About an hour ago a 4.2 magnitude earthquake hit Donchuan county, about 115km North of Kunming.

m.sohu.com/a/406382173_260616/?pvid=000115_3w_a

Did anyone feel anything?

Not a wobble....

4.2 is too small to feel.

4.2 is tiny. Richter scale is a logarithmic scale. Essentially, each successive magnitude is 33 times larger than the last. That means a magnitude-8.0 earthquake is 33 times stronger than a 7.0, and a magnitude-9.0 earthquake is 1,089 (33 x 33) times more powerful than a 7.0 — the energy ramps up fast. Working the other way, each successive magnitude smaller, and the movement quickly diminishes to not noticeable, especially at 150 km.

I'm no expert, but my quick internet search seems to imply each Richter magnitude is TEN times the previous one, not 33?
socratic.org/questions/what-is-the-richter-scale-1

@dandare
I think we are both confusing earthquake "power" ie Richter Scale with earthquake "magnitude" ie Moment Magnitude Scale.. I've learned something today!
www.latimes.com/[...]

Thanks Ocean.

That article was very informative.

It did leave me with one question though.

Which of the two intensity scales is being used in modern reporting?

The article didn't mention that specifically.

@Alpage
Not sure. The LA Times article says, "...the Richter scale was eventually scrapped in favor of what is known as the moment magnitude scale" but that's news to me! Most people would still think "Richter" if you talk about the size of an earthquake.

@Ocean, you are right. I was confusing the scales. The old Richter scale is the one that is logarithmic 10x. The Moment Magnitude scale isn't, but is more extreme. I also leaned today.