- A magnitude 7.8 earthquake struck south-central Turkey and northwest Syria, killing over 4000 people and injuring hundreds more.
- An earthquake is a powerful ground tremor caused by movement beneath the earth’s surface.
- It occurs when two earth blocks suddenly slip past one another.
- This releases accumulated ‘elastic strain’ energy in the form of seismic waves, which spread through the earth and cause ground shaking.
Earthquakes
- As we all know, the crust of the Earth is divided into tectonic plates.
- Plate boundaries, which are made up of faults, are the edges of the plates.
- The tectonic plates are constantly moving at a slow pace, sliding past and colliding with one another.
- Because the plates’ edges are quite rough, they get stuck together while the rest of the plate moves.
- When the plate has moved far enough and the edges of one of the faults become unstick, an earthquake occurs.
- The hypocenter is the location beneath the earth’s surface where the earthquake begins, and the epicentre is the location directly above it on the earth’s surface.
How earthquake-prone is Turkey?
- Turkey and Syria are located in a seismically active area.
- The earthquake occurred along a well-known seismic fault line known as the Anatolia tectonic block, which runs through northern, central, and eastern Turkey.
- It is a seismically active zone, though not as active as, say, the Himalayan region, which is one of the most dangerous earthquake-prone areas in the world.
What makes Turkey a hotbed of seismic activity?
- Turkey is frequently shaken by earthquakes. In 2020 itself, it recorded almost 33,000 earthquakes in the region.
- Turkey lies on the Anatolian tectonic plate, which is sandwiched between the Eurasian and African plates.
- The minor Arabian plate on the north side further restricts movement.
- One fault line — the North Anatolian fault (NAF) line, the meeting point of the Eurasian and Anatolian tectonic plates — is known to be “particularly devastating”.
- Then there’s the East Anatolian fault line, which serves as the tectonic divide between the Anatolian Plate and the northward-moving Arabian Plate.
- It stretches for 650 kilometres from eastern Turkey to the Mediterranean.
- Furthermore, the Aegean Sea Plate, which lies in the eastern Mediterranean Sea beneath southern Greece and western Turkey, is a source of seismic activity in the region.
Where was the earthquake epicentered?
- The epicentre of the earthquake was about 33 kilometres from Gaziantep and about 18 kilometres deep.
- Its impact was felt throughout West Asia, Northern Africa, and South Eastern Europe, with residents in Lebanon, Cyprus, Greece, Israel, and Egypt reporting tremors as well.
Many aftershocks hit the region in the aftermath.
- Aftershocks are a series of earthquakes that occur following a larger mainshock on a fault.
- Aftershocks occur near the fault zone where the mainshock rupture occurred and are part of the “readjustment process” following the fault’s main slip.
- While they become less frequent over time, a large mainshock can last for days, weeks, months, or even years.
Are earthquakes predictable?
- An accurate earthquake prediction requires some kind of precursory signal from within the earth indicating that a large quake is on its way.
- Furthermore, the signal must occur only before large earthquakes to avoid indicating every minor movement on the earth’s surface.
- Even if such precursors exist, there is currently no equipment to find them.
- India is willing to help.
- India is one of 45 countries that have offered Turkey assistance so far.
- It is sending search and rescue teams from the National Disaster Relief Force (NDRF) as well as medical teams and relief supplies to the West Asian country.
Source: https://indianexpress.com/article/explained/explained-sci-tech/turkey-syria-earthquakes-seismically-active-zone-the-science-of-quakes-8427982/