LARGE EARTHQUAKE (MS 6.3 (GSSC)) HITS KERMADEC ISLANDS

SUMMARY

The strongest event of the day was a Ms 6.3 (GSSC) in the region
south of the Kermadec Islands. A moderate earthquake of Ms 5.3
also hit north of this epicenter in the Central Kermadec Islands
on 14 September. The Ms 6.3 was followed less than 3 minutes later
by the second largest earthquake today - a Mb 5.0+ in the Hokkaido/
Kuril Island region. Both earthquakes followed a moderately
strong M5.6 class solar flare by about 30 minutes and were nearly
sub-solar at the time of the flare.

GLOBAL

Other seismic activity today occurred in Central Asia in the
region of Southern Xinjiang, China (Mb 4.9-5.0). Earthquakes of
this size in this area often cause damage and injuries. GSSC
also recorded a Ms 3.7 (probably Mb about 4.5) in the northern
Kuril Islands this afternoon (UT). NEIS is now giving a Ms 5.3 to
the earthquake in southern Greece this morning (see yesterday's
report for details). This would make it the largest earthquake
within 100 km of this epicenter since Nov. 18, 1997 when a Mw 5.3
also occurred as an aftershock of an Mw 6.5 on October 13, 1997.

U.S./CANADA

It was another quiet day in seismicity throughout the U.S./Canada
region. No events of Ml>=3 were recorded in the contiguous U.S.
for the 6th straight day, making this one of the longest periods
without such an event in the past three years.
The largest earthquake in the general vicinity of the U.S.
occurred in the Gulf of California (Mb 4.2). Hurricane Ivo
has been moving along the coast of Baja California for the past
week and may have helped trigger this event. Only three events of
Ml>=2 have been reported in the California/Nevada region today -
both in the Salton Sea area at Brawley (Ml 2.1) and Ocotillo Wells
(Ml 2.3). A Ml 2.4 also occurred near Parkfield this afternoon.
Expect this quiet period to end in the next day or two.
Most local networks were not reporting over the weekend. Two
events of Ml 2.4 and 2.6 were reported in the Jackson Lake region
of Wyoming by the USBR, however and were the largest events reported
in the lower 48 states today.
The swarm of events at Mt. Hood, OR continued with a microearthquake
of Ml 2.1 this morning. Seismograms from TDH (Tom, Dick and Harry
Mountain) show about 15 additional microearthquakes at Mt. Hood
today which PNSN will report on Monday.
No earthquakes of Ml>=3 have been reported from Alaska (AEIC) or
from Hawaii (HVO) today.
The swarm south of Vancouver continued to decline in intensity
today. No light or moderate events were registered on local
seismograms over the past 24 hours.

NEW ZEALAND

A strong earthquake occurred in the Kermadec Islands on 16
September. GSSC is giving this Ms 6.3, however it appears the
final magnitude will be considerably smaller. No other events
were reported from the region in the past 24 hours. The on-line
seismometer shows several local events of M>3.

The IGNS on-line Seismometer can be found at:
http://www.gns.cri.nz/news/earthquakes/latest_drum.html

GEOMAGNETIC/SOLAR FIELDS

The geomagnetic field has remained quiet throughout the day (September
16, 2001) despite a moderately strong solar flare of M 5.6 class.
The parameters of this flare follow.

Flare # START MAX END CLASS
4250 + 0339 0353 0418 M5.6

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20010916events.txt

No significant seismicity was recorded during this flare, however
earthquakes of Ms 6.3 in the Kermadec Islands and of
Ms 5.0 in the Kuril Islands occurred within 30 minutes of the
end of this flare. The Kurils were approximately sub-solar
at the time of this flare.

TROPICAL STORMS

Tropical Storm Gabrielle is now off the coast of North Carolina
and moving into the Atlantic ocean. No further effects from this
storm are expected in North America. See:
http://www.wunderground.com/auto/HurricaneSite/tropical/tracking/at200108.html

Hurricane Felix is slowing and weakening in the Central Atlantic.
It is expected to hit the Azores on Tuesday as a Tropical Storm.
See:
http://www.wunderground.com/auto/HurricaneSite/tropical/tracking/at200107.html