SHARP INCREASE IN SEISMICITY FOLLOWS ANDREANOFF MS 5.9 EARTHQUAKE/M5.6 FLARE

SUMMARY

Seismicity increases were recorded in many regions of the world
today, but were most notable at high latitudes following a strong
solar flare (M5.6) at 01:35 UT this morning and a subsequent Mw 5.9
earthquake in the Fox Island, Alaska. The flare occurred while the
region within 30 degrees longitude of 158E was sub-solar and the
region within 30 degrees of longitude 22W was anti-solar. This
included regions of the Andreanoff Islands to the Kurils and the
Tonga Islands to New Zealand. All events listed by NEIC with
Mb>4.2 today lay in this longitude band including three in the
Andreanoff Islands; a Mindanao aftershocks (Mb 5.0); the
Tonga (Mw 5.0), Kermadec (Mb 4.7), and No. Kuril (Mb 5.5-6)
events; and earthquakes in the Mariana Islands (Mb 4.1) and
southeast of Honshu (Mb 4.3).
Five hours after the flare the first of two foreshocks occurred in
the Andreanoff Islands (an area at high latitude within the specified 30
deg. longitude range). These events were of Mb 4.6 followed an hour later
by an Mb 4.4. These foreshocks were followed 16:08 UT by a Mw 5.9 earthquake
in the Fox Islands, Aleutians.
This was the largest earthquake to occur in the Aleutian Islands
since an Mw 6.0 on July 7, 2000. It is the largest in the eastern
Aleutians since a Mw 6.4 on Jan 28, 1999.
A series of small shocks in the central and eastern U.S. had
preceded this earthquake in the previous two days as had been
noted in this report. There have been several occasions in the
past when a large earthquake in the Andreanoff Islands. Following
are some cases:

1986 - Andreanoff Earthquake on May 7 (Mw 8.0) preceded by:
---> 2 hr. earlier earthquakes in So. Ontairo (Ml 2.5, 1.7)
---> May 7 (20 hours earlier) - Tuscaloosa, Alabama Mb 4.8
---> May 6 (about 1.3 days earlier) _ Rhode Island Ml 1.9
---> May 6 (about 1.5 days earlier) _ New Madrid Ml 1.7
---> May 6 (about 1.5 days earlier) _ East of Maine Ml 1.6
---> May 5 (about 2.0 days earlier) _ North of Maine Ml 2.2
---> May 2 - Chesapeake Bay/Pennsylvannia Md 2.5
---> April 29,30 Central Oklahoma Ml 2.0, 1.9

1996 - Andreanoff Earthquake on June 10 (Mw 7.9) preceded by:
---> June 9 (about 1 and 5 hours earlier) Quebec (Ml 1.8, 1.4)
---> June 8 (about 1.2 days earlier) New Hampshire Ml 2.8
---> June 8 (about 1.3 days earlier) So. Ontario (Ml 2.8, 2.0)
---> June 7 (about 1.5 days earlier) Kentucky/Illinois Ml 2.5
---> June 7 (about 1.5 days earlier) Quebec (Ml 3.0)
---> June 7 (about 2 days earlier) New Madrid (Ml 1.3)
---> June 6 (about 2 days earlier) New Brunswick (Ml 3.0)

1965 - Rat Island Earthquake on Feb. 4 (Mw 8.3) preceded by:
---> Feb 4 (about an hour earlier) Central Colorado (Ml 1.5)
---> Feb 3 (about an 7 hours earlier) Texas (Ml 3.3)
---> Feb 3 (about a day earlier) New Mexico (Ml 2.9)
---> Feb 3 (about a day earlier) Southern Ontario (Ml 2.8)

1964 - Good Firday Earthquake on March 28 (Mw 9.3) preceded by:
---> Mar 28 (about an hour earlier) South Dakota (Ml 4.3)
---> Mar 27 (about an hour earlier) W. Colorado (no magnitude)
---> Mar 27 (about 12 hour earlier) E. Colorado (Ml 2.5)
---> Mar 24 (about 4 days earlier) South Dakota (Ml 4.3)
---> Mar 24 (about 4 days earlier) New Brunswick (Ml 2.8)

1957 - Central Andreanoff Earthquake on March 09 (Mw 8.3) preceded by:
---> Mar 07 (about 1.5 days earlier) West Virginia (Ml 2.9)

In all cases these represent a substantial increase in regional
activity over the previous 10 days.
It seems possible from these examples that in preparation for
great earthquakes regional straining occurs which is manifest in
small earthquakes throughout a large area.
Based on these types of data, when the string of small earthquakes
in the central and eastern U.S. began two days ago this report
suggested a large event might be imminent. The daily report from
12 March had stated:

" There have been occasions in the past, most notably prior to the
great Alaska earthquake of March 28, 1964, when a series of aligned
earthquakes occurred prior to a great earthquake at an FFA distance
to that event.... Generally these alignments of quakes
in the eastern U.S. appear to presage great events by no more than
2 days, but there are also cases where no great event follows."

The Andreanoff Island event also may have been affected by Far-field
triggering action from Hindu Kush and from Mindanao. The FFA forecast
from both had noted:

"Areas of U.S. and Canada where triggering may occur (Ml>=3.5)

Rat Islands , Andreanoff Islands"

GLOBAL

In addition to the strong earthquake in the Andreanoff Islands,
moderately strong earthquakes also occurred today in the northern
Kuril Islands (Mb ~ 5.5 to 6) and in the Tonga Islands (Mb 5.5).
Both of these location are within the 30 degree longitude band
of sub-solar sites. The event in the Kurils had been anticipated
in yesterday's report from the M5.4 solar flare yesterday.

"... 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 ..."

This event had also been anticipated as a FFA from both Mindanao
and Hindu Kush as noted in the FFA forecast:

"The most likely location for a large earthquake in the next 10 days
appears to be off the East Coast of Honshu northward to Kamchatka and the
Kuril Islands. There are few occasions when a large event in Hindu Kush is
not followed by a strong earthquake somewhere between Honshu and the
Komandorsky Islands. Often there is a series of such events along this arc."

This was followed up on in the FFA forecast from Mindanao:

" The most likely location for a large earthquake in the next 10 days
appears to be in the Central to Northern Kuril Islands. This area
was also on the Hindu Kush FFA list, and has a record of very
strong activity following events in Mindanao. A Mw 6.5+ is possible,
with about 0.5 probability in the next two weeks in this general
region."

and

"The most likely events of Mw>=6 in the next 10 days appear to be:
(Number in paranthesis indicated number of times and event of M>=6
has followed a Hindu Kush mainshock within 2-3 weeks).

Northern Kuril Islands (5)
Two great (Mw>8) shocks appear to have occurred in the central
and northern Kurils after large Mindanao events. Several other
large events have also been associated within several weeks."

The Tonga Islands, where a Mb 5.4 event occurred this morning,
lie near the geomagnetic equator, another area where flare effects are
enhanced.

U.S./CANADA

Seismicity also increased in the region of California today where
a quiescent period had been in effect for the last several days.
Two events of Ml>=3 (in the Hector Mine aftershock zone (Ml 3.3)
and near the northern Coast near Willow Creek (Ml 3.1) occurred today
as well as a Calexico/Baja aftershock of Ml 2.9. There were 4 aftershocks
recorded in this region of Ml>=2 after two days on no such events.
The Mammoth Lakes region also continued to see moderate seismicity
with events of Ml 2.2, 2.3 and 2.2 throughout the day. The only other
event in the area of Ml>=2 occurred north of the Geysers near
Lakeport.
No events of Ml>=2 were listed from the Pacific northwest, however
late this evening a Ml 2.0 was recorded in southern Canada north
of Montana. A minor swarm is continuing at the high 1Ml to low 2's
in the Yellowstone region.
A third earthquake (Ml 2.4) was located by TUL in Central Oklahoma today,
the largest in a series of such events that began with a Ml 2.2 on March
12, 2002. Today's occurred several hours before the Andreanoff Isl.
Mw 5.9 and the series is the first events recorded in Oklahoma
since Feb. 8.
No events of Ml>=2 were recorded in Canada today, however, a Ml
3.3 was listed as occurring on March 13 in the Vancouver Island
area.

NEW ZEALAND

The moderate swarm in the northern Kermadec Islands continued
today with a Mb 4.7 this morning following the M5.4 solar
flare about two hours earlier. The Kermadec Islands are also
located in the sub-solar longitude band where effects were considered
possible from this flare.

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, however there was a
moderately strong solar flare of class M5.7 which occurred
early this morning and may have affected seismicity in the sub-
solar regions (see above discussion).
The parameters of this flare were:

Flare # START MAX END CLASS

1410 0138 0144 0242 M5.7

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020314events.txt

TIDAL EFFECTS

March 17 is the third 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

Alaska MB>=4.0 6 1.9 0.05
Central California MB>=2.0 9 2.3 0.05
Mammoth Lakes MB>=2.0 45 2.3 0.05
Mammoth Lakes MB>=3.0 23 2.6 0.03
Mt ST.Helens MB>=1.0 29 2.2 0.05
Spain MB>=4.0 31 2.2 0.05
Arctic MB>=4.0 36 2.3 0.04
Caribbean MB>=4.0 27 3.0 0.01
Caucasus MB>=4.0 23 2.9 0.01
So. California MB>=0.0 10 2.7 0.03
So. California MB>=2.0 22 1.9 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

No Regions

TOMORROW IN EARTHQUAKE HISTORY

GLOBAL

The strongest and most damaging earthquake on this date occurred
in south-Central Chile on March 15, 1657. This event caused severe
damage throughout the Conception/Penco region and resulted in
at least 100 killed. The quake, estimated at Mw 8.0 was accompanied
by a strong tsunami and shook the area with MMI XI.
Much of the earthquake information that exists in the early
written history of the Americas was preserved by priests accounting
to higher authorities regarding the damages to Churches and
religious-related facilities after the earthquake (hoping for
reimbursement). To give you a flavor of these communications which
are the stuff of much historical work in earthquake damage, following
is a portion of a letter from Don Pedro Porter to the Archbishop
of Lima (in the original Spanish):

"Estado que hoy 8 de Marzo se halla la iglesia Cathedral de al
Concepcion de Chile.

(the earthquake occurred on the 8th of March (Gregorian date) converted to
modern time is the 15th of March Julian date)

1. Toda la iglesia Cathedral esta arrasada por el suelo sin haber mas de una
capilla de Nuestra Senora de las Nieves en que caran hasta
cuarenta personas.

2. Todas las Rtnas, ingresos y diezmos que ha tenido en veinte
y dos meses han montado 141 pesos de suerte que la mayor parte
de vino y ceras para las misas y grasa para las lamparas lo ha
proveido el Obispo del poco caudal que tiene y limosnas que
ha juntado.

- Ornamentos son tan pocos y tamlien lo son los que algunos o
los mas indecentes no sirven y todos, buenos y malos, no valen
200 pesos.

- Plata de senor de la Iglesia tiene hasta valor de 800 pesos.

- Vigas estan guardadas. Los que quedaron sanas del terremoto
hasta 50 y otros tantos tirantes y algunas tablas y tejas que
todo valdra hasta 200 pesos.

- Compnese el Cabildo de undean arcediano, dos canonigos y
dos curas ...

- Todas las canongias estan vacs por renuncias que hicieron de
ellas en mis manos sus propietarios.

-Clerigos sin ocupacion hay, los seis servian los fuertes que se
despoblaron.

-Campanas tiene una que sirve y otras dos se hicieron pedazos
en el terremoto.

Este es el verdadero estado en que se halla la Igesia Cathedral.

U.S./CANADA

The two strongest earthquakes in the U.S./Canada on this date have
both occurred near the California-Nevada border.
In 1860, an event estimated a Mw 7.0 occurred near Carson City,
in western Nevada. This earthquake was felt over a considerable
area of Nevada and portion so of north and Central California.
The MMI intensity in the epicentral area is unknown as the quake
occurred in an unsettled region . It was very violent at Carson
City where merchandise was thrown from shelves. Rock and landslides
were reported from Pyramid Lake and Carson City. The quake was
felt as far as Yreka, CA and to Utah in the east.
The other event of note for today occurred in 1946 (March 15)
in the Walker Pass/Coso Junction region of California. This earthquake
caused moderate damate at Onyx SW of the epicenters. Damage to brick
buildings, chimneys, walls and plaster occurred. Concrete was
broken up. Dishes broke, windows cracked and books and pictures
fell. Cracks formed in the ground and in the Los Angeles Aqueduct
where boulders fell blocking the line near San Canyon.
There were landslides in many of the local canyons. Pipes were
broken as far away a Bakersfield. This Ms 6.4 earthquake was felt
as far away as Calaveras County in th enorth to San Diego in
the South and from San Luis Obispo to Death Valley (an area of
about 65,000 square miles).
The earthquake was preceded by a foreshock, felt by many but
described as slight. It was followed by a strong series of
aftershocks.