Every year, more than 200,000 earthquakes are recorded on our planet, although, according to estimates, several million occur.
Many go undetected because they are too slight for us to feel, or because they occur in remote areas that are not monitored.
Others, such as those that occurred on Monday in Turkey and Syria (the first of 7.8 magnitude and the second, regarding 12 hours later, from 7.5 magnitude) cause numerous fatalities and cause entire buildings to collapse.
Building earthquake-proof houses and buildings is obviously the best strategy to avoid both human and material losses. Evacuating areas that will be affected in advance —as in the case of a hurricane— would also contribute in this regard.
However, the latter cannot be done —except a few minutes before— since, earthquakes are impossible to predict.
Because? What is it regarding telluric movements that scientists cannot say with certainty when they will occur?
physical law
Most earthquakes are caused by sudden release of tension in the earth’s crust.
This tension gradually builds up due to tectonic movements, usually along a geological fault line, the Geological Society of the United Kingdom explains on its website.
But it is impossible to predict when it will happen, “basically because of the way that stress is released”Richard Luckett, a seismologist with the British Geological Survey, explains to BBC Mundo.
“We know the stress is building up on the big faults and we know where they are, but we have no way of knowing when they’re going to release it,” he says.
To help us understand the problem, Luckett uses the example of an experiment that he usually does to explain this phenomenon to children.
“If you put a brick on a piece of sandpaper and slowly pull the paper back with a spring, the brick will move. You can repeat this experiment 10 times, and even if you apply the same force each time, you will find that the brick will move suddenly. following different time intervals,” says Luckett.
“In physical terms es completely unpredictable“.
What the experts can at least know is where there is a probability of a high-intensity earthquake occurring, “since these are related to the size of the fault,” Luckett clarifies.
However, this does not help to predict what the intensity of an earthquake will be, since pressure can be released in a series of small earthquakes or in one large earthquake.
In the case of the event that caused damage in Turkey and Syria, there were two strong tremors in a row.
The animals that can warn us
And aren’t there other signs, such as a change in the weather or in the behavior of animals that can help us predict a telluric movement?
“Earthquakes have no nothing to do with the weather and certainly not a connection to climate change“clarifies the scientist.
“They are completely different systems.”
But the case of animals is interesting, he adds.
Much has been reported for some time regarding how some animals display different behavior in the face of an imminent earthquake.
It is said that dogs bark more or that animals are noisier in general.
This is because “when there is a large earthquake at a great distance, it causes different waves that travel across the land. The former are very small, do no harm, and many times we don’t even notice them,” says Luckett.
neither now nor later
Even so, this is not very helpful when it comes to predicting an earthquake either.
“Animals feel these vibrations, but this happens once the earthquake has already occurred“says the expert.
“They warn us of danger a little earlier (the time depends on the pause that occurs between the small waves and the larger ones), in the same way that alarms do.”
“And in this sense, devices are more sensitive than animals.”
In short, the expert believes that it is not —and will not be— possible to predict earthquakes.
“What can be done is polish the way of detecting las odds“.
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