[Phsstpok]

8.5 is big, the last one was a 9.0.

The scale is logarithmic, so a 9 is ten times more than an 8, 100 times more than a 7, etc.

I guess that makes the 9 five times greater than the 8.5? IOW the 8.5 is 1/5, or 20% of the 9.0 in December?

[Strategerist]

Well, there's some evidence the December quake was a 9.3.

It's logarithmic, 10 times the GROUND MOTION for each number increase;

However, it's 32 times the ENERGY for each full point of magnitude.

[Truthsearcher]

With the log scale an 8.5 is about 3 times the strength of 8 and about 1/3 the strength of a 9.0