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At 23:59 on December 18, Beijing time, 6Level 2**. As a result, three counties in Haidong City, Qinghai Province, which are adjacent to Jishishan County, have been affected by the disaster, and so far, ** has killed 13 people in Qinghai, and some water, electricity, transportation, communications and other infrastructure have been damaged. Earlier, Gansu Province held a press conference to report that 105 people in Gansu had been killed. 
Rescue work has been actively carried out, and the safety of the people in the disaster area has affected the hearts of hundreds of millions of people. The state has activated an emergency response. There is an urgent need for more than 300 rescue forces such as building collapse search and rescue. The Gansu Provincial Earthquake Relief Field Headquarters and the Gansu Provincial Emergency Management Department hope that the social emergency forces with relevant rescue capabilities will submit an application for participating in the rescue through the social emergency force rescue coordination system. Teams that respond across regions can use the system-generated pass code to achieve high-speed free passage. 
The injured were treated at the People's Hospital of Haidong and Hui Tu Autonomous County in Qinghai Province. Photo by Xinhua News Agency reporter Zhang Hongxiang.
**How can it be divided into "up and down, left and right"?After learning about this ** situation, some netizens raised their own questions:
It turns out that there are two main types of waves that occur when they occur, one is a longitudinal wave with a faster speed but weaker vibration, and the other is a slower wave with a larger vibration. Early warning is the use of longitudinal waves travel faster than transverse waves, and electromagnetic waves are much faster than waves. After the occurrence of the first wave, the longitudinal wave is captured by the first instrument near the epicenter, and then the first wave information is used to quickly calculate the first parameter and the degree of impact, so that the more destructive shear wave can be preempted before the arrival of the shear wave, and the area that may be damaged and affected is alerted.
Since it can be warned, can it be ***?After the occurrence of Gansu **, people in many surrounding areas have received ** warning information pushed by mobile phones. One thing to be clear, the early warning is not a forecast, but an alert. Receive an early warning message indicating that it has been **. It refers to the rapid issuance of an evacuation alarm to the area where the destructive wave has not yet arrived after the occurrence of the virus, mainly to fight for emergency disposal and evacuation time for the public. 
*Early warnings have certain limitations, the closer you are to the epicenter, the shorter the time to provide early warning, and vice versa, but the meaning is also diminished. In addition, because of the "fast" of early warning, the judgment of information such as size and source may not be completely accurate. The accurate and long-term *** is a world problem, the main reasons include the following: ** The occurrence mechanism is complex, and the depth is often 10km, so all research can only rely on indirect observation from the ground.
*The gestation time is long and the scale is large, which is difficult to accurately describe and simulate.
Intense** is uncommon and varies greatly from region to region, making it difficult to repeat observations and tests.
In addition, some people on the Internet publish the so-called "xx phenomenon description is going to be **", here is a unified summary, whether it is to look at animal behavior or observe weather changes to judge**, it is unreliable, this aspect should not believe rumors, do not spread rumors, pay more attention to the official channels of short, temporary forecasts and mobile phone warnings. 
**Come and hide or not?As mentioned earlier, there is early warning information, which includes the epicenter, magnitude, occurrence time, destruction wave arrival time, and most importantly, the estimated intensity of your location. An intensity of 5 degrees is a cut-off. If you can dodge above 5 degrees, you don't need to run if you are below 5 degrees. The concept of 5 degrees is that some of the pendants on the wall in the house may fall down, but the house will not fall.
Photo courtesy of Chen Hong.
Another warning is how many seconds it takes for the S-wave (i.e., longitudinal wave) to reach your location. Like the one shown in the image above, it's 75 seconds. Generally speaking, if a ** will arrive after 75 seconds, it means that it is far away from the epicenter and basically does not need to avoid danger. But if it is level 9**, 75 seconds to come, you have to consider it, because this ** is relatively large, after 75 seconds, the intensity may still be 6 degrees or more than 7 degrees, and you still need to avoid danger. There is a blind spot in the early warning, if it is within the blind spot, you need to perceive the size and distance of the ** yourself. The degree of damage caused by different sizes and distances is different, and the hedging methods adopted are also different. There is no need to avoid distant earthquakes and small earthquakes, but only near earthquakes and large earthquakes need to be avoided. The direction of shaking is different at different distances. A near earthquake is a bump up and down, and then a left, right, back and forth, while a far-shock will not be up and down, but will shake back and forth and left and right for a long time. In other words, when we feel a clear bump up and down, we need to take a hedge. In addition, we should also pay attention to the fact that successful emergency avoidance also requires us to prepare for the earthquake in our daily life, so that we can make correct avoidance behaviors when the first thing happens. In school, work, and daily life, it is necessary to plan a buffer zone for evacuation and an evacuation route for evacuation, that is, where to escape. Be clear about where your home, school, and workplace are safe, and make your own emergency plan. In addition, it is necessary to master and repeatedly practice the best hedging methods in advance.
Photo courtesy of Chen Hong.
**How to hide?
For buildings with weak earthquake resistance, people on the first and second floors of single-storey houses or buildings should be quickly evacuated to a safe area outside, and those on the third floor or above of the building should take shelter nearby. For buildings with strong earthquake resistance, you can take shelter nearby.
When dodging nearby, squat down and curl up, lower the center of gravity of the body, reduce the area, place the forehead between the knees, and protect the head with both hands. If possible, cover your mouth and nose with handkerchiefs, wipes, and other items to prevent dust from falling. If you are in a high-rise residence, because most of the high-rise residences are frame structures, in terms of seismic fortification, our country has considered the seismic standard of "small earthquakes are not bad, medium earthquakes can be repaired, and large earthquakes do not collapse". It's too late to run out of a high-rise building, so you should choose to take shelter in place. We should stay away from the main walls, doors and windows and places with tall furniture, quickly take shelter in small rooms such as bathrooms and kitchens, and then evacuate in an orderly manner along the fire escape after the shaking stopsIn case of aftershocks. It is forbidden to take the elevator during evacuation, and it is not recommended to use ropes to escape when there is **. **From "Civilized Inner Mongolia" WeChat***