QUIET CONDITIONS OUTSIDE NORTH AMERICA, ACTIVE WITHIN

SUMMARY

It was one of those days when everything seemed to be happening
close to home. The only significant earthquakes today occurred
in North America. Other areas of the world saw little activity.

GLOBAL

The largest events of the day occurred in southern Panama/Colombia
(Mb 4.8) and in Guerrero, Mexico (Mb 4.4). Smaller activity was
recorded south of Honshu (Mb 4.2) and in the Swiss Alps (Ml 3.9).
A Mb 4.5 was also listed in the Fiji Islands.

U.S./CANADA

Earthquakes of M>=4 hit off both ends of California today with
a Ml 4.4 off Ferndale in northern California and a Ml 4.1 south
of Yuma in the Baja California region. These were the first events
of Ml>=4 in the region since the Ml 4.4 in the Joshua Tree area
of So. California on April 5, which started the current drought of
earthquakes in that area.
A Ml 2.2 aftershock of the Baja quake was also recorded, however,
the major activity continued to occur in the north and Central
portions of California. A Ml 3.0 occurred near Gilroy, continuing
the trend to larger earthquakes in Central California over the
past 10 days. Other events of Ml>=2 occurred near Lee Vining (Ml 2.1);
Tres Pinos (Ml 2.1), Redding (Ml 2.9), Mammoth Lakes (Ml 2.2);
Parkfield (Ml 2.2) and the aforementioned events off the Coast of
Northern California (Ml 4.4 and 2.2).
A Ml 2.0 was also listed near Duval Washington, however three
events of Ml<2 also occurred near Deming. On Vancouver Island,
a Ml 2.7 was also recorded.
The Central Rocky Mountains also saw a light earthquake today -
a Ml 2.5 near Lyman, WY. The region of Yellowstone and Canyon
Junction WY were quite seismic over the weekend including earthquakes
of Ml 2.0 near Orangeville, UT; 2.2 near Minersville,
2.2, 2.5, and 2.6 E of Canyon Junction, WY and Ml 2.5 near
Lyman, WY. A Ml 2.0 also was recorded today near Jackson Lake WY.
Even the eastern U.S. and southeastern Canada saw some unusual
activity today. In Ohio, a Ml 2.4 event occurred yesterday. Also
over the weekend Canada saw events of 1,5 north of Minnesota;
2.3 and 1.0 in the Charlevoix Seismic Zone, Quebec; and a Ml 3.1
near Maniwaki, Quebec.
Neither Alaska nor Hawaii registered any local earthquakes of
Ml>=3 today.


NEW ZEALAND

A series of events struck north of Lake Taupo this afternoon
in New Zealand. The largest was Ml 3.7 near Murupara, North
Island. This was Felt (IGNS) in the Ureweras area, and was
followed by at least 5 small aftershocks.

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 were no M- or X- class solar flares recorded.

Flare # START MAX END CLASS

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020429events.txt

TIDAL EFFECTS

May 01 is the eighteenth 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
East Africa MB>=4.0 23 3.1 0.01
New Zealand MB>=4.0 19 2.2 0.05
Yellowstone MB>=2.0 19 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

Utah MB>=2.0 -19 -2.0 0.05

TOMORROW IN EARTHQUAKE HISTORY

GLOBAL:

The following events of Mw>=7 have occurred on this date in
recorded history:

MO DA HR MN SC YEAR LATIT LONGIT DEP MW LOCATION

4 30 15 0 0 1839 35.000 136.000 0 7.0 No. Honshu, Japan
4 30 7 17 5 1919 -19.000 -172.500 60 8.4 Tonga Islands
4 30 11 4 0 1921 19.700 -104.300 0 7.8 Michoacan, Mexico
Intense shaking at Jalisco, Colima and parts of Michoacan and
Nayarit.

4 30 2 55 30 1939 -10.500 158.500 25 8.1 Solomon Islands
Twelve people were drowned in the accompanying Tsunami at Solomon
Island, Russel Island and Guadalcanal.

4 30 1 23 32 1949 6.500 125.000 130 7.4 Mindanao, Philippines
Intensity VI at Lagao, IV at Davao City.

4 30 13 2 26 1954 39.300 22.200 15 7.2 No. Greece
Greece had scarcely begun to rebuild from the ruins left
by an earthquake on the Ionian Islands when Thessaly
suffered this new earthquake. Sofiades, Farsala and 32 other villages
on the plain of Thessaly were destroyed; considerable damage
was done at Trikkala, Kardhitsa and Domoko. The shock caused
31 deaths, injured 717, damaged or destroyed 13,356 houses and
did damage of about $5 million. Most of the places affected
lie at the foot of the mountains on the edge of the Trikkala basin.
The quake was felt over 260,000 square km. Strong aftershocks
continued for more than 3 months.

4 30 7 7 22 1986 18.500 -103.700 0 7.3 Michoacan, Mexico
Some damage (V) in Mexico City. Slight damage at
Ciudad Guzman and Guadlajara. Felt strongly in central and
southwestern Mexico.

U.S./CANADA

Following are events of Mb>=5 which have occurred in this region on

MO DA HR MN SC YEAR LATIT LONGIT DEP MW LOCATION

4 30 2 5 0 1899 38.500 -87.000 0 5.0 Indiana area
Southwestern Indiana and eastern Illinois. Strongest at Jeffersonville
and Shelbyville, IND. A few chimneys were thrown down and brick
walls cracked at Vincennes. Felt as far as Kentucky.

4 30 10 55 38 1936 44.000 -128.500 0 5.5 Off Coast of Oregon
4 30 7 45 45 1945 47.400 -121.700 0 5.0 Washington state, U.S.
4 30 8 46 0 1945 47.400 -121.700 0 5.0 Washington state, U.S.
Aftershocks of event on April 29 cuased light damage at North Bend, WA.

4 30 4 49 46 1947 59.000 -139.000 0 6.3 Southeast Alaska
4 30 9 17 0 1957 51.900 -175.200 33 6.0 Andreanoff Islands, Aleutians
4 30 17 26 30 1964 59.800 -142.400 23 5.0 Southeast Alaska
4 30 4 29 10 1975 60.085 -153.239 149 5.3 Central Alaska
4 30 16 35 36 1999 53.846 -164.125 52 5.0 Unimak Islands, Aleutians
4 30 8 29 25 2000 50.830 -130.650 10 5.3 British Colombia
4 30 10 13 3 2000 51.011 -130.381 10 5.5 British Colombia
4 30 5 24 19 2001 58.694 -176.681 399 5.8 Andreanoff Islands, Aleutians

EARTHQUAKE LISTINGS

ASIA

O: 28APR2002 05:09:21 34.9N 80.4E ML=3.4 ASC N of Sumxi (Xizang), KHZ

O: 25APR2002 19:06:42 36.7N 70.7E ML=3.1 ASC W of Khaneqa KHZ
O: 27APR2002 17:04:28 36.9N 70.5E ML=3.3 ASC E of Nowabad KHZ
O: 28APR2002 09:11:13 36.4N 70.3E ML=4.0 ASC of Emend (Badakhshan), KHZ

O: 25APR2002 17:30:13 35.7N 83.2E ML=4.0 ASC of Yeyik (Xinjiang), KHZ

O: 25APR2002 10:54:32 35.5N 72.3E ML=3.2 ASC e of Tal (N.W.F.P.), KHZ

O: 25APR2002 08:26:53 34.9N 76.0E ML=3.6 ASC W of Dodari (Jammu & KHZ

O: 24APR2002 11:47:26 27.7N 76.0E ML=3.6 ASC of Dantil (Rajasthan), IMD

O: 27APR2002 04:49:07 32.3N 137.6E MB=4.4 NEI SOUTHEAST OF HONSHU, JAPA

SOUTH PACIFIC ISLANDS

CARIBBEAN/CENTRAL/SOUTH AMERICA

O: 28APR2002 21:28:49 9.9N 70.6W Mc=3.6 ULA Límite de los Edos. Lara y Zul

O: 29APR2002 03:14:02 16.9N 100.1W ML=3.4 SSN COSTA DE GUERRERO, MEXICO
O: 29APR2002 01:34:48 17.0N 100.1W ML=3.6 SSN COSTA DE GUERRERO, MEXICO

O: 29APR2002 02:06:52 18.6N 104.2W ML=4.4 SSN COSTA COLIMA, MEXICO

O: 28APR2002 21:25:04 13.9N 91.6W ML=4.4 SSN COSTA GUATEMALA, MEXICO

O: 28APR2002 20:17:27 16.7N 99.8W ML=3.4 SSN COSTA DE GUERRERO, MEXICO

O: 29APR2002 02:42:57 6.1N 78.8W MC=4.8 CASC Colombia, Central America

O: 29APR2002 05:15:18 10.3N 84.0W MC=3.6 CASC Costa Rica, Central America

NEW ZEALAND/AUSTRALIA

O: 29APR2002 13:33 38.6S 176.8E ML=3.7 IGNS SE of Murupara, N.Z.

OCEANIA

EUROPE/MIDDLE EAST/AFRICA

O: 29APR2002 15:14:09 46.1N 8.6E Ml=3.9 LDGM SWITZERLAND

U.S/CANADA

CALIFORNIA/NEVADA

O: 29APR2002 00:43:29 40.6N 124.5W ML=4.4 NCSN WNW of Ferndale, CA
O: 29APR2002 00:43:29 40.6N 124.5W ML=4.4 NEI NEAR COAST OF N CALIF.
O: 29APR2002 06:26:52 40.3N 124.4W ML=2.2 NCSN N of Punta Gorda, CA

O: 29APR2002 03:03:09 36.0N 120.5W ML=2.2 SCSN NW of Parkfield, CA

O: 28APR2002 01:23:56 37.0N 115.0W ML=2.9 NEI CALIFORNIA-NEVADA BORDER

O: 29APR2002 11:52:28 40.6N 122.4W MD=2.9 NEI NORTHERN CALIFORNIA
O: 29APR2002 04:52:28 40.6N 122.4W ML=2.9 NCSN NNW of Redding, CA

O: 28APR2002 22:17:33 37.9N 118.6W ML=2.2 NCSN NNE of Toms Place, CA

O: 29APR2002 01:53:45 35.6N 117.5W ML=1.9 SCSN ESE of Ridgecrest, CA

O: 29APR2002 06:09:33 36.6N 121.2W ML=2.1 NCSN NW of Pinnacles, CA

O: 29APR2002 07:16:52 34.2N 116.9W ML=1.9 SCSN NNW of Mt. San Gorgonio, CA

O: 29APR2002 07:34:44 38.0N 118.7W ML=2.1 NCSN SSW of Qualeys Camp, NV

O: 29APR2002 22:36:57 37.0N 121.6W ML=3.0 NCSN SSW of Gilroy, CA

O: 29APR2002 12:24:41 32.1N 115.0W ML=4.1 SCSN SSW of Yuma, AZ
O: 29APR2002 22:27:43 32.1N 115.0W ML=2.1 SCSN SSW of Yuma, AZ

PACIFIC NORTHWEST/CANADA

O: 26APR2002 02:31:39 59.3N 136.6W ML=3.0 PGC ST. ELIAS MOUNTAINS, B.C. - Y.

O: 26APR2002 04:46:50 51.1N 130.9W ML=2.6 PGC SOUTH OF MORESBY ISLAND, B.C.

O: 26APR2002 11:08:07 52.5N 132.2W ML=2.4 PGC WEST COAST MORESBY ISLAND, B.C

O: 29APR2002 08:49:02 48.8N 122.3W ML=1.8 PNSN WSW of Deming, WA
O: 29APR2002 10:15:15 48.8N 122.3W ML=1.6 PNSN WSW of Deming, WA
O: 29APR2002 15:49:02 48.8N 122.3W ML=1.6 PGC S Abbotsford BC

O: 29APR2002 04:29:33 49.3N 128.0W ML=2.7 PGC WSW Gold R. BC

O: 29APR2002 07:05:02 47.8N 121.9W ML=2.0 PNSN ENE of Duvall, WA
P: 2MAY2002 10-05/-1 47.4N 122.2W 2.0-3.2 BAAAA Seattle area, WA

ROCKY MOUNTAIN AREA

O: 26APR2002 10:54:54 44.7N 110.2W ML=2.6 UUSN E of Canyon Junc., WY

O: 26APR2002 18:18:28 39.3N 111.2W ML=2.0 UUSN NW of Orangeville, UT

O: 27APR2002 07:06:40 38.1N 112.8W ML=2.2 UUSN SE of Minersville, UT

O: 27APR2002 20:22:08 44.8N 111.0W ML=2.2 UUSN NNE of W. Yellowstone, MT

O: 29APR2002 14:29:09 41.5N 110.4W ML=2.5 UUSN NNW of Lyman, WY

EASTERN U.S./CANADA

O: 27APR2002 07:09:20 47.0N 76.3W MN=3.1 GSC 70 KM N FROM MANIWAKI, QUE.

O: 28APR2002 00:07:23 41.9N 81.4W MN=2.4 GSC OHIO, U.S.

ALASKA

HAWAII