Aftershocks can continue for days or even years after the main quake, but they become weaker with time to a point where people don’t feel it, according to Omori’s law in geoscience.
From the first moment that southern Turkey and northern Syria witnessed the earthquake, which was estimated at about 7.8 on the Richter scale, people’s main fears were related to the aftershocks, so that many in the affected areas did not leave the streets. Why?
Earthquakes and their aftershocks
You know earthquakes It is a measure of the energy trapped in the earth’s interior that comes out in the form of light or strong tremors on the surface, and it occurs for several reasons, mainly the movement of the earth’s crust plates relative to each other.
In order to understand what is going on, imagine that the crust that covers the earth is like a paper puzzle in which 20 pieces are intertwined with each other in the same way that puzzles that include a picture must be installed together, and these pieces are called tectonic plates Plate tectonics.
These plates usually move slowly relative to each other at rates of 1-20 centimeters per year, but sometimes these plates overlap together in violent forms, which causes earthquakes to occur, such as what struck Turkey and Syria at dawn on Monday, February 6, and was the strongest on the scale. Since 1939.
But major earthquakes like the one in Turkey are usually followed by what is called “aftershocksAftershocks are relatively large, earthquakes that originate from the same source as the main earthquake.
The reason for this type of additional tremor is related to the main tremor, where the sudden release of energy resulting from the cracking of rocks in the first tremor causes some pressure on nearby rocks, and as pressure builds up, these rocks shatter, triggering a series of smaller tremors.
The possibility of major earthquakes
However, aftershocks are often of a magnitude lower than the main earthquake by a difference of 1.1 to 1.2 on the scale. According to Pat’s law (Båth’s Law) in geology, but the Turkish case was apparently an exception that attracted the attention of scientists, as the country was struck by a second earthquake of 7.5 degrees hours after the first, which means a difference of only 0.3 degrees.
Aftershocks can continue for days and even years after the main earthquake, but they become weaker with time so that they reach a point that people do not feel, according to “.Omori law(Omori’s Law) in Geology.
This is not entirely certain, however, as there is a case, though rare, in which an earthquake is followed by a larger one, and here the first quake is referred to as a “foreshock”.
And this happened before, for example, in 2011 Tohoku earthquake and tsunami In Japan, with a magnitude of 9.1 degrees, it was preceded by an earthquake that occurred two days earlier with a magnitude of 7.3 degrees in the Honshu region, and the authorities thought that it was the main tremor, but it was nothing but a harbinger.
One of the most destructive aftershocks was in Luanxian, China, on July 28, 1976, when a 7.1-magnitude earthquake hit the area, followed by a larger 7.5-magnitude quake that struck the nearby city of Tangshan.
It is worth noting that until the moment these words were written, scientists do not possess any scientific techniques or theoretical mechanisms through which earthquakes can be predicted, except for some attempts through which it is possible to track the reactions of some animals and birds as if they had some kind of early knowledge of the accident.