OCEAN RIDGE SYSTEMS CONTINUE ACTIVE AFTER GEOMAGNETIC STORMS

SUMMARY

Seismic activity on mid-ocean ridge systems has been high since the
geomagnetic storms of 21-23 October. This is commonly the case
for about 5-6 days following strong geomagnetic storms. Earthquakes
today (24-25 October) on mid-ocean ridges have included: Central East
Pacific Rise (Mb 4.9) - this event followed this morning's CME by about
12 minutes and was nearly anti-solar to the CME; the Greenland Sea
(Mb 4.1); and the South Mid-Atlantic Ridge (Mb 4.4). Occurring on 22-23
October were events in the southernly South Mid-Atlantic Ridge (Mb 5.0);
the West Chile Rise (Mb 4.8); the northerly South Mid-Atlantic Ridge
(Mb 4.3). Typically the inter-event time between ocean ridge events
is about 2.5 days, so having six in the course of 3 days is a rate
increase of about five times over background. This is typical of
rate increases on ocean ridges following strong geomagnetic storms.

GLOBAL

Seismicity in the rest of the world over the past three days has
be relatively quiet outside the ocean ridges. Besides the Mb 4.9
on the East Pacific Rise which was the largest event recorded
today and which occurred 12 minutes after the CME, only one other
event of MB>=4.5 has been reported in the past day-and-a-half -
a Mb 4.7 in the Northern Molucca Sea. An earthquake of Mb 4.7 was
listed yesterday in Nicaragua. The Nicaraguan local network (SIS)
is also listing a Mb 4.0 at 09:09 UT this morning, but this is
probably a misread teleseismic arrival from the East Pacific Rise.
Only one earthquake of Mb>=5 has been reported during the
duration of the current proton storm ( a Mb 5.2 in the Virgin
Islands early on Oct 24 was the last Mb>5.
A series of small events has been occurring in the Canary Islands
off the west coast of Africa near Tenerife in the Ml 2-3 range. These
events may precede a volcanic episode. For details of these events see:
http://www.geo.ign.es/servidor/sismo/cnis/proximo/proximo.html

U.S./CANADA

An Ml 3.1 earthquake was recorded in southern California in the
region south of Los Angeles this morning near San Clemente Island.
A Ml 1.7 was seen later in the day about 100 km easst of this event.
Several quakes of Ml 2.9 also occurred in Bishop; Goldstone
Lake (near Barstow); and at Mammoth Lakes. Other events of Mv>=2
occurred in the region at the Geysers (Ml 2.3, 2.0).
The strongest event reported in the northwest U.S. was a Ml 2.3
which occurred today was a Ml 2.2 near Salem, Oregon. The largest
event of the day was a Ml>3 off the coast of Oregon (PNSN, poor
parameters at this time).
A Ml 3.1 and 3.6 occurred in Central Alaska and the activity
in Hawaii contined at high rates with a Ml 3.6 and Ml 3.1 today
near Mauna Loa volcano.
As reported yesterday, the Ml 3.3 in the region north of Bangor
Maine is the largest in the New England area in more than a year.
No other activity was reported in the U.S./Canada region today with
Ml>=2.

NEW ZEALAND

An earthquake of Ml 3.7 occurred on South Island N.Z. this
morning near Kaikoura. This epicenter is about 100 km south
of the region near Seddon which has been active over the
past three days. The on-line seismometer showed a series of
light regional shocks today.

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

GEOMAGNETIC/SOLAR FIELDS

A sudden change in geomagnetic field occurred with a minor CME
hit this morning at 08:52 UT. The event was well recorded by
two seismometers show associated changes at the time of the CME arrival
These are IU/KBS - Spitzbergen, Norway, which has initial motion UP,
and So. Karori, NZ. (IU/SNZO) which has initial motion DOWN.
The CME arrival is well timed by the loss of seismogram signal at the
Bozeman, Montana station.
This loss continues from about 3 minutes. See:
http://mbmgquake.mtech.edu/earthworm/wavef_disp/BOZ_BHZ_US.2001102500.gif
http://mbmgquake.mtech.edu/earthworm/wavef_disp/BOZ_SPZ_US.2001102500.gif
http://mbmgquake.mtech.edu/earthworm/wavef_disp/BOZ_LPZ_US.2001102500.gif

This CME was followed within minutes by a moderate earthquake
at 09:04 UT on the northern East Pacific Rise and a Ml 2.8 in France
at 09:09 UT. An earthquake of Ml 2.3 was recorded in Wyoming about
two hours later.

One X1.1 class flare was also observed on the sun today with
the following parameters:

Flare # START MAX END CLASS

6660 + 1442 1502 1528 X1.3

The CME from this event may arrive in about 2-3 days.

The geomagnetic field remained at quiet conditions today.

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20011025events.txt

TROPICAL STORMS

Tropical Depression Narda has dissipated and is no longer at
threat to Hawaii. No other tropical storms are in progress in
the Atlantic or eastern Pacific at this time.

Super Typhoon Podul now has winds up to 140 knots. It is still
located in the west Central Pacific Ocean (about 20N 154E). Wave
height associated with Podul is about 36 feet.
For a public advisory see:

http://www.wunderground.com/auto/HurricaneSite/tropical/wp200101.public.html

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.

October 26 is ten days after the beginning 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

Alaska MB>=3.0 6 2.0 0.05
Greece MB>=4.0 8 2.0 0.05
Hawaii MB>=2.0 19 2.7 0.02
Kuriles MB>=4.0 22 1.9 0.05
Mammoth Lakes MB>=3.0 19 2.2 0.05
East Pacific Rise MB>=4.0 38 2.3 0.05
Hindu Kush MB>=4.0 20 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

No Regions

EARTHQUAKE LISTINGS

GLOBAL

NEW ZEALAND

O: 25Oct2001 17:52 42.5S 173.8E ML=3.6 IGNS SE of Kaikoura, N.Z.
Note: (IGNS) Felt in Kaikoura

SOUTH PACIFIC ISLANDS

O: 24Oct2001 09:51:13 4.3S 153.8E MB=4.3 NEIS NEW IRELAND REGION, P.N.G.

O: 24Oct2001 18:59:07 16.4S 177.1W MB=4.1 NEIS FIJI ISLANDS REGION

O: 22Oct2001 23:25:22 6.6S 155.0E MB=4.5 NEIS SOLOMON ISLANDS

O: 24Oct2001 14:59:48 23.9S 179.8W MB=4.3 NEIS SOUTH OF FIJI ISLANDS

ASIA

O: 24Oct2001 18:12:57 29.2N 139.3E MB=3.9 NEIS SOUTHEAST OF HONSHU, JAPAN

O: 24Oct2001 13:55:03 46.7N 153.5E MB=4.2 NEIS KURIL ISLANDS

O: 25Oct2001 06:02:46 1.1N 126.8E MB=4.7 NEIS NORTHERN MOLUCCA SEA

O: 22OCT2001 07:10 34.5N 141.9E Mj=3.6 NIED FAR_SE_OFF_BOSO_PEN, JAPAN

O: 21OCT2001 18:37 29.8N 129.7E Mj=4.0 NIED NEAR_TOKARA_ISLANDS, JAPAN

O: 21OCT2001 18:20 35.9N 138.1E Mj=3.6 NIED AKAISHI_MOUNTAINS_REG, JAPAN

CENTRAL/SOUTH AMERICA

O: 25OCT2001 05:51 16.9S 72.8W ML=4.0 IGP Camana, Peru

O: 25OCT2001 09:09:16 12.7N 88.9W MC=4.0 SIS GUATEMALA, C.A.

O: 24Oct2001 12:29:58 10.7N 62.6W MB=4.1 NEIS NEAR COAST OF VENEZUELA

EUROPE

O: 23OCT2001 07:10:03 46.0N 7.8E ML=2.6 STR ITALIE (EST D'AOSTE)

O: 24OCT2001 16:04:23 48.2N 7.2E ML=1.9 STR WNW COLMAR(68)

AUSTRALIA

O: 19OCT2001 17:43 33.6S 120.6E ML=5.2 AGSO Felt in SW Western Australia
Note: This was the largest earthquake in recent history in this
area of Australia. No damage was reported. It was followed by a
series of aftershocks in the Ml>=4 range. For further details see:
http://www.agso.gov.au/bin/listQuakes

This event followed shortly after the Banda Sea earthquake (Mw 7.4)
on October 19 and may have been triggered by it. It lies at 30 degrees
from Banda, not in the expected maximum triggering band, however.

O: 19OCT2001 04:18 23.6S 129.6E ML=4.0 AGSO W. of Alice Springs, Australia
Note: Thanks to E.D.G. for bringing these Australian events to our attention.
This event occurred 50 minutes after the Banda Sea earthquake and is
likely a far-field aftershock from that event as it lies at a distance
of 19-20 degrees distance, a distance where far-field triggering is
expected. For further details see:
http://www.agso.gov.au/bin/listQuakes

OCEANIA

O: 24Oct2001 23:49:35 73.7N 8.9E MB=4.1 NEIS GREENLAND SEA

O: 24Oct2001 21:09:25 22.4S 10.7W MB=4.4 NEIS S MID-ATLANTIC RIDGE
O: 23Oct2001 03:44:29 19.9S 11.7W MB=4.3 NEIS S MID-ATLANTIC RIDGE

O: 25OCT2001 07:57:21 8.9N 104.2W MB=6.3 SIS EAST PACIFIC RISE

O: 25Oct2001 09:04:42 2.7S 102.6W MB=4.9 NEIS CENTRAL EAST PACIFIC RISE

U.S/CANADA

CALIFORNIA/NEVADA

O: 25OCT2001 7:00:52 38.8N 122.8W ML=2.0 NCSN ENE of The Geysers, CA
O: 25OCT2001 6:58:00 38.8N 122.8W ML=1.3 NCSN ENE of The Geysers, CA

O: 25OCT2001 6:41:44 33.3N 118.7W ML=3.1 SCSN NNW of San Clemente Is., CA

O: 25OCT2001 6:39:59 37.5N 118.4W ML=1.7 NCSN N of Bishop, CA
O: 25OCT2001 6:27:17 37.5N 118.4W ML=1.7 NCSN N of Bishop, CA

O: 25OCT2001 5:11:42 34.2N 118.1W ML=1.6 SCSN N of Altadena, CA

O: 25OCT2001 14:31:50 38.1N 122.2W ML=1.4 NCSN SSE of Vallejo, CA

O: 25OCT2001 14:02:45 33.3N 116.3W ML=2.1 SCSN NNE of Borrego Springs, CA

O: 25OCT2001 12:48:56 38.8N 122.8W ML=1.7 NCSN NW of The Geysers, CA
O: 25OCT2001 12:47:40 38.8N 122.8W ML=2.3 NCSN NE of The Geysers, CA

O: 25OCT2001 19:01:54 32.7N 117.2W ML=1.7 SCSN W of San Diego, CA

O: 25OCT2001 18:35:42 35.0N 118.3W ML=1.4 SCSN W of Mojave, CA

O: 25OCT2001 17:29:24 35.2N 117.1W ML=2.9 SCSN SW of Goldstone Lake, CA

O: 25OCT2001 16:56:05 40.5N 124.2W ML=1.8 NCSN SE of Ferndale, CA

O: 25OCT2001 20:10:59 35.0N 117.7W ML=1.8 SCSN NW of Boron, CA

O: 25OCT2001 01:51:52 32.3N 115.2W MC=2.1 SCSN SE of Calexico, CA

PACIFIC NORTHWEST/CANADA

O: 25OCT2001 11:59:48 45.1N 123.4W ML=2.5 PNSN WNW of Salem, OR

O: 25OCT2001 3:18:54 43.1N 127.3W ML>3.0 PNSN Off the Coast of Oregon

ROCKY MOUNTAIN AREA

O: 24OCT2001 22:09:05 48.0N 114.8W MD=1.9 MBMG NW MONTANA

O: 24OCT2001 20:18:18 47.5N 115.5W ML=2.1 MBMG NW MONTANA

O: 24OCT2001 00:08:39 47.6N 113.7W MD=0.0 MBMG NW MONTANA

ALASKA

O: 25Oct2001 13:01:36 62.2N 151.0W ML>3.0 NEIS CENTRAL ALASKA
O: 25OCT2001 13:01:36 62.2N 151.0W ML=3.0 AEIC WSW of Talkeetna, Alaska

HAWAII

O: 25OCT2001 8:24:19 19.8N 155.9W ML=3.5 HVO N of Hualalai Summit, Hawaii
O: 24OCT2001 8:38:22 19.4N 155.5W ML=3.3 HVO SE of Mauna Loa Summit, Hawai