MODERATE TO LOW GLOBAL SEISMICITY LEVELS CONTINUE

SUMMARY

Moderate to low levels of seismic activity occurred over
most of the earth today. The largest earthquake was a Mb 5.5
in the Banda Sea region. The Banda Sea is located near the
geomagnetic equator. A moderate geomagnetic storm occurred this
morning (UT) while the region within 30 degrees longitude of
150E was sub-solar including the Banda Sea event. A M1.0 Solar
Flare also occurred at about 11:00 UT while regions within 30 km
of 165W were anti-solar. Shortly after the M1.0 flare (about an hour
later) a series of moderate earthquakes began in the southern Alaska
area which was antisolar at the time. The first of these was Mb 3.8,
maxmimum was Mb 4.5. All events recorded by NEIS and other teleseismic
networks today of Mb>=4.2 lay within a longitude band where
effects from these two geomagnetic events would have been
maximized (125E to 145W).

GLOBAL

Earthquakes listed by NEIS today included the largest in
the Banda Sea this evening (Mb 5.5); the Alaska group (Mb 4.5, 3.8..)
a series in the Fiji Islands (Mb 4.9, 4.6, 4.1); two in the
Volcano/Bonin Islands south of Honshu (Mb 3.6, 4.9) and
a Mb 4.1 in the Gulf of California this evening (UT). NIED
is also listing a Mj 4.8 off the southeast coast in the last
several hours.

U.S./CANADA

Two light to moderate earthquakes occurred in the U.S. and
bordering areas today - a Mb 4.1 in the Gulf of California
south of the current Calexico/Baja swarm; and a Mb 4.5 in
southern Alaska near Anchorage which was followed by a Mb 3.8.
AEIC issued a press release for this event which can be found
on the web at:

http://www.aeic.alaska.edu/Seis//Input/mitch/frame2html/frame2html/results//20020319173216_.pdf

The second light earthquake occurred in the Gulf of California
south of the currently active Calexico/Baja swarm in an area
which has not seen much activity for some time. The last Ml>4
event near today's epicentral region occurred on Jan 16, 2001.
Only 3 such events have occurred nearby in the past three years.
Seismicity in the rest of California/Nevada today, however, was
extremely low. Only three events of Ml>=2 have been listed - one
each in northern and southern California. These occurred as a Ml 2.4
near Fairfield, northern California, a Ml 2.0 near Bodie NV (a reported
Ml 2.4 in northern Nevada is a ghost event and is a falsely
identified teleseimic arrival from Banda Sea), and near Yorba
Linda (Ml 2.2) in southern California. No events of Ml>=2 were
identified in the Calexico/Baja swarm today. An Ml 1.7 was
also observed near Coalinga.
The most unusual earthquakes of the day occurred in New Jersey
(Ml 0.8). This is the first event in this region since October
2001 shortly after the Trade Towers collapsed. That event occurred
in upper Manhattan, N.Y (Ml 2.6) slightly to the southeast of
today's epicenter. The last confirmed earthquake in New Jersey
occurred on Jan. 17, 2001 (Ml 2.4).
The other unusual earthquake in the U.S. was a Ml 2.9 in northwestern
Colorado. It was felt slightly in the epicentral region.
This is the largest earthquake within 50 km of this epicenter
since a Ml 4.4 on Jan 30, 1976, 26 years ago. A Ml 2.8
occurred in this region on March 8, 1994. Earthquakes of Ml 5.7
and Ml 3.7 were recorded in May 1973 and August 1963 in this
region respectively.
A minor series of very light (Ml about 2) events has been
occurring in the Yellowstone region over the past two days, and
several Ml>=2 earthquakes have also occurred in the Montana
region today - one near Seely Lake was Ml 2.3.
PNSN recorded three earthquakes in the ML 3+ range off the coast
of Oregon and California in the past two days, but as usual,
these epicenters are subject to revision. No significant earthquakes
(Ml>=2) were listed by GSC today in Canada.

NEW ZEALAND

Seismicity in the region of New Zealand appeared to calm down
today after moderate activity off the east Coast North Island
and in the Kermadec Islands yesterday. IGNS did not issue any
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

There was a moderate geomagnetic storm today which began at
about 02:00 UT. This storm lasted only 6 hours. A seismic
watch is normally issued if a storm of this size lasts for
at least 9 hours. Small increases in seismicity may occur
within 30 degrees longitude of 150E over the day after this
storm. Most listed events today did lie in this longitude range
so some triggering may have been occurring.
A M1.0 class solar flare occurred between 11:06 and 12:31 UT
this afternoon. This flare erupted while 165W longitude was
anti-solar. Within 45 minutes of the flare, a Ml 3.8 foreshock
occurred in southern Alaska, followed several hours later by
an Ml 4.5. The epicenter was near the anti-solar point at the
time of the flare and some flare effect may have been occurring
here.
The parameters of this flare follow:

FLARE # START MAX END CLASS

3000 + 1106 1144 1231 M1.0

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020319events.txt

TIDAL EFFECTS

March 22 is the eighth day after the beginning of the new 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

Pacific-Antarctic Ridge MB>=4.0 58 2.0 0.05
Central So America MB>=4.0 23 2.3 0.04
Mt ST. Helens MB>=0.0 40 3.0 0.01
Mt ST. Helens MB>=1.0 55 4.1 0.01
Washington MB>=3.0 19 3.3 0.01
JMA MB>=4.0 14 2.0 0.05

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

Siberia MB>=4.0 -37 -2.0 0.05
East US MB>=1.0 -12 -2.3 0.04

TOMORROW IN EARTHQUAKE HISTORY

GLOBAL:

The worst seismic catastrophe ever to hit the country of Argentina
occurred on March 20, 1861. This earthquake (Mw 7.1) caused massage
destruction and loss of life in Mendoza, Argentina. Estimated losses included
11,978 persons were killed. Destruction in the area was instantaneous
and wide spread through the entire city of San Vicente. In the annals
of the city of Los Andes, among the casualties were 1,583 children
including nearly half the residents of the city.

The most unusual earthquake of the day occurred in 1966 at Kichwamba
and Bondibogyo, Uganda (Mw 7.0). This earthquake is the largest and
most destructive earthquake ever to be experienced in that country and
one of the most destructive in African history. The damage was centered
about Bundibugyo, a one-street township about 42 miles from Fort Portal,
near the congo border. About 140 fatalities and hundreds of injuries
were reported from Bundibugyo Fort Portal and Kichwamba. At Kamango, in
the Congo, a chasm 9 feet wide and 1,000 feet long opened up in the
ground. Immediate relief measures were greatly impeded by landslides
which severed communications and blocked highways.

U.S./CANADA

The largest earthquake in the U.S./Canada region on this day
occurred in 1999 in the Central Andreanoff Islands (Mw 7.0).
The other largest earthquakes on this day in this region also
occurred in the Andreanoff Islands (1968, Mw 6.5), (1972, Mw 6.0);
(1975, Mw 5.5). None of these were damaging to the sparse local
population.

The strongest earthquake on this day in California was an
aftershock (Ml 5.0) of the Northridge earthquake. This aftershock
shook down several structures which had been weakened by the
Northridge earthquake two months earlier on MLK day in January, 1994.

The most unusual event occurred on March 20, 1950 (Mb 5.0) near
Lassen Peak and Shasta Dam in northern California. The event was
felt over about 5,000 sq. miles and extended from Hat Creek to
Susanville, Sacramento and Shasta Dam. Scattered reports of felt
effects came from Nevada as well.