The April quakes could have been much, much worse.
The massive earthquake that slammed Nepal was devastating — but not as devastating as it could have been.
A new study published in Science magazine found that the impact of those earthquakes could have far outstripped what actually happened, with landslides far lower than what was possible, according to a BBC report.
In addition, the team found that the Himalayan glacial lakes didn’t suffer any significant damage.
Previous models would have suggested that an earthquake of this magnitude would have had massive effects on the surrounding landscapes, triggering huge landslides that would have wiped out villages and killed untold numbers of people in the country of nearly 30 million people.
It was still quite the catastrophe, with more than eight and a half thousand people dying when the 7.8 quake struck on April 25th, lifting up the Kathmandu basin and causing a large portion of the high Himalayas to sink, shifting the entire region two meters southward. Scientists braced for tens of thousands of landslides, but only 4,312 were detected based on satellite images.
In addition, scientists had expected the earthquake would have caused a breach in the glacial lakes, sending huge volumes of water into the valleys, but this didn’t happen.
Why? Scientists aren’t sure and will need to look deeper into the data, but they have some ideas. One is that the shaking was relatively smooth. Another is that the rocks in the regions are much stronger than had been thought. And finally, the vegetation could have done a good job of binding the landscape together, according to the report.
The latest quake probably differs greatly from massive earthquakes from a thousand years ago. These Magnitude 8 events probably completely changed the landscape, triggering huge debris movements. The second large city in Nepal, Pokhara, is actually built on top of debris from these older quakes.