Some of you may wish the details on these two events before I issue the day's
seismicity summary in several hours. This will be repeated in that summary, but
the early bird catches the worm - sometimes.

MODERATE (ML 6.0) EARTHQUAKE HITS OAXACA/GUERRERO, MEXICO
UNUSUAL EARTHQUAKE FOLLOWS IN NORTHERN WASHINGTON STATE (Ml 3.4)

SUMMARY

A moderate earthquake struck the central Mexico region near the
states of Oaxaca/Guerrero this morning. SSN (the local network out
of University of Mexico, Mexico City) gives this event a Ml 6.0
(NEIS preliminary MB = 5.2). Following are the parameters for
this event which was preceded by a series of light foreshocks:

O: 10NOV2001 17:09:09 15.5N 98.5W ML=6.0 SSN COSTA DE OAXACA , MX
O: 10Nov2001 17:09:18 16.2N 98.0W MB=5.2 NEIS NEAR COAST GUERRERO, MEX
O: 10Nov2001 10:49:00 16.1N 98.2W MB=4.6 NEIS NEAR COAST GUERRERO, MEX
O: 10Nov2001 10:38:58 16.2N 98.1W MB=4.6 NEIS NEAR COAST GUERRERO, MEX

For a list of Mexican earthquakes from SSN see:
http://www.ssn.unam.mx/SSN/ssn-ultimos.html

Hurricane Michelle had been expected to impact the seismicity
of this region. This forecast had specifically noted the influence
of a hurricane on this event as well. The magnitude was probably
affected by effects from Hurricane Michelle. This is the largest
earthquake in Mexico since a MB 5.5 (ML 6.1) earthquake about 200 km NW of
this epicenter on October 8, 2001. That event has had a strong
and long series of aftershocks in the Ml 3-4.7 range which is still
continuing at this time. No other events in Mexico have had Ml>=6
The region within 100 km of this epicenter has experienced 36
events of ML>=6 since 1899, about one every three years. The last
such event was a Mb 6.3 on Dec. 16, 1997.
This is the second event of M>=6 to hit the Central America region
in the past two days - yesterday there was a Mb 6.1 in the Caribbean
north of Panama/Costa Rica.

The Mexican earthquake was followed by an unusual earthquake slightly
more than an hour later in northern Washington state (Ml 3.4). This earthquake
had the following parameters:

O: 10NOV2001 18:30:59 48.9N 123.0W ML=3.4 PNSN N of Friday Harbor, WA

This is the first event of ML>=3 in Washington state since a Ml 3.0
in the Deming area on October 6, and the largest event in the state since
a Ml 4.3 near Olympia, WA on July 22, 2001.

This report had expected large global events to occur between 10-12 November
as reported on November 6:

"Strongest seismicity (i.e. events of Mw>6 and in this case probably
at least one event of Mw>7) is most likely to occur 4-6 days after the
storm commencement in the sub- or anti-solar regions or at high
latitudes. This would place these events around 10-12 November.
Enhanced seismicity in volcanic regions (Volcanos or volcanic arcs and
mid-ocean ridges) should also increase around November 10-12."

The Hurricane Michelle link had been examined in earlier reports
which stated:

" A possibly delayed seismic event from Hurricane
Michelle occurred tonight in the Costa-Rica/Panama region. This
earthquake measured Mw 6.0 and is the largest in North or Central
America since September when a Mw 6.1 occurred in Guerrero Mexico.
The seismic forecast from Michelle had stated on November 2:

" After landfall a moderate to strong earthquake is possible in either
the north or northeastern Caribbean subduction zone or in the
Mexican/Central America subduction zone."

and on November 1, this report noted regard Hurricane Michelle:

" Seismicity may increase along the Central America/Mexico subduction
zone with the Pacific ..."