Why are earthquakes unpredictable?

Because earthquake prediction must include time, place and intensity at the same time, some earthquakes can be predicted, and some earthquakes can't. Moreover, some seismologists affirmed the achievements of earthquake prediction, thinking that the short-term prediction of earthquake location, time and magnitude will eventually be realized, while the long-term prediction will be more prominent.

The strongest ground motion of a destructive earthquake is called the extreme earthquake zone, which is often the area where the epicenter is located. Earthquakes often cause serious casualties, which can cause fires, floods, toxic gas leakage, the spread of bacteria and radioactive substances, and may also cause secondary disasters such as tsunami, landslides, collapses and ground fissures.

Extended data:

Waves whose vibration direction is perpendicular to the propagation direction are shear waves (S waves). Shear waves from underground will cause horizontal ground vibration. Because the propagation speed of longitudinal waves in the earth is faster than that of shear waves, in earthquakes, longitudinal waves always reach the surface first, while shear waves always lag behind. In this way, when a recent earthquake occurs, most people will feel up and down at first, and it will take a few seconds to ten seconds to feel a strong horizontal shaking. Shear waves are the main cause of damage.

Because the earth's rotation and revolution are endless, and its internal materials are constantly differentiated, the crust around the earth's surface, or lithosphere, is also constantly generated, evolved and moved, which has contributed to the global crustal tectonic movement. Scientists have experienced long-term observation, description and analysis of crustal structure and land-sea changes, and have successively formed different hypotheses, ideas and theories.

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