chemisttree said:
Just curious, what’s “Mw?”
Mw = Moment Magnitude, it's the main one now used ( for ~ the last 25 years or so ).
It gives a better representation of the size of the quake and it doesn't suffer from the recording overload
that all the older magnitude do, eg the more commonly ones like ML (Local Magnitude = the old Richter scale),
Mb (Body wave Magnitude), MS = Surface Magnitude ( used to be used for the large non-local events).
ML is still commonly used for quakes within ~ 200 km of the recording station. It was never intended for use
for big distant event. But as usual with the media, they latch onto something and won't let it go and ML
gets wrongly used for many quakes.
There are a few more recent and less commonly ones used eg Mww, Mwp, Me
Mw, the moment magnitude takes into account the length of the rupture, the area of the fault plane that has
slipped and this gives a better indication of the amount of energy released in the quake.
Mw can be calculated for any size event.
Dave
