reply to post by westcoast
Well technically, Olivine is right- this quake occurred on the Queen Charlotte, north of the scientifically defined CSZ, which supposedly ends at
Vancouver Island. So yeah, technically the title of the thread is a little off. But go ahead and ask Mother Nature if she cares what we call it when
the whole thing gives way the next time.
The Queen Charlotte fault intersects, and really is the northern extension of the CSZ. And fault extensions proved to be quite nasty in Japan with
that 9+. I guess I think of it more in terms of the whole plate intersection, up and down the coast, without so much emphasis on the names given by
As to the types of motion, it might help to review some links about focal mechanisms, characteristics of the Queen Charlotte Fault, and previous
quakes that have occurred there. For the more technically inclined, you can view the historic moment tensor solutions here:
But I think because this occurred in a subduction zone, it is considered a type of thrust event, which is then further defined by the particular type
of slip motion on the fault.
Earthquake Canada says the first quake is likely associated with "relative motion across the Queen Charlotte fault system offshore" of the BC
coast. The agency says the surrounding area of that plate boundary has hosted eight earthquakes of magnitude 6 or greater over the past 40-years. It
also notes, the quake, "is related to that Haida Gwaii earthquake three months previously, and is an expression of deformation along the same plate
So at least one agency is relating this to the last one. Stress redistributions we talk about that happen because of big quakes occur in areas
adjacent to the epicenter- and north and south of the epicenter along the fault line- which can manifest as quakes in the future. And here is a
textbook example of this, with this quake occurring north of the last Haida Gwaii quake.
One view might have it that this quake is a distributed stress relief reaction to the Haida Gwaii quake, while another view might have it that is its
My view is that it's too many damn quakes on that zone, as I have been saying for some time with the other thread!
Yeah that one:
edit on Sat Jan 5th 2013 by TrueAmerican because: (no reason given)
And oh, for those looking for the latest status of movements on the fault, yeah, she's still moving, generating all kinds of small aftershocks, most
unreported. I am back to live monitoring again, after taking a break.
edit on Sat Jan 5th 2013 by TrueAmerican because: (no reason