Afghan Earthquake: Continental Collision

By Mariano Castillo, Sophia Saifi and Masoud Popalzai, CNN
Updated 5:29 PM ET, Mon October 26, 2015 | Video Source: CNN

Kabul, Afghanistan (CNN)The powerful earthquake that struck northeastern Afghanistan on Monday also rattled people in Pakistan, India and Tajikistan, killing dozens, collapsing structures and creating panic.

Earthquake - Afghanistan and Pakistan

Monday’s magnitude-7.5 earthquake was similar to a magnitude-7.6 quake in nearby Kashmir that killed more than 70,000 in 2005. But unlike the quake 10 years ago, this one happened deep inside the Earth, some 223 kilometers (139 miles) below the surface.

Earthquakes at this depth typically cause less damage on the surface than shallower quakes, according to the U.S. Geological Survey.

Northern Pakistan has seen recent heavy rains, and there are fears the quake may have triggered landslides.

In the Hunza Valley in that region, the quake reportedly shook loose a landslide at a mountain glacier. Photos circulated on social media.

Source: CNN | Deaths, damage reported in powerful Afghanistan quake

By Jonathan Webb
Science reporter, BBC News 6 hours ago

Very large but mercifully deep: this appears to be the view of scientists analysing the deadly earthquake in Afghanistan.

The shaking caused landslides in some mountainous regions, like this one in the Hunza valley of Pakistan (Image copyright AMIN SAIF/Getty Images via BBC)
The shaking caused landslides in some mountainous regions, like this one in the Hunza valley of Pakistan (Image copyright AMIN SAIF/Getty Images via BBC)

Initially measured by the US Geological Survey as magnitude 7.7, the quake is now listed by the USGS as magnitude 7.5.

Even this revised assessment makes Monday’s event a terribly powerful tremor. Around the world, only about 20 quakes each year, on average, measure greater than magnitude 7.0.

But the origin of the shaking was more than 200km (125 miles) below the surface – much deeper than the magnitude 7.8 quake that brought widespread destruction to eastern Nepal in April. That event was only 8km deep and was followed by many aftershocks, including one in early May of magnitude 7.3.

Similarly, the devastating tremor that killed tens of thousands in Kashmir almost exactly 10 years ago was magnitude 7.6 – and just 26km deep.

The much greater depth of Monday’s quake appears to have lessened the ground shaking that it produced, although its effects were felt over a wide area.

Source: BBC | Afghan quake: The corner of a continental collision

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.