posted on Mar, 15 2012 @ 01:15 PM
Originally posted by westcoast
reply to post by geotrician
You are hiting right on what I have been hedging around for awhile now on some of my other threads, but I haven't worded it so well. Based on
your hypothesis, you should take a look (if you haven't already) at the Vancouver Island region. Perhaps back to the recent 6.4 quake there (sep 9th
2011).
The tremors are again clustering there.....I expect to see another off-shore quake in the region soon. I am trying to stay away from predictions
here, but really don't see this as one, but rather a tie-in to your hypothesis. You may not agree with me though, if I am interpreting you wrong.
I will try to give my answer to this but JV is the guy to ask. And it is pretty quiet now, so I will chime in. The 2011 M6.4 event occurred where the
effective northern extremity of the Juan de Fuca plate goes under Vancouver Island as defined by the Nootka fault. This seems to be a repeating
pattern with several quakes in the 2.0 to 5.0 range, followed by a M6 at this same point. If this is true (I only have looked at post 2000) then it
clearly expresses the stress buildup where the northern margin of the plate passes under the thick exotic terrane of Wrangellia under central
Vancouver Island. I don't think it is related to the tremor patterns except that the tremor patterns usually have died out before this part of
Vancouver Island is reached. Here is a comparison of two of the central VI/plate boundary earthquake patterns. The one of the left is for 2000-2006
and ends with a M6.4 right up against the VI boundary. And of course the Sept. 2011 M6.4 is in almost the same exact place. So I doubt it means
anything in regards to an upcoming megaquake.

edit on 15-3-2012 by geotrician because: added phrase
And to illustrate the extent of tremor under Vancouver Island (constrained by the sensing instruments) here is a tremor plot for 2005-2012:
edit on 15-3-2012 by geotrician because: added figure