look news india
Whenever the havoc of nature strikes, huge concrete structures and skyscrapers made by humans fall apart like a deck of cards. A similar horrifying scene is currently being seen in the South American country Venezuela, which is facing one of the most gruesome and destructive natural disasters in its history.
Venezuela was hit by two back-to-back powerful earthquakes within minutes, turning cities into piles of debris. The videos and pictures coming out from the capital Caracas to different provinces of the country are giving goosebumps. More than hundreds of buildings have been completely destroyed and the country’s main international airport has also collapsed. According to preliminary satellite calculations of the US Geological Survey (USGS), the death toll in this catastrophe may exceed 10 thousand. In view of the situation, State of Emergency has been imposed in the entire country and red alert of tsunami is issued in the sea.
Mathematics of the ‘double attack’ that shook Venezuela
According to meteorological and geological scientists, both the intensity and depth of this earthquake in Venezuela were extremely dangerous:
-
First blow: Its intensity measured 7.1 on the Richter scale, with its epicenter about 160 kilometers west of the capital Caracas and at a depth of just 13 kilometers from the ground.
-
Second blow: A few seconds after the first shock, a second and more powerful earthquake of magnitude 7.5 occurred, whose epicenter was only 10 kilometers underground, 16 kilometers southwest of the city of Moron.
Why do such terrible earthquakes occur? Know the science behind it
After the Venezuela accident, this question is arising in everyone’s mind that what happens inside the earth that causes such destructive earthquakes? If understood from the scientific point of view, the following 4 major movements occurring in the deep layers of the earth are responsible for these terrible tremors:
1. Tectonic Plates colliding with each other
Our Earth may look like a solid ball from above, but its inside structure is completely different. The uppermost layer of the Earth (Crust) is not a monolithic piece, rather it is made up of 7 big and many small plates, which are called tectonic plates. These plates are continuously floating at a very slow speed on the molten lava (magma) present inside the earth. When these floating plates collide with each other, slide under each other, or rub against each other, a vibration is produced on the surface which we call an earthquake.
2. Heavy pressure on fault lines (Fault Lines)
Where the boundaries or edges of two tectonic plates meet, that weak joint is called a fault line. Often, while moving, these plates get badly stuck together and are unable to move forward. But due to the internal pull of the Earth, the pressure from behind does not reduce. Due to this, a huge amount of elastic energy i.e. strain energy starts accumulating at that trapped place (fault line) for years.
3. Sudden release of energy
When this pressure exceeds the bearing capacity (limit) of the rocks, the rocks on the fault line suddenly break or slip in one fell swoop. As soon as this happens, the tremendous energy that has been stuck for years comes out in the form of ‘seismic waves’ within a second. This is exactly like a spring being suddenly released after pressing it too much with the hands. When these waves reach the earth’s surface, they bring great destruction.
The severity of an earthquake is determined by these 3 things
How dangerous or destructive any earthquake will be depends mainly on three technical parameters:
| scale | What does this mean? | Effect |
| Magnitude | How much energy was released due to the breaking of the fault line. | Earthquakes with a magnitude of more than 7 are always destructive. |
| Depth of Focus | The exact point inside the Earth where an earthquake begins is called the focus or hypocenter. | The closer the focus is to the surface (like 10-20 km inside), the more severe the devastation will be. |
| Epicenter | The point on the earth’s surface immediately above the focus. | Earthquake tremors are strongest and damage is maximum at this centre. |
Why did such a big earthquake occur in Venezuela?
According to geographical and geological structure, Venezuela falls in the world’s most sensitive seismic zone. This country is mainly Caribbean Plate And South American Plate It is situated exactly at the meeting point of.
Scientists believe that these two huge tectonic plates are continuously creating tremendous pressure in opposite directions to each other. This pressure that had been accumulating for years suddenly came out due to the rupture of the fault line near the city of Moron, due to which this ‘catastrophe’ has occurred in Venezuela.