EARTHQUAKE OF MB>5.2 HITS BAJA CALIFORNIA REGION SOUTH OF YUMA, ARIZONA

SUMMARY

A moderate earthquake of Mb 5.2+ hit the region of Baja California
south of Yuma Arizona this afternoon. This is the first event of
Mb>=5 in the region bounded by 32-30N 116-114W since a Mb 5.3 on
Dec. 3, 1991. It is the third largest event in the region in the
past 35 years - the others being a Mb 5.4 on Aug 31, 1988;
Mb 5.7 on July 17, 1975; and Ms 6.2 on Nov. 23, 1963. SCSN is giving
the following preliminary parameters to this event (which is listed
as much larger at teleseismic observatories, as noted by the
magnitude from NORSAR (NOR)):

O: 08DEC2001 23:36:08 31.9N 115.0W ML=5.2 SCSN SSW of Yuma, AZ
O: 08DEC2001 23:36:07 30.0N 114.4W Mb=5.5 NOR GULF OF CALIFORNIA

The area had been expected in these daily reports to see strong activity
around this time from a number of effects which tend to enhance seismicity
levels. These effects included:

1) Far-Field Triggering from the great Kunlun Mts. earthquake of
Nov. 14, 2001 (Mw 8.1)

The event lies directly on the boundary of the S-wave shadow zone
(107 degrees) from the great Kunlun Mts. earthquake. The far-field
forecast from that event had stated:

"103-107 degrees***: California/Baja border (about 32-34N)

***: The strongest triggering is always expected to be along the
shadow zone boundary between 103-107 degrees from the epicenter."

and

"Areas of U.S. and Canada where triggering may occur (Ml>=4.0)

...Southern California - esp. in the Calexico to Bombay Beach region"

This epicenter is also at 103 degrees from the Ms 6.2 earthquake
on South Island, New Zealand yesterday - at the p-wave shadow zone
boundary. That earthquake was the strongest in that region in more
than 35 years.

DELAYED EFFECTS FROM NEW BRITAIN EVENT MW 7.1 OCT. 31, 2001

On Nov 26, this forecast had reminded us of the relation between
moderate or strong events in Southern California and earlier events
in southern California:

'Seismicity often increases in So. California about a month following
strong earthquakes in the New Britain region. The far-field aftershock
forecast of the Mw 7.0 New Britain event on October 31 had noted:

" There is a strong relationship between New Britain events and
succeeding earthquake in southern California especially in the
area of Anza to the Salton Sea. This is probably because wave
fronts from New Britain arrive approximately parallel to the
San Andreas in this region, promoting larger events. This area
should remain active for several week. A larger event in this
area often occurs 28-33 or 43-46 days after the event in New
Britain, so the danger is not yet over."

The danger period should begin on November 28 and last through
Dec. 3, 2001.'

Today's event between the two stated danger periods, but could well
have been related to the same triggering effects.

GLOBAL

The strongest earthquake in the world today was an Mj 6.0 in the
Ryukyu Islands, south of Japan. This may also have been a FFA from
the Kunlun Mts. earthquake as it occurred near 33-34 degrees from that
event in an area and distance where FFA was expected.
Other global activity was recorded as a Mb 5.0 in the Aegean Sea/
Northern Greece area; a Mb 4.5 aftershock in the Qinghai, China area
as a classical aftershock of the Kunlun Mt. great event.
Other likely FFA from the Kunlun Mts. continued with a Mb 5.2 in
southern Peru at 143 degrees (the core-mantle shadow zone boundary) and
5 events in central and eastern Mexico at 105-107 degrees (the s-wave
shadow zone boundary) from the Honshu mainshock.
The only other event noted in teleseismic catalogs was a Mb 4.8+
event near Svalbard. This event lies at 59 degrees from the Honshu mainshock
in a region and distance where FFA was expected to occur as stated in the
forecast:

"59-61 degrees: ... Svalbard"

The eruption of Kick-'em-Jenny may be over. The status has been reduced
from alert status orange to alert status yellow. For additional details
on the continuing progress of this volcano see:

http://www.uwiseismic.com/

U.S./CANADA

Activity in the U.S/Canada region today was interesting to say the
least. The largest event was the Mb 5.2+ earthquake in the Baja, California
region south of Yuma which is discussed in the summary section above.
This, however was not the most unusual earthquake of the day - that
honor was reserved for a Ml 3.9 which occurred earlier this morning in
the Huntsville, Alabama region. This event also occurred at 107 degrees
from the great Qinghai China earthquake and is probably an FFA from that
event. The FFA forecast had stated:

"Areas of U.S. and Canada where triggering may occur (Ml>=3 or unusual events)

...Virginia"

This is the largest event within 100 km of this epicenter since
a Ml 4.4 occurred on Feb 18, 1964. Other larger areal events have
occurred in 1927 (ML 4.2) and in 1902 (Ml 4.2).
An unusual earthquake, not because of it's location but because
of magnitude occurred as a Ml 3.0 in Yellowstone, N.P today as well,
this is the largest event in this region in nearly a year and appears
to be the culmination of the swarm that started there immediately
after the Honshu mainshock.
California also saw it's share of activity today. Besides the Mb 5.2+
earthquake in Baja California, two other events of Ml>=3 occurred
today. These were in the Salinas, CA area area (at 73 degrees from
the Honshu mainshock, probably an FFA) and as a Ml 3.2 off the coast
of Northern California west of Punta Gorda. The are around Salinas
has been relatively active this year with 8 groups of events containing
a Ml 3.4 or larger mainshock in the past year within 50 km of this
epicenter. The epicenter, however, appears to lie to the west and
south of most of these other swarms and perhaps lies on a different
faultline.
Other events of Ml>=2 in the California/Nevada area were recorded
near Yucca Valley (Ml 2.1); Calexico (Ml 2.1); Obsidian Butte (Ml 2.1)
in southern California and a Ml 2.5 aftershock South of Yuma, AZ.
In northern California such events were recorded as aftershocks
of the Salinas earthquake (Ml 2.1, 2.6) and as a Md 2.1 east
of the Geysers.
A Ml 3.4 was also recorded along the Alaska/Yukon Territory
border. Hawaii was unavailable because of the USGS link shutdown.
No other reports were available from Canada or the eastern or Central
U.S.

NEW ZEALAND

Aftershocks continued from the Haast, South Island earthquake yesterday.
The IGNS Cannon Point seismogram shows only minor activity in
the region beyond those events today.

A News wire story on the Earthquake in southern South Island
yesterday can be found at:

http://abcnews.go.com/wire/World/ap20011207_1887.html

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 at quiet conditions today. There
was one moderate M-class solar flare observed with the following
parameters:

Flare # START MAX END CLASS

150 + 0602 0634 0655 M3.4

An earthquake of Ms 4.8+ occurred in the region north of Svalbard
at 06:44 UT. Svalbard is located at 80N. High latitudes are strongly
affected by solar flare effects.

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20011119events.txt

TROPICAL STORMS

There were tropical storms in any oceans of the world reported
today. Cyclone Kajiki has dissipated to a tropical rainstorm.

TIDAL TRIGGERING (LUNAR)

Statistics have been done on many regions of the world in terms of
relationship of significant regional earthquakes with respect to lunar cycle.
Each report will summarize the most likely areas for tidal triggering
for the next day based on these statistics. It is expected
that tidal triggering will add an additional 0.5 - 1.0 units of
magnitude to events which are about to occur or will move these
events forward in time by up to seven days in the regions where
there is a statistical correlation between lunar phase and
earthquakes.

December 09 is the twenty-fifth 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

Antarctica MB>=4.0 343 2.8 0.02
India MB>=4.0 48 2.0 0.05
Yellowstone MB>=2.0 20 2.1 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

Arctic MB>=4.0 -36 -2.3 0.05

EARTHQUAKE LISTINGS

GLOBAL

NEW ZEALAND/AUSTRALIA

O: 7Dec2001 22:47 43.8S 168.0E ML=4.2 IGNS West of Haast, N.Z.
O: 8Dec2001 01:10 43.9S 168.4E ML=4.4 IGNS West of Haast, N.Z.
O: 8Dec2001 01:54 44.1S 168.7E ML=4.1 IGNS West of Haast, N.Z.
O: 8Dec2001 02:26 44.0S 168.3E ML=4.1 IGNS West of Haast, N.Z.
Note: (IGNS) Aftershocks of 8.27 a.m. event

ASIA

O: 07DEC2001 10:05:56 02.7S 100.9E MS=3.5 ASC SSW of Mukomuko, Sumatera

O: 08DEC2001 04:12:49 35.5N 92.8E Ms=4.5 GSSC QINGHAI, CHINA

O: 08DEC2001 20:29:31 28.0N 129.7E Ms=5.8 GSSC RYUKYU ISLANDS, JAPAN
O: 08DEC2001 20:29 28.3N 129.3E Mj=6.1 NIED NEAR_AMAMI-OSHIMA_ISLAND, JAPAN

O: 08DEC2001 09:02:08 13.2N 122.8E ML=4.1 NOR Luzon, Philippine Islands

CENTRAL/SOUTH AMERICA

O: 08DEC2001 04:17:16 16.4S 72.7W MB=5.2 IGP Felt III Camana, Peru
Note: This event occurred at 143 degrees from the Kunlun Mts. in
and area and at a distance where strong FFA triggering (the core-mantle
shadow zone boundary) is expected.

O: 08DEC2001 04:58:25 17.2N 94.2W ML=4.3 SSN ISTMO DE TEHUANTEPEC, MEXICO

O: 08DEC2001 01:03:18 18.4N 103.5W ML=4.1 SSN COSTA DE MICHOACAN, MEXICO

O: 07DEC2001 21:43:58 13.8N 93.4W ML=4.2 SSN COSTA MEXICO-GUATEMALA, MEXICO

O: 08DEC2001 01:43:52 17.1N 100.0W ML=3.7 SSN GUERRERO, MEXICO
O: 07DEC2001 19:00:15 17.0N 100.1W ML=3.8 SSN COSTA DE GUERRERO, MEXICO
O: 07DEC2001 17:45:33 16.8N 99.7W ML=3.5 SSN COSTA DE GUERRERO, MEXICO
O: 07DEC2001 17:42:11 16.9N 99.7W ML=3.7 SSN COSTA DE GUERRERO, MEXICO
O: 07DEC2001 17:13:23 16.9N 99.8W ML=3.7 SSN COSTA DE GUERRERO, MEXICO

EUROPE/AFRICA/MIDDLE EAST

O: 8DEC2001 19:12:32 40.8N 31.2E ML=3.2 KAN DUZCE,TURKEY

O: 07Dec2001 19:44:50 39.1N 23.4E MS=4.5 GSR AEGEAN SEA
O: 07DEC2001 19:44:53 39.4N 23.8E ML=5.0 NOA GREECE
O: 07DEC2001 19:54:53 39.3N 23.5E ML=3.0 NOA GREECE
O: 07DEC2001 19:55:48 39.3N 23.7E ML=3.0 NOA GREECE
O: 07DEC2001 20:27:59 39.3N 23.7E ML=3.3 NOA GREECE
O: 07DEC2001 20:28:57 39.2N 23.7E ML=3.9 NOA GREECE
O: 07DEC2001 21:43:11 39.3N 22.7E ML=3.2 NOA GREECE
O: 07DEC2001 22:10: 2 35.8N 23.5E ML=3.0 NOA GREECE
O: 07DEC2001 22:40:60 39.2N 23.5E ML=3.5 NOA GREECE
O: 08DEC2001 00:39:14 39.2N 22.7E ML=3.2 NOA GREECE
O: 08DEC2001 03:31:54 39.3N 23.5E ML=3.0 NOA GREECE
O: 08DEC2001 04:31:35 39.3N 23.8E ML=3.6 NOA GREECE

O: 08DEC2001 00:48:17 41.5N 20.6E ML=3.2 NOA GREECE

OCEANIA

O: 08DEC2001 06:44:24 80.8N 0.2W Ms=4.8 GSSC NORTH OF SVALBARD
Note: This event lies at 59 degrees from the Honshu mainshock in a region
and distance where FFA was expected to occur as stated in the forecast:

"59-61 degrees: ... Svalbard"

U.S/CANADA

CALIFORNIA/NEVADA

O: 08DEC2001 23:36:07 30.0N 114.4W Mb=5.5 NOR GULF OF CALIFORNIA, M

O: 08DEC2001 01:15:15 33.2N 115.6W ML=2.1 SCSN NNE of Obsidian Butte, CA
O: 08DEC2001 02:24:56 32.4N 115.4W ML=2.1 SCSN S of Calexico, CA
O: 08DEC2001 23:36:08 31.9N 115.0W ML=5.2 SCSN SSW of Yuma, AZ

O: 08DEC2001 21:05:24 34.2N 118.8W ML=1.9 SCSN NNE of Thousand Oaks, CA

O: 08DEC2001 13:48:59 36.7N 121.6W ML=3.4 NCSN ENE of Salinas, CA
O: 08DEC2001 13:48:58 36.8N 121.3W Md=2.9 NCSN W of Tres Pinos, CA
O: 08DEC2001 13:57:48 36.7N 121.3W Md=2.1 NCSN W of Tres Pinos, CA
O: 08DEC2001 15:28:07 36.8N 121.3W Md=2.6 NCSN W of Tres Pinos, CA

O: 08DEC2001 11:43:05 40.3N 124.2W Ml=2.7 NCSN NE of Petrolia, CA
O: 08DEC2001 11:42:59 40.3N 124.9W ML=3.2 NCSN W of Punta Gorda, CA

O: 08DEC2001 8:04:00 34.4N 116.5W ML=2.1 SCSN N of Yucca Valley, CA

O: 08DEC2001 16:22:43 38.7N 122.7W Md=2.1 NCSN ESE of The Geysers

ROCKY MOUNTAIN AREA

O: 08DEC2001 19:08:03 44.8N 111.0W ML=3.0 UUSN NNE of W. Yellowstone, MT
Note: This is the first event of Ml>=3 in the Yellowstone region since
a Ml 4.3 and 3.6 on November 24, 2000, more than a year ago. It appears
to be the culmination of the swarm of earthquakes that began in the
area immediately following the Honshu Mw 6.5 on Dec. 2, 2001.

O: 08DEC2001 22:55:05 45.4N 110.7W MD=0.0 MBMG MONTANA
O: 08DEC2001 22:22:31 44.8N 111.0W MD=0.0 MBMG MONTANA
O: 08DEC2001 19:17:54 44.8N 111.0W MD=0.0 MBMG MONTANA
O: 08DEC2001 19:14:05 44.7N 111.0W MD=0.0 MBMG MONTANA
O: 08DEC2001 19:08:03 44.8N 111.0W MD=2.3 MBMG MONTANA
O: 08DEC2001 17:01:33 44.7N 111.0W MD=0.0 MBMG MONTANA
O: 08DEC2001 16:20:00 44.8N 111.0W MD=0.2 MBMG MONTANA
O: 08DEC2001 16:09:23 44.8N 111.4W MD=1.4 MBMG MONTANA
Note: These are aftershocks and foreshocks of the Ml 3.0 in Yellowstone
this afternoon.

O: 08DEC2001 11:00:39 45.6N 112.0W MD=0.0 MBMG MONTANA
O: 07DEC2001 23:44:30 46.3N 112.1W MD=1.0 MBMG MONTANA

EASTERN U.S./CANADA

A highly unusual earthquake occurred this morning in Alabama U.S.
with the following NEIS epicentral parameters:

O: 8DEC2001 1:08:21 34.7N 86.3W ML=3.9 CERI ENE of Gurley, ALA
O: 08DEC2001 01:08:21 34.7N 86.3W ML=3.9 NEIS Alabama
O: 08DEC2001 01:08:22 34.7N 86.2W ML=3.8 JIEE WNW of Scottsboro, AL
Note: This event occurred at 107 degrees from the great Qinghai
China earthquake and is probably an FFA from that event. The FFA forecast had
stated:

"Areas of U.S. and Canada where triggering may occur (Ml>=3 or unusual events)

...Virginia"

This is the largest event within 100 km of this epicenter since
a Ml 4.4 occurred on Feb 18, 1964. Other larger areal events have
occurred in 1927 (ML 4.2) and in 1902 (Ml 4.2).

ALASKA

O: 08DEC2001 14:36:22 59.3N 136.7W ML=3.4 PGC 4 km WNW Haines AK

P.S. This is the last daily report which will be posted by me until
sometime late in January, 2002. I will be unable to continue this
while on vacation in the eastern U.S.
I have to admit some pangs of guilt in leaving at this time, while
global earthquake data is difficult to come by because of the problems
at the USGS, however. It seems that now, more than ever, this type
of summary is needed in an accessible web site. Perhaps, however,
absence makes the heart grow fonder, and we will all appreciate
a bit more the usefulness of this type of report when it recontinues
next year.
Thank you all for your kindness and seasons greetings. My best
to all.

Lowell