It's all good. The earth is
just a bit restless this week. PMT maybe?
Seriously though. My opinion is that there are more than normal, and the news link I posted said it was felt in Darwin and apparently that IS unusual,
but they are always detecting quakes in the Banda Sea.
All 'international' quakes above 4.5 are measured by USGS in Mw (Moment of Magnitude) pretty much without exception.
'Locally' quakes use the Richter scale (ML). Some countries report numerous or all quakes in Richter, whereas for example Indonesia tend to report
in Mw as far as I can see. You may also see reports as Mb (Moment of body magnitude)
The Mercalli scale as you say measures the effect 'on the ground' so to speak and actually has no (direct) connection to the magnitude of the quake.
MMI is very much a consequence of terrain and geological structure and these features can magnify or diminish the effect considerably. These (S waves)
Rayleigh and Love waves (the more destructive of the two) are much worse than the body waves (P waves) which really are non-destructive and are the
precursors of the following destruction.
Every time I hear of a big earthquake anywhere on that archipelago I think of Toba and it's huge
supervolcano. Nobody seems to know for sure how close it is to another eruption, there are conflicting opinions, but the sheer amount of seismic
activity in that region makes me nervous.
Look out for a big quake in either Santa Cruz Cali or Baja. Most likely Baja but with all the shaking that has been going on their it seems to be
relieving its stress in a good way instead of one big bang.
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