Pacific-Antarctic Ridge (PAR) event of Sept. 2 and U.S. far-field aftershocks

The PAR event which occurred as M~6.4 on September 2 has shifted
the pattern of earthquakes occurring in the United States. Readers
may recall that after the New Zealand earthquake in late August, a
series of earthquake in the U.S. began to occur at 101-103 degrees
from that mainshock. Following the occurrence of the PAR event this
pattern changed so that the largest occurring quakes outside of
California in the contiguous 48 U.S. states began occurring at
101-103 degrees from the PAR event and away from the previous pattern.

The largest earthquake in the U.S. (outside Alaska and Hawaii and
excluding events in California and the Colorado swarm which was
at 102 degrees from New Zealand and continued past the PAR event)
that have occurred since the PAR event were the following:
02Sep2001 13:56:09 33.8N 82.4W LG=2.7 NEIS GEORGIA, USA
02SEP2001 19:33:48 44.4N 114.4W ML=2.7 MBMG W of Challis, ID
04SEP2001 01:59:05 44.5N 111.2W ML=2.6 UUSN SSW of W. Yellowstone, MT
05SEP2001 19:01:16 44.5N 111.2W ML=2.5 UUSN SSW of W. Yellowstone, MT
05SEP2001 03:55:39 44.7N 129.2W MB=4.0 NEIS OFF COAST OF OREGON
06SEP2001 21:40:44 45.8N 124.5W ML=2.9 PNSN NW of Tillamook, OR

YELLOWSTONE:

The Yellowstone earthquakes are part of a swarm of more than 50 which
began about an hour after the PAR earthquake.

All these events lie 101-103 degrees from the PAR earthquake epicenter.

GEORGIA:

The first of these events occurred about 4 hours after the PAR event
in Southern South Carolina or Northern Georgia. This Ml 2.7 earthquake
was the largest within 100 km of it's epicenter in about 5 years.
The far-field forecast had specifically mentioned northern Georgia
as an area where far-field triggering was likely.

IDAHO:

The Challis, ID earthquake is the largest in that area since Nov.
15, 2000. (Didn't Petra say something about Challis too?)

COAST OF OREGON

The event (Ml 4.0) off the coast of Oregon was the largest
within 100 km of that epicenter since Feb 7, 2000 when a Ml 4.3
was recorded.

TILLMOOK, OREGON
This is the largest event ever recorded within 75 km of this
epicenter. Three events larger than this have been recorded within
100 km of this earthquake - a Ml 4.9 on Nov. 8, 1960, a Ml 4.5 on Dec. 7,
1963 and a Ml 3.2 on April 6, 1990. The last event within 150 km of
this epicenter with Ml>=2.5 occurred on May 6, 2001 (Ml 2.5). The
last event larger than this within 150 km occurred on June 28, 2000 (Ml 3.1).
This earthquake occurred at 101.6 degrees from the recent Pacific
Antarctic Ridge (PAR) earthquake of 2 September 2001 at a distance
and in an area where far-field aftershocks were expected.

The far-field forecast from PAR (Post #9291 below from 9-2-01)
had stated that earthquake activity should increase in the following
areas:

"101-105 degrees***: No. Georgia, Yellowstone, Idaho, Oregon-Washington
Border area,"

The distance 101-105 degrees is the area where seismic energy
is concentrated at the edge of the shadow zone. The strongest
triggering of far-field seismicity is often seen in this zone.
and

Sources:
UTAH/YELLOWSTONE:
http://www.quake.utah.edu/req2webdir/recenteqs/Quakes/quakes0.html
IDAHO:
http://quake.wr.usgs.gov/cgi-bin/quake/mbmgsun.mtech.edu/name=quake/border=1
GEORGIA:
ftp://tanasi.gg.utk.edu/dist/JIEE/Events/00readme.txt
OREGON:
http://www.geophys.washington.edu/recenteqs/Quakes/quakes0.html
COAST OF OREGON:
http://wwwneic.cr.usgs.gov/neis/bulletin/bulletin.html