country with severe earthquake disasters because of its high frequency, high intensity, shallow focal point and wide distribution. Since 1900, the number of earthquake deaths in China has reached 550,000, accounting for 53% of the global earthquake deaths; Since 1949, destructive earthquakes have occurred in 22 provinces (autonomous regions and municipalities directly under the Central Government) 100 times, including the eastern region 14 provinces, resulting in more than 270,000 deaths, accounting for 54% of all kinds of disaster deaths in China, with an earthquake-affected area of more than 300,000 square kilometers and 7 million houses collapsed. The severity of natural disasters such as earthquakes is one of the basic national conditions in China.

The seismic activity in China is mainly distributed in 23 seismic zones in five regions.

The seismic activity in China is mainly distributed in 23 seismic zones in five regions. These five areas are: ① Taiwan Province Province and its adjacent waters; (2) Southwest China, mainly Tibet, western Sichuan and central and western Yunnan; (3) Northwest China, mainly distributed in Hexi Corridor of Gansu, Qinghai and Ningxia and the foothills of Tianshan Mountain; ④ North China, mainly located on both sides of Taihang Mountain, Wei Fen Valley, Yinshan-Yanshan area, Luzhong and Bohai Bay; ⑤ Southeast coastal areas such as Guangdong and Fujian. Taiwan Province province in China is located in the Pacific Rim seismic belt, Tibet, Xinjiang, Yunnan, Sichuan and Qinghai provinces are located in the Himalayan-Mediterranean seismic belt, and other provinces are located in related seismic belts. The distribution of China's seismic zones is an important basis for formulating key earthquake monitoring and defense areas in China.

Earthquake knowledge

First, in the face of earthquakes, how to prevent earthquakes and reduce disasters?

When an earthquake happens, it is very important to keep a clear head and a calm attitude.

If you are indoors during the earthquake, if you are far away from doors and windows, it will be safer to temporarily hide under solid furniture or in a corner. In addition, you can also move to the kitchen, bathroom and other places with more load-bearing walls and smaller rooms for temporary shelter. Avoid the main earthquake and quickly evacuate to the spacious outdoor. Pay attention to protect your head when you evacuate. It is best to protect your head with soft objects such as pillows and quilts.

If you are outdoors in an open place during the earthquake, it is the luckiest thing. If you are in a dense building, it is best to cover your head with soft objects such as hands or wallets, and prepare for self-defense as much as possible. And quickly leave transformers, telephone poles and fences, narrow lanes, etc.

There will be endless secondary disasters in earthquakes, so we should take flexible emergency measures according to different situations.

Second, how to rescue in case of danger?

People buried under the rubble in the earthquake should cover their nose and mouth with towels and clothes to avoid choking by smoke. They should also try to get rid of all kinds of things that are on their bodies, and it is best to move to a place with light. When you can't get out of danger, try to reduce the consumption of strength. The longer you persist, the more likely you are to be saved. In addition, people outside are not easy to be heard under the rubble, so wait until you hear someone outside before calling for help or knocking on the wall.

When rescuing others, you should first determine the position of the wounded's head, so that the head is exposed first, quickly remove the dust in the nose and mouth, and then expose the chest and abdomen. Don't pull hard If there is suffocation, artificial respiration should be carried out in time.

How to carry out personal protection during an earthquake?

When you feel the ground or buildings shaking, remember that the biggest damage comes from falling debris. At this time, you should move cleverly to avoid it.

1, in the house, quickly hide in a safe place, such as hiding under a desk, workbench or bed. In the unit building, you can choose to open a small bathroom and corner, relying on the support of water supply and drainage pipelines and gas pipelines to reduce casualties. For workers who live in outdoor bungalows, they can escape outdoors with quilts, pillows or helmets on their heads during the earthquake. When it's too late, it's best to stay indoors for shock absorption. Be careful to stay away from the window. When you come down, put your head against the wall, so that the concave part between your eyes above your nose rests on your horizontal arm.

Close your eyes and mouth and breathe through your nose. Generally speaking, don't run out of the building. It is best to find a safe place nearby. After the earthquake, if you need to evacuate, leave calmly.

2. In case of earthquake, the door frame will not open due to deformation, so it is best not to close the door when it is earthquake-proof. When there is an earthquake at night, we should race against time to move to a safe place. Don't waste time looking for things and dressing up. If possible, turn off the power supply, gas and fire immediately. It is best to use a flashlight for lighting, not matches, candles and other open flames.

3. During an earthquake, if you have been smashed or buried under a collapsed object, you should first observe the surrounding environment, find a passage, and try to escape. If there is no passage, you should save your strength, don't make a hullabaloo about, and listen to what is going on outside. If you hear someone passing by, you can knock on the iron pipe or wall to make the sound come out for rescue. At the same time, we should find life-sustaining food in a narrow space.