How to make earthquake prediction with mobile phone?

The mobile phone earthquake prediction is done as follows: seismic waves are detected by sensors such as built-in seismic sensors, and when the mobile phone senses vibration signals, it can realize local calculation to determine seismic wave signals.

Radio waves travel much faster than seismic waves, and different types of seismic waves travel at different speeds. People can use these time differences to realize earthquake early warning. After the earthquake, the released energy propagates underground in the form of seismic waves, including longitudinal waves and shear waves. Because the longitudinal wave generated by the earthquake travels faster than the more destructive shear wave, it can reach the ground first and "ventilate" the early warning system.

At the same time, it takes time for an earthquake to spread from the source to a certain area (that is, the ratio of propagation distance to seismic wave velocity), so people can use this time difference to race against the earthquake and realize early warning. When the seismic monitoring station detects the first P wave (longitudinal wave), the system will give an alarm after processing the information. The projection point of the source on the surface is called the epicenter, and the spherical distance from a certain point to the epicenter is the epicentral distance.

Therefore, the longer the epicentral distance, the longer the early warning time. The earthquake that occurred in Pingyuan County, Dezhou City, Shandong Province on August 6 made many areas feel obvious, including Beijing, Tianjin, Shijiazhuang, Taiyuan and Zhengzhou. The warning time varies from a few seconds to dozens of seconds, depending on the distance from the source.

Distinguish between earthquake early warning and earthquake prediction;

Earthquake early warning uses the principle that the propagation speed of electric waves is faster than that of seismic waves. After an earthquake occurs but before the seismic waves reach a certain area, the early warning target is warned to minimize casualties.

"Forecast" refers to the pre-announcement that has not yet happened but may happen, such as the weather forecast with a high probability of rain tomorrow. Whether it will rain tomorrow, we can't give a definite answer in advance. It is influenced by many factors, so it is a probabilistic event. Earthquake prediction is different from weather prediction and has the principle of "uncertainty without notice", that is, social credibility needs to be considered. If the authoritative department predicts earthquake mistakes many times, it will have a negative impact on people's thinking.