Why Nepal is Still Being Hit by Aftershocks

Aftershocks are forecast-able not predictable. This means that current science can't calculate exact time, magnitude and intensity of aftershocks. Nor can it say when it stops. However it's pretty simple to know how it stops.

Aftershocks in Nepal are still active. This is definitely surprising. It is because of the amazing nature of the mainshock. So there is no need to worry. They are normal. If this earthquake and aftershocks had not been of such nature, we would have faced much shaking during the mainshock and that could have been much devastating. Anyway we want to see these aftershocks stopped. So here rises the question how to know if aftershocks stopped?

Photo Credit: NSC
There are 3 conditionals to be fulfilled to confirm aftershocks stopped:
1. Aftershocks disappeared for longer time
It's pretty easy to say aftershocks stopped if there is no aftershock more than 4 M for longer time.

2. Earthquake occurred in other than the rupture zone
If aftershocks are not taking place for longer time and regular earthquake took place in other than the rupture zone, this is strong evidence to say that aftershocks have stopped.

But there is an important thing to remember that aftershocks can occur even nearby {a bit farther} the rupture zone due to the stress created by the ongoing aftershocks. So only the aftershocks very far from the rupture zone should be taken as an independent earthquake.

3. Aftershocks are absent after the independent earthquake
If aftershock stroke again after an independent earthquake, It is sad to say that this is not the end of the aftershocks. They should not appear again.

If those 3 levels are completed, we can believe that the earthquake sequence of Nepal has gone to the pre earthquake level and we won't be facing aftershocks later.
Discovered by Don Prince

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