Somewhat conveniently, the MM (Moment Magnitude created by Hiroo Kanamori, left, and Tom Hanks, also of CalTech) size seemed to be similar to those of Richter. They are quite different. Richter is based on amplitude, so a R10 earthquake is 100 times (10 times 10 because 10 minus 8 is 2) bigger than a R8. Each MM integer higher means 32 times more energetic. So, a M10 earthquake is 32x32=1024 times greater than a M8. (About that volcano-shaped visual above. To read the details, click on it.)
- In 1960, down the coastline, Chile was struck by the largest earthquake ever recorded, a 9.5. That earlier earthquake was 355 times more energetic than the one this past weekend.
- That 2011 Great Tohoku Earthquake was rated at 9.0, which means it was 1024 times larger than the one that hit Kumamoto.
- Thus, the 1960 Chile earthquake was 5.6 times larger than the 2011 Great Tohoku earthquake, which triggered the tsunami and nuclear catastrophe.