I found this table revealing if specious:

Richter TNT for Seismic Example
Magnitude Energy Yield (approximate)

-1.5 6 ounces Breaking a rock on a lab table
1.0 30 pounds Large Blast at a Construction Site
1.5 320 pounds
2.0 1 ton Large Quarry or Mine Blast
2.5 4.6 tons
3.0 29 tons
3.5 73 tons
4.0 1,000 tons Small Nuclear Weapon
4.5 5,100 tons Average Tornado (total energy)
5.0 32,000 tons
5.5 80,000 tons Little Skull Mtn., NV Quake, 1992
6.0 1 million tons Double Spring Flat, NV Quake, 1994
6.5 5 million tons Northridge, CA Quake, 1994
7.0 32 million tons Hyogo-Ken Nanbu, Japan Quake, 1995;
Largest Thermonuclear Weapon
7.5 160 million tons Landers, CA Quake, 1992
8.0 1 billion tons San Francisco, CA Quake, 1906
8.5 5 billion tons Anchorage, AK Quake, 1964
9.0 32 billion tons Chilean Quake, 1960
10.0 1 trillion tons (San-Andreas type fault circling Earth)
12.0 160 trillion tons (Fault Earth in half through center,
OR Earth's daily receipt of solar
energy)

http://www.seismo.unr.edu/ftp/pub/lo...magnitude.html

With all due respect to those who compiled it, it is hard to see how
the accuracy can be maintained so evenly. But then it is probably
similar to my efforts, no more than a rule of thumb.

My stuff fits in there somewhere between the 6.5 to 8 mag quakes. A
super-typhoon will cause the same amount of input to an international
weather model run as a 7 to 7.5 quake. Give or take a few million tons
of TNT.

I liked that bit at the end about the value of the insolation for one
day.