Received the following this evening. I might add that several areas in this
forecast might be of interest to readers of this board including the fact
that the region near Nicaragua/Costa Rica/El Salvador is near the antipode
of this earthquake and likely to experience far-field aftershocks. The
forecast for the U.S. is not strong, but does include the area of southern
California from L.A. to Arizona where there has been an increase in activity
over the past week.

Lowell

AFTERSHOCK FORECAST FOR SOUTH INDIAN OCEAN M ~6 QUAKE SEPT 7, 2001

An earthquake occurred tonight in the Indian Ocean south of
Sumatera. The current parameters for this event are (NEIS):

2001/09/07 02:45:58.5 13.3S 97.2E 10G Mb6.4 M NEIS SOUTH INDIAN OCEAN

No earthquakes of Mw>=6 have ever been located within 300 km
of this event in teleseismic catalogs.
This earthquake would not be expected to have a substantial
far-field aftershock sequence because of it's moderate size.
However, due to it's unusual location, some unusual far-field
triggering IS expected to occur. Areas which might see a slight
increase in seismicity follow.

Following is a preliminary far-field forecast from this event.
Areas within 36 degrees are expected to see maximum magnitudes increase
by 0.2-0.5 units, at distances farther than this, increases in
maximum magnitude are expected to be about 0.3 units or less.
Seismicity is expected to increase in these areas for the next
7 days (i.e. through 14 September, 2001)

0-5 degrees: (Classical aftershock zone)
9-10 degrees: South of Java (about 7S 106-108E, this area has
had two moderate events in the past several days and more may
be expected). Southern Sumatera (around 5S 97E)
17-19 degrees: Sumbawa Island, Northern Sumatera (2-4N 95-97E)
34-36 degrees: Halmahera, Moluccas, Mindanao, Philippine Islands
Myanmar (about 19N 99-100E)
43-45 degrees: Taiwan (23N 122E), Nepal/Tibet (32N 87E),
West Irian (2S 139E)
59-61 degrees: Tokyo, Japan (36N 142E); Solomon Islands (10S 161E),
Hindu Kush/Afghanistan (37N 72E), Ethiopia (Afar triangle) (11N 40E
or 12N 44E); Macquarie Islands (63S 148E or 52S 160E)
71-73 degrees: Wellington, Cook Strait, New Zealand (42S 175E or 40S 174E)
Southern Kuril Isl. (44N 146E), Fiji Islands (16S 178E)
101-105 degrees***: Unimak Island Alaska (54N 164W), Andreanoff Isl.
(51N 174W), South Sandwich Islands (60S 26W)
142-146 degrees: Southern California (116-119W), Central Utah,
NW Colorado, New Brunswick (49N 66W), Canada, Chile-Peru border (17-19S, 71W)
176-180 degrees: The exact antipode is at 13.2N 82.8W an area in
the Caribbean off the coast of Nicaragua. Seismicity should
increase in the Nicaragua/Costa Rica/Panama area with a possible
event in the Mb>5.5 range in the next 7 days.
Most likely areas to be affected are 101-105 degrees distance and
at 142-146 degrees away from the epicenter.

Previous history

Since this is the first earthquake in this size range ever recorded
in it's general epicentral region, there are no historical precedents
for following seismic activity.