Of course, even among the people, there are many phenomena that can predict earthquakes, such as shaking clouds, shaking fish, fish jumping out of the water, cats and dogs making abnormal noises, and of course many people believe it? There must be a big earthquake after the drought? . So, does a drought necessarily mean a big earthquake? Are the legendary abnormal natural phenomena and abnormal behaviors of various animals really a precursor to the coming earthquake?
Why are earthquakes called natural phenomena?
First of all, we must clarify a basic fact. Earthquakes actually happen frequently from the earth to the moon. I believe some people know what the environment of the moon is like. There is no such thing as drought. Moreover, earthquakes are very common natural phenomena. In a short day, the number of earthquakes in all corners of the earth can add up to more than 10 thousand, because the average number of earthquakes on the earth is about 5 million a year.
At this time, some people may say, why are there not so many known earthquakes? This is actually not surprising. Earthquakes are called natural phenomena because they are not only common, but also generally do not have much impact on people around them. Although there are more than 5 million earthquakes in the world every year, only 10 to 20 of them may cause harm to people in the epicenter, and earthquakes that can cause serious disasters are about once or twice a year.
Why didn't we feel so many earthquakes?
People seldom feel the occurrence of earthquakes, mainly because most earthquakes are relatively small in magnitude, and earthquakes less than magnitude 3 are usually difficult for human beings to feel clearly. Of course, the earth is so big that not all the places where earthquakes occur are close to us. In terms of seismic wave propagation, it also has its own maximum propagation range, which depends entirely on the depth of the earthquake and the total energy released.
When man landed on the moon, instruments were specially placed to measure the ground vibration, so as to know whether earthquakes and other phenomena also existed on other planets. On the earth where we live, there are actually many specialized seismic measuring instruments in many corners, and the number can be said to be thousands. It is these detectors that record earthquakes that collect the information of each earthquake that we know how destructive the earthquake is and how many people need to participate in disaster relief.
Is there a necessary relationship between earthquake and drought?
Just think, if there is a drought or a severe drought before every earthquake, then the number of earthquakes should be far less than the actual number, and there are even fewer places where earthquakes occur! Moreover, it takes too long to link the earthquake in a place with the drought in three years, and it cannot fundamentally reduce the risks to people's lives and property when the earthquake occurs.
There are many types of earthquakes, but generally speaking, the most destructive earthquakes are caused by the energy released by the earth's crust, and they are often in shallow earthquakes, such as the Wenchuan earthquake and the Ya 'an earthquake, which are relatively close now. This kind of shallow earthquakes with a large magnitude will not only threaten people's lives when an earthquake occurs, but also cause secondary natural disasters such as landslides and mudslides if there is heavy precipitation in a short period of time in the following years.
But the main indicator of drought is that the total amount of fresh water in this area is too small, which is called natural disaster, and the impact of drought on agriculture is particularly obvious. The main cause of drought is closely related to natural factors such as meteorology. When there is little or no rain in a place for a long time, several types of droughts may occur, such as soil drought, atmospheric drought or physiological drought. Of course, global warming caused by human activities is also one of the reasons for frequent droughts in recent years.
Does the earthquake have a so-called omen?
People are so afraid of earthquakes and collect a lot of information that may indicate the occurrence of earthquakes because they are afraid that sudden earthquakes will endanger their families and their lives. But the fact will disappoint everyone, because so far, drought has not been determined to have an inevitable relationship with the occurrence of earthquakes. Generally speaking, the probability of earthquakes in areas with earthquake zones is higher than that in areas without earthquake zones. At present, earthquakes with large magnitude only occur in areas with seismic zones, and earthquakes in other areas are generally less than magnitude 6.
Moreover, not only can we not regard drought as a sign of an earthquake, but we can't believe that any earthquake clouds and fish can predict an earthquake. When the earth's crust suddenly releases energy, even some animals that are considered more spiritual can't predict it before it happens. It is only coincidence that people find some abnormal sounds after some earthquakes. Otherwise, many years later, how can scientists not predict the occurrence time of earthquakes in advance?