Earthquake magnitudes

From Wikipedia

Northridge earthquake, 1994. Magnitude 6.7. Equal to 5.6 megatons

Sichuan earthquake, 2008. Magnitude 7.9. Equal to 600 megatons

The Richter Scale is logarithmic. Thus, an 8.0 can be hugely more destructive than a 7.0.

I was in L.A. during the Northridge quake. It did tremendous damage. But this China quake was vastly more powerful than that.