is there any short definition for it?
It is a measure of an earthquake's magnitude based on its seismic moment (a measure of the work done by the earthquake)
Moment magnitude scale
The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment (a measure of the work done by the earthquake).
what was the scale of 2005 qeshm earthquake? 5.8 where did it occur? Qeshm Island off Southern Iran any casualties because of it? 13 People were killed describe in few words the damage it caused? In Zirang, a village on Qeshm, 80 percent of the buildings were demolished. Seven villages experienced extensive damage, and 13 villages were destroyed what is the terminology for the scale which measures the intensity of an earthquake? Moment magnitude scale
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Moment magnitude scale [SEP] Introduction
The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment (a measure of the work done by the earthquake). It was defined in a 1979 paper by Thomas C. Hanks and Hiroo Kanamori. Similar to the local magnitude scale () defined by Charles Francis Richter in 1935, it uses a logarithmic scale; small earthquakes have approximately the same magnitudes on both scales. Moment magnitude () is considered the authoritative magnitude scale for ranking earthquakes by size.