Earthquake prevention and disaster reduction  peace is always there

Earthquake, also known as ground motion and ground vibration, is a natural phenomenon in which seismic waves are generated during the rapid release of energy from the earth's crust.

According to the causes of earthquakes, earthquakes can be divided into tectonic earthquakes, volcanic earthquakes, collapse earthquakes, induced earthquakes and artificial earthquakes. More than 90% of earthquakes and almost all destructive earthquakes in the world belong to tectonic earthquakes. This type of earthquake has a wide range and is very destructive. For example, the Tangshan earthquake and the Wenchuan earthquake belong to this category.

To understand the causes of earthquakes, we must first understand the internal structure of the earth. The Earth is divided into three layers: the central layer is the core, the middle is the mantle, and the outer layer is the crust. The top part of the crust and mantle forms a lithosphere with a thickness of about 60 to 120 kilometers. The lithosphere is above the asthenosphere in the upper part of the upper mantle, floating on the magma surface like a board floating on water. These plates move relative to the influence of magma and the external environment. In the process of moving, it is inevitable that the plates will collide with each other, peel off and die. It will lead to the deformation and extrusion of the rock. When this effect accumulates to a certain extent, the frictional fracture of the rock will generate elastic waves in the crust, and a tectonic earthquake will be formed. Most earthquakes worldwide occur on the boundaries of large plates.

According to statistics, more than 5 million earthquakes occur every year on the earth, that is, tens of thousands of earthquakes occur every day. Most of them are too small or too far to be felt; but very few destructive earthquakes can cause great harm to human life and property.

Disasters caused by earthquakes are first to destroy houses and structures. For example, in the 1976 earthquake in Tangshan, Hebei, China, 70% to 80% of the buildings collapsed, resulting in heavy casualties. In cities and towns, earthquakes can also cause bridges to fall, dams to crack, and railway tracks to deform. If gas, toxic gases and radioactive substances leak, it may lead to secondary disasters such as fire, toxic gas pollution, radioactive pollution, and plague.

Earthquakes can also cause landslides and landslides, burying villages. Collapsing rocks block the river.

In coastal areas, earthquakes will cause seawater to oscillate, and large areas of water will suddenly rise or fall, resulting in seismic tsunamis as high as 20 to 30 meters. The 2004 tsunami triggered by a 7.9-magnitude earthquake in Indonesia killed 240,000 people.

Predicting earthquakes is a long-term desire, but it is currently impossible to accurately predict the magnitude and timing of earthquakes. Therefore, personal awareness of disasters and earthquake prevention and self-rescue are important aspects of earthquake resistance and disaster reduction.

To learn earthquake knowledge, prepare an earthquake emergency kit, which should contain: compressed dry food, emergency drinking water, ultra-thin thermal insulation raincoat, hard hat, folding bucket, multi-function emergency flashlight, emergency call post, non-slip gloves, candles, matches, etc.

When an earthquake occurs, if we are in a high-rise building, we should not panic. At this time, we need to find a safe shock-absorbing space as soon as possible, such as sheltering in the bathroom, or a kitchen with many load-bearing walls and a small bay. Do not take the elevator at any time. If you are in a shopping mall and encounter an earthquake, keep calm and evacuate in an orderly manner to avoid collision or stampede incidents. If an earthquake occurs during class, you should quickly hold your head and close your eyes under the instruction of the teacher. , hiding under their respective desks.

If you are outdoors, avoid tall buildings, high-voltage lines and toxic factories or facilities such as petrochemicals, chemicals, and gas. If you can't find a place to cover, immediately take the posture of lying on the ground with your hands and knees on the ground

In the unfortunate event that the house collapses and is buried in the rubble, keep calm. If part of the limb is buried, first clear a certain space on the head and chest with your hands.

Earthquakes are unavoidable, but as long as we take scientific and reasonable methods to save ourselves, we can minimize the damage of disasters.