THE LACK OF EXCITEMENT IN TODAY'S SEISMICITY - COULD CHANGE

SUMMARY

There was little newsworthy in the day's seismicity. No moderate
or large earthquakes have occurred since last report. Areas which
were active remained active today. A strong geomagnetic storm which
began between 00:00 and 02:00 UT may bring help in bringing
out some additional seismicity however. This is the first strong
geomagnetic storm since a brief storm on March 6.

GLOBAL

The strongest earthquake today was the Mb 5.5 in northern Chile
reported on last night. Other events of Mb>=4 apparently occurred
in the Leeward Islands (Mb 4.4); the Andreanoff Islands (Mb 4.7 and 4.7);
New Britain (Mb 4.8); Southern Sumatera (Mb 4.5) and Taiwan (Mb 4.4).
CSEM has listed several unconfirmed events as well.

U.S./CANADA

Alaska saw the most and strongest activity in the U.S./Canada
today with two Mb 4.7's in the Andreanoff Islands and a Ml 3.3
and 3.0 inland. No events of Ml>=3 were reported from Hawaii.
Only five earthquakes of Ml>=2 were located in California making
this a very quiet seismic day for that state. In northern California
such events occurred north of the Geysers (Ml 2.4) off the coast
from Eureka (Ml 2.4) and near Pacifica in Central California (Ml 2.5).
It was even quieter in southern California where one event was
listed in the Calexico swarm (Ml 2.8) and one was listed near
Corona east of Los Angeles (Ml 2.2).
No events have been listed with Ml>=2 in the rest of the U.S.
or Canada as having occurred today. A Ml 1.9 near Maine was the
most unusual new event listed today.

NEW ZEALAND

After a flurry of activity off the east coast of North Island
yesterday, it was relatively quiet earthquakewise in New Zealand
today. IGNS has not issued any new earthquake parameters today.

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

GEOMAGNETIC/SOLAR FIELDS

The earth was hit by several moderate periods of geomagnetic storminess
today at 13:23 Ut and again at about 18:00-18:21 UT. Neither of these storms
was particularly strong.. However, there was a sudden shift in Hn field
nearly doubling it's intensity within 1-2 minutes (GOES) with
the first. The sudden commencement can be observed on seismograms from
Yakutsk, So. Karori, New Zealand, the South Pole and VNDA. A strong
Geomagnetic storm did hit about 03:00 UT on March 19, however.
If this storm persists for 9 hours a seismic watch will automatically
Go into effect for areas at high latitudes, along the geomagnetic
Equator and within about 30 degrees longitude of 30W and 150E.
This area includes much of the western Pacific seismic zone, and
The mid-Atlantic.

There were no M- or X-class solar flares listed since last report.

Flare # START MAX END CLASS

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020318events.txt

TIDAL EFFECTS

March 21 is the seventh day after the beginning of the lunar month.
Regions most likely to experience tidal triggering
on this day (With associated magnitude ranges; the percent change in
seismicity rate over background seismicity rate on this
day of the lunar month; statistical z-value and
significance level) are:

Region Magnitude range %change z-value Significance level

No Regions

Regions expected to experience reverse triggering (i.e. they are
unlikely to experience a significant event at this period of the
lunar cycle) are:

Region Magnitude range %change z-value Significance level

East US MB>=1.0 -13 -2.5 0.03

TOMORROW IN EARTHQUAKE HISTORY

The largest earthquake (Mw 7.9) to be listed on March 19 occurred in
1952 in the Central Philippine Islands. This earthquake was felt at
Bhutan City where the intensity was largest. The only known structural
damage was cracs in one of the walls of the town church. A two- by
three-meter section of the wall fell and proke some of the church
pews.

The most damaging earthquake on this date in history occurred in
1984 in hte Uzbekistan area. This Ms 7.1 injured at least 100
people and caused extensive damage in the Gazli area (MMI XI).

An Ms 7.1 did some minor damage to buildings in the region
of West Irian, Papua New Guinea on this date in 1995.

U.S./CANADA

Aftershocks of the great Andreanoff Islands earthquake of
1957 continued on this date with a Ms 6.8, but the most
damaging event on March 19 in the U.S. and Canada occurred
in 1954 when a Ms 6.2 hit in the Santa Rosa mountains of
southern Califonria. This event was felt over approximately
40,000 square miles of southern California and portions of
southwestern Nevada and western Arizona. There were many aftershocks.
In many areas groceries, vases, and small objects were knocked
from shelves. In some areas glass was broken. At Coachella
many were frightened. Pendulum clocks stopped and many objects
fell from shelves. Near panic was reported at the local
prison as the jailhouse rocked (could this be the origin of
the song "Jailhouse rock" which was written about the same time?).
The earthquake occurred at 01:54 a.m. Police report that
bedroom lights snapped on throughout the county after the
quake. At Oasis, north of Coachella a concrete surface irrigation
pipe broke. At Palm Springs a water pipe broke to a hotel, and
several swimming pools were cracked. A parked truck started
rolling and caused an unmanned collision. San Bernardino
suffered a temporary power blackout as two lines swung together.
Cracks were reported at City Hall. No one is known to have been
injured or killed in this earthquake.