posted on Dec, 30 2010 @ 09:25 AM
Originally posted by zenius
reply to post by muzzy
You have Mw Ms & Me. Aren't they all different? I don't know what they mean but would that have something to do with why your total is different to
Puterman's? Great job both of you for keeping score. I reckon the 2008 record will be blown easily. Do you go by UTC or GMT? We have less than 30
hours to go here.
Yes thats correct and will account for the difference.I have used the highest magnitudes for those lists. My project was/is to tabulate ALL quakes
above 7 regardless of the type of magnitude used. What the difference between Mw, Me and Ms is no one can answer in laymans terms, there is no easy
formula to convert them all to one type.
Some quakes that usgs put out have Ms as well as Mw but not enough that you can work out the difference and have a formula to convert all quakes. It
appears that different formulas are used for different regions, based on geology. What that means is that say a 7.5Mw in Iran may be a 7.2Ms, where as
a 7.5Mw in the New Hebrides Trench may be a 7.6Ms, just because Iran is landlocked and the NHT is a subdction zone and under the sea.
At the end of the day (or the end of the year) does it relly matter? if its a 7.3Ms (say for arguments sake in this case converts to 6.9Mw) it
wouldn't make the list as a Mag 7 according to usgs, but I challenge anyone who has been in a quake that size to tell me the difference in experience
between a 6.9 and a 7.2.
This is why there is argument to use more broad catagories for earthquake size, and hense the very minor/minor/ light/medium/strong/ very
strong/major/great descriptions for 2/3/4/5/6/7/8/9 magnitudes, but perhaps it should be very minor = 1.5-2.5/ minor = 2.5-3.5/light = 3.5-4.5/ medium
= 5.5-6.5/strong = 6.5-7.5 etc
As long as the type of magnitude is shown then people can draw their own conclusions.
On my research I discounted hundreds of 6.9 quakes over the 100 year time span, which theoretically should have been in there and classed as "very
strong" , which would have made the figures even more numerous per year.
edit on 30-12-2010 by muzzy because: (no reason given)