Afghanistan’s Deadliest Earthquake in Years

What’s in today’s article?

• Why in news?
• What is an Earthquake? 
• What is Alpide Belt?
• News Summary: Afghanistan’s deadliest earthquake in years
• Why do so many devastating earthquakes happen in Afghanistan?

Why in News?

• More than 2000 people have been killed and over 9,000 injured following powerful earthquakes in Afghanistan.
• As per the U.S. Geological Survey, the quakes hit 35 km northwest of the city of Herat on Saturday, with one of them measuring 6.3 magnitude.
• It was followed by three very strong aftershocks, measuring magnitude 6.3, 5.9 and 5.5, as well as lesser shocks.

What is an Earthquake?

• An earthquake is an intense shaking of the ground caused by movement under the earth’s surface.
  • The location below the earth’s surface where the earthquake starts is called the hypocentre.
  • The location directly above the hypocentre on the surface of the earth is called the epicentre.
• It happens when two blocks (tectonic plates) of the earth suddenly slip past one another releasing stored-up ‘elastic strain’ energy in the form of seismic waves.
• These spread through the earth and cause the shaking of the ground.
• They are measured on scales called the -
  • Moment Magnitude Scale (Mw), based on the total moment (a product of the distance a fault moved and the force required to move it) release of the earthquake.
  • The Richter scale (magnitude scale) - energy released - 0-10.
  • The intensity scale/Mercalli scale - visible damage - 1-12.
• Earthquakes continue to remain the most common natural hazard that cannot be predicted as no early warning systems can be developed.

What is Alpide Belt?

About:

• The Alpide Belt spans over 15,000 km, roughly following the boundary of the Eurasian and African tectonic plates.
  • It spans from the Middle East to the Himalayas and Indonesia.
• It extends from the Himalayas in the east, through the Mediterranean region and across to the Azores in the Atlantic Ocean.
• Tectonic plates are formations of the Earth’s crust that move slowly, often creating pressure and friction between each other.

Earthquake prone:

• Albide Belt is the second most active region on Earth after the Pacific Ring of Fire.
• This belt experiences a high frequency of earthquakes and volcanic eruptions.
• This is primarily due to the collision of the Eurasian and African tectonic plates, which drag along and cause a build-up of immense pressure.
• This slow-building pressure eventually gets released through earthquakes and volcanic activity.
• One of the deadliest natural disasters in history — the 2004 Indian Ocean earthquake, which led to a massive tsunami that killed about 200,000 people — fell within this belt.

News Summary: Afghanistan’s deadliest earthquake in years

• In the deadliest tremors in years in the quake-prone country, powerful earthquakes in Afghanistan have killed more than 2,000 people and injured more than 9,000.

Why do so many devastating earthquakes happen in Afghanistan?

• Afghanistan is earthquake-prone because it's located in the mountainous Hindu Kush region, which is part of the Alpide belt.
  • Alpide belt is the second most seismically active region in the world after the Pacific Ring of Fire.
• Additionally, the Earth's crust is especially lively in Afghanistan because it is where the Arabian, Indian and Eurasian tectonic plates meet.
  • The boundary between the Indian and Eurasian plates exists near Afghanistan's border with Pakistan.

• Death tolls often rise when remote locations are hit, and decades of war have left infrastructure in a shambles, making relief and rescue operations difficult.

Q1) What are tectonic plates?

Tectonic plates are large, irregularly shaped slabs of solid rock that make up the Earth's crust and uppermost mantle. They are also called lithospheric plates. Tectonic plates are made up of: Continental lithosphere, Oceanic lithosphere, Oceanic crust, Continental crust.

Q2) What is Hindu Kush region?

The Hindu Kush is a 500-mile-long mountain range in Central and South Asia. It stretches from central and eastern Afghanistan into northwestern Pakistan and far southeastern Tajikistan. The Hindu Kush is part of the Hindu Kush Himalayan (HKH) region, which extends 3,500 km over all or part of eight countries from Afghanistan in the west to Myanmar in the east.

Source: Afghanistan earthquake kills 2,000: The frequent tremors the country sees | World Atlas | The Print | BBC