EXTREME GLOBAL AND REGIONAL SEISMIC QUIET CONTINUES,
BUT FLARE COULD CHANGE THAT

SUMMARY

Between eight and ten days following large global earthquake
which have extensive FFA sequences, a very quiet period often
occurs in global and regional seismicity. This was examined in
some detail in earlier daily summaries and reports and a discussion
on this board in September and October 2001. It has been
suggested that the strong triggering uses up immediately available
seismic energy in many areas of the world and that the length of
these strong quiet periods often extend from about 9 to about 18
days or more after the occurrence of large global events.
If that is the case, we could be in for a nice rest from
significant earthquakes in the next week (of course, the moment
that is said, Murphy's law takes effect and something unforeseen
happens).
On the other hand, a moderately strong solar flare did occur as this
report was being produced at about 01:40 UT on March 14. This flare
was class M7 to M8 and is the largest flare in several weeks.
It is possible that this will increase seismicity slightly
in the sub- and anti-solar regions - about 30W and 150E.
These regions include the Honshu/Kuril/Kamchatka group and
the New Britain/Solomon Is. to New Zealand in the south - subsolar.
The mid-Atlantic Ridge is located anti-solar to this flare.
A moderate (Mb5.0-5.5 event in the mid-Atlantic ridge is possible
within the next day and a Mb 5.5-6.5 is possible within 30 degrees
of 150E in the next two days - these generally occur at high
latitudes (>40 degrees latitude) or near the geomagnetic equator
(e.g. Solomon/New Britain region).

GLOBAL

NEIS recorded no earthquakes of Mb>5 today. While the average
per day at this range is about 3-4 such events there have been
none listed since March 11 (5.1). A Mb 5.0 did occur in the
Andaman Islands today, however. The most active area of the
world remains the Chile-Bolivia border region where a Mb 4.3
occurred today following an Mb 4.9 yesterday. Earthquakes of
Mb 4.9 also were listed in the North Atlantic Ocean and of Mb
4.5 southeast of Honshu Japan today.

U.S./CANADA

A second earthquake was recorded in the region of Oklahoma today
after the unusual series of events across the eastern U.S. and
Canada yesterday. This was a Ml 1.8 near the epicenter of yesterday's
Oklahoma earthquake.
Canada, Alaska, Hawaii and U.S. possessions recorded no events
of Ml>=3 today nor any significant microearthquakes.
For the second day in a row, the seismicity of the California/Nevada
area was extraordinarily low. One earthquake was recorded in the
Calexico swarm (Ml 2.5), the only event of Ml>2 in southern California
today. In Northern California, the Geysers area remained moderately
active with a Ml 2.6; a Ml 2.4 also occurred west of Parkfield this
morning.
The largest earthquake in the Pacific Northwest and mountain
states was a Ml 2.2 near Spokane, WA. This area became active
briefly last July and August (2001), but has been quiet again
for months, so today's event could be a reinitiation of that
swarm.

NEW ZEALAND

IGNS did not report parameters for any significant or felt
earthquakes today. Cultural noise continued on the on-line
seismometer, but no moderate quake traces could be found.

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 remained quiet today. No solar flares of
M- or X- class were observed.
A moderately strong solar flare did occur as this report was
being produced at about 01:40 UT on March 14. This flare
was class M7 to M8 and is the largest flare in several weeks.
It is possible that this will increase seismicity slightly
in the sub- and anti-solar regions - about 30W and 150E.
These regions include the Honshu/Kuril/Kamchatka group and
the New Britain/Solomon Is. to New Zealand in the south - subsolar.
The mid-Atlantic Ridge is located anti-solar to this flare.

Current parameters for this flare are not available.

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020313events.txt

TIDAL EFFECTS

March 16 is the second 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

Idaho MB>=1.0 15 1.9 0.05
New Zealand MB>=4.0 17 2.0 0.05
NW Europe MB>=4.0 9 2.0 0.05
So South America MB>=4.0 36 4.0 0.01
Central California MB>=2.0 7 1.9 0.05
Mammoth Lakes MB>=2.0 48 2.4 0.04
Mammoth Lakes MB>=3.0 26 2.9 0.01

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

Global MB>=6.0 -14 -2.3 0.04
Siberia MB>=4.0 -45 -2.4 0.04

TOMORROW IN EARTHQUAKE HISTORY

The largest two events to be recorded on this day (March 14)
were at the same two locations of the recent Mw 7.3 and Mw 7.3
in Hindu Kush and Mindanao. However, in both cases the events
were larger than the recent two.
One of the largest earthquakes to occur near Mindanao, Philippines
occurred on this day in 1913 (Mw 8.3). The event caused great
destruction, but loss of life was minimal. The following report
from Davao City Mindanao is from:

Series on Seismology, Volume IV, Philippines, by Lolita Garcia et al,
June 1985, Southeast Asia Association of Seismology and Earthquake
Engineering.

" ... very violent earthquake from SE-NW, which lasted from four to
five minutes. Before the first movement there were subterranean
noises from the SE which lasted two minutes. Pendulum clocks were
stopped and bottles and other objects fell from the shelves in the
houses, bells rang, and fissures were opened up, from which water
and fine sand came. The debris fell to the SE. Several walls in the
church and convent were thrown down, while in the town, the palm
thatch houses rocked a good deal and many of them remained out of
plumb; crockery was broken in all of them. 'This earthquakes is a
sever one; from the beginning I observed some of the oscillations
and movemtns of the church and convent to be so large that it was a
marvel that they were not brought to the groudn. Not being able
toi remain upright, I knelt down but even so I could not keep still,
so I lay down on the ground till the vibrations ceased, which
appeared to me to be about two minutes. The earthequake seemed to
be entirely oscillartory, without vertical shocks, which was the
reason so little damage was done.' (Rev. R. Poruga, S.J., Davao)"

A slight tsunami was generated in lakes and rivers. The earthquake
was not so notable for it's damage but for it's duration. Most
buildings are built to withstand horizontal forces and did not
come down when the motion was mostly horizontal. It is vertical
motion combined with horizontal that usually levels buildings.

The Hindu Kush earthquake on this day was a Mw 7.8 and occurred
on March 14, 1965. Because of the great depth of this event (about
219 km) little damage was done on the surface. This is quite
typical of many large earthquakes in Hindu Kush. The event on
March 3, 2002 was atypical in that it did considerable damage
and was said to have killed more than 100.

The only other deadly earthquake on this date occurred in
Mexico in 1979. This Mw 7.6 killed 5 and caused severe damage
throughout the Guerrero state. Slight damage was also suffered
at Acapulco and Guadalajara, Monterrey and Puebla. This Mexican
earthquake was followed slightly more than a day later by
a swarm of earthquakes in the Lander's region of southern California
in the Homestead region. Theese earthquake started with a Ml 4.9
and built to a maximim size of Ml 5.7. A strong aftershock
sequence lasted for more then two days. The distance between
the Mexican and the subsequent So. California event is approximately
19 degrees, a distance where some believe Far-field triggering
is prominent. Were the events in So. California triggered by
the Mexican earthquake the day before - anybody's guess.

U.S./CANADA

The strongest activity in the U.S. on March 14 continued to be
in the Central and eastern Andreanoff Islands. Strong earthquakes
occurred in this region of Alaska as aftershocks in 1957 (Ms 7.5);
1979 (Ms 5.3); 1987 (Mb 5.2); 1991 (Mb 5.9); and in the Fox Islands
in 1995 (Mb 6.3) and in 1996 (Mb 5.3).

The only damaging earthquake in the contiguous 48-states occurred
as a Mb 5.0 in northern Montana in 1947. This event cracked plaster
which fell to the floor at Seeley Lake where hanging objects
swung and buildings cracked and rattled. Five miles to the east
persons in a log house though a heavy gust of wind had caused the
building to shake.