STRONG AFTERSHOCK HITS HINDU KUSH (MS 5.8)

SUMMARY

A strong aftershock hit the region of Hindu Kush this morning. The
parameters of this event follow:

O: 12APR2002 04:00:27 36.2N 69.2E MS=5.8 GSR HINDU KUSH REGION, AFGHAN
O: 12APR2002 04:00:26 35.9N 69.3E MS=5.8 NEI HINDU KUSH REGION, AFGHAN

Hindu Kush was at a triple intersection of FFA effects at this time.
This epicenter is located at 106 deg (at the CM shadow zone boundary) from
the event south of Australia two days ago; at 146 degrees ( at the inner-
outer core shadow zone boundary) from the event in Central Chile
and is 46 degrees from the Taiwan earthquake. The FFA forecasts for
all these events had noted the likelihood of a strong aftershock in
the Hindu Kush region as follows:

From Taiwan:

"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 Taiwan mainshock within 2-3 weeks).

...Hindu Kush/Pakistan (3)"

and

"43-45 degrees: ... Hindu Kush, "

From Chile:

"142-146 degrees: Afghanistan, Hindu Kush,......."

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 North-central Chile mainshock within 2-3 weeks).

...Hindu Kush aftershocks"

and from the Indian-Antarctic Ridge event:

"103-106 degrees***: ... Hindu Kush"

GLOBAL

Other areas experiencing earthquakes today were also at points of
intersection of FFA rings. Among these were earthquakes near the
Indian-Atlantic Triple Junction (Mb 4.9). This event was 60 degrees
from the mainshock south of Australia two days ago and at the CM
shadow zone boundary from northern and Central Chile mainshocks.
Other interesting events at a shadow zone boundaries occurred
in northern Venezuela (Inner-outer core (IOC) boundary from Taiwan and
Ryukyu Is) - Mb 4.5 and the Hindu Kush aftershocks and subsequent
shocks (CM boundary from south of Australia and IOC boundary from
Central Chile. An event of Mb 4.5 also occurred near the antipode
of the northern Chile mainshock in Yunnan, China today.
Local networks showed earthquake so Mb 4.2 in Southern Chile;
Mb 4.0 in western Mexico (Colima/Michoacan); Taiwan (Ml 4.2);
and the Aegean Sea (Ml 4.0) occurring today.

U.S./CANADA

The largest listed earthquake for the U.S./Canada region today
occurred in Hawaii (Ml 3.3). No events of Ml>=3 were located in
other area of the region today.
In California/Nevada 10 tremors of Ml>=2 occurred since the
last daily summary. Eight of these occurred in northern and Central
California including two of Ml 2.8 - at Mammoth Lakes and Northeast
of Madera in Central California. Other events in this area included
a second shock at Mammoth Lakes (Md 2.0); two in the Napa region
(Ml 2.2 and 2.2) and another pair in the Tres Pinos, CA area (Ml 2.0 and
2.1). In southern California the largest event of the day occurred
near Fillmore (Ml 2.7). Earthquakes were also listed near Idyllwild
(Ml 2.1) and Calexico.
In the Pacific northwest a Ml 2.7 was located in the Olympia, WA
area, the largest in that region since an Ml 3.0 near Mt. Vernon
on Feb. 12, 2002.
No earthquakes of Ml>=2 were listed for Canada, the Rocky mountain
states or the eastern U.S. today, however, a Ml 1.8 did occur in
Central Oklahoma this evening.

NEW ZEALAND

IGNS did not locate any new earthquake today. The on-line
seismometer was generally quiet today.

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

GEOMAGNETIC/SOLAR FIELDS

While the geomagnetic field was at quiet conditions today, two
M-class solar flares were observed with the following parameters:

Flare # START MAX END CLASS

9820 1305 1310 1314 M1.4
9890 1731 1802 1817 M4.0

An earthquake of Mb 4.9 occurred in the soutwest Indian Ridge
near the maximum intensity of flare 9890. The area would have
been within 30 degrees longitude of local midnight at the time
of the flare/earthquake, so triggering is possible.

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020412events.txt

TIDAL EFFECTS

April 14 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

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 13 0 0 0 1677 38.700 144.000 0 8.1 So. of Honshu
Strong earthquake on Sanriki, Tsugaru, and Nambo, Japan.
The earthquake was accompanied by a tsunami which attacked Otsuchi,
Miyako and Kuwagasa with height of about 5-6 meters at Miyako Bay.
Houses were washed away and people and animals drowned. 3 big
waves were observed. Hachinohe was damaged by the earthquake.

4 13 19 17 0 1906 23.600 120.400 10 7.1 Taiwan
A moderate earthquake in Kagi and Ensuiko, Taiwan killed 14-15 persons
and resulted in moderate regional damage. This is known as the Tinian
earthquake. 84 were wounded 1794 houses destroyed, 2116 partially
destroyed and 7921 damaged. Fissures and surface faulting were
observed.

4 13 17 57 18 1907 36.500 70.500 260 7.0 Hindu Kush/Pakistan
4 13 15 30 57 1923 55.400 162.800 20 7.3 E. of Kamchatka
4 13 2 42 48 1938 39.367 15.167 291 7.0 Mediterranean/Sicily
4 13 19 55 43 1949 47.100 -122.750 54 7.1 Washington state, U.S.
This earthquake was felt at a MMI VIII for the large area of about
90 miles about the epicenter which was located between Tacoma and
Olympia, Washington. Eight deaths were the result of the earthquake. There
was damage of more than $23 million and many injuries occurred.
Churches, schools and libraries were condemned. The eight capitol
buildings at Olympia were damaged at a cost of repair of about
$2 million. Elsewhere there was heavy property damage caused by
falling walls, chimneys and parapets.
Public utilities were interrupted when gas mains broke and water
pipes were cracked or broken. Telegraph services were also interrupted.
Railroad services were suspenede for several days as railroad
bridges south of Tacoma were thrown out of line.
A large portion of a sandy spit in Puget Sound disappeared. Near
Tacoma a huge landslide involving a half-section of a 360 foot
cliff toppled into Puget Sound.

4 13 16 34 39 1961 39.250 77.750 0 7.6 Northern India
Little information on the effects of this event are available.

4 13 18 4 32 1980 -23.466 -177.297 79 7.2 Tonga Islands

U.S./CANADA

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

4 13 13 0 0 1668 47.100 -70.500 0 5.0 Quebec, Canada
4 13 19 55 43 1949 47.300 -122.500 60 7.0 Washington state, U.S.
See description of this event above.

4 13 3 44 0 1957 48.400 -128.500 33 5.8 Vancouver Island area
4 13 9 7 24 1958 65.820 -155.650 0 6.8 Northern Alaska
4 13 15 38 52 1963 38.217 -119.433 0 5.1 California/Nevada area
4 13 12 25 38 1964 59.570 -143.100 24 5.0 Southeast Alaska
4 13 14 4 59 1964 57.510 -151.300 21 5.4 Southern Alaska
4 13 16 14 6 1964 56.570 -152.140 33 5.1 Southern Alaska
4 13 21 25 33 1964 57.500 -153.900 16 5.5 Southern Alaska
4 13 21 43 16 1964 59.400 -143.100 22 5.1 Southeast Alaska
4 13 23 22 57 1965 54.200 -163.400 36 5.0 Unimak Islands, Aleutians
4 13 21 17 32 1970 61.800 -163.400 0 5.0 Central Alaska
4 13 19 32 50 1975 63.391 -149.773 109 5.0 Central Alaska
4 13 18 20 43 1977 51.699 -179.613 46 5.1 Andreanoff Islands, Aleutians
4 13 2 8 30 1980 54.847 -160.305 38 5.4 Unimak Islands, Aleutians
4 13 16 46 1 1985 54.600 -163.700 0 5.3 Unimak Islands, Aleutians
4 13 0 2 48 1988 57.238 -143.250 10 5.6 Southeast Alaska
4 13 17 16 1 1992 51.650 -173.620 62 5.1 Andreanoff Islands, Aleutians
4 13 20 4 16 1999 53.716 -163.159 33 5.1 Unimak Islands, Aleutians

EARTHQUAKE LOCATIONS

ASIA

O: 12APR2002 19:39:33 35.8N 69.2E MB=4.5 NEI HINDU KUSH REGION, AFGHANISTAN
O: 12APR2002 04:00:27 36.2N 69.2E MS=5.8 GSR HINDU KUSH REGION, AFGHAN
O: 12APR2002 04:00:26 35.9N 69.3E MS=5.8 NEI HINDU KUSH REGION, AFGHAN
O: 12APR2002 04:15:36 35.8N 69.4E MB=4.7 NEI HINDU KUSH REGION, AFGHANISTAN
O: 12APR2002 04:14:44 35.9N 69.2E MB=4.4 NEI HINDU KUSH REGION, AFGHANISTAN
O: 12APR2002 04:00:26 35.9N 69.3E MB=5.8 NEI HINDU KUSH REGION, AFGHANISTAN
O: 12APR2002 16:26:00 35.7N 69.3E MB=4.9 NEI HINDU KUSH REGION, AFGHANISTAN
O: 12APR2002 06:04:06 36.1N 69.2E MB=4.1 NEI HINDU KUSH REGION, AFGHANISTAN
O: 12APR2002 05:51:09 36.0N 69.2E MB=4.2 NEI HINDU KUSH REGION, AFGHANISTAN

O: 10APR2002 23:24:07 3.2N 126.2E MB=3.9 NEI TALAUD ISLANDS, INDONESIA

O: 12APR2002 04:00:26 35.9N 69.3E ML=5.8 ASC W of Zardaspan (Baghlan), NEI

O: 11APR2002 20:19:41 39.5N 74.0E MB=4.6 NEI SOUTHERN XINJIANG, CHINA

O: 11APR2002 20:19:34 39.7N 73.9E ML=5.2 ASC Irkeshtam, Tajikistan KYZ

O: 11APR2002 18:48:30 37.9N 71.7E ML=4.2 ASC NW of Rid-Devlekh, KYZ
O: 11APR2002 09:04:46 38.0N 71.9E ML=3.2 ASC NW of Dana, Tajikistan KHZ
O: 11APR2002 16:06:41 37.0N 71.5E ML=3.4 ASC E of Avdzh, Tajikistan KHZ

O: 12APR2002 05:04:52 22.5N 102.8E MB=4.5 NEI YUNNAN, CHINA

O: 12APR2002 14:41:25 24.6N 121.9E ML=3.4 TAI Ilan, Taiwan
O: 12APR2002 21:02:23 24.5N 121.8E ML=4.4 TAI Ilan, Taiwan

O: 11APR2002 16:27:31 7.8S 117.8E MB=4.4 NEI BALI SEA

O: 12APR2002 20:17:40 9.3S 115.6E MR=4.7 AEIC1 S NUSAPENIDA

O: 11APR2002 17:03:30 8.2S 118.5E MR=5.1 AEIC1 N DOMPU

O: 11APR2002 16:27:30 7.7S 117.5E MR=5.6 AEIC1 N SUMBAWABESAR

O: 11APR2002 08:10:30 8.6S 117.1E MR=4.8 AEIC1 W SUMBAWABESAR

O: 11APR2002 05:12:10 2.4S 121.1E MR=4.9 AEIC1 Molucca Sea

SOUTH PACIFIC ISLANDS

O: 11APR2002 08:03:48 6.2S 151.0E MB=4.6 NEI NEW BRITAIN REGION, P.N.G

O: 11APR2002 20:02:56 17.9S 167.7E MB=4.8 NEI VANUATU ISLANDS

CARIBBEAN/CENTRAL/SOUTH AMERICA

O: 11APR2002 21:34:06 13.8N 90.6W MB=4.3 NEI NEAR COAST OF GUATEMALA

O: 12APR2002 02:43:32 39.2S 73.0W ML=4.2 DGF Temuco, Chile

O: 12APR2002 02:52:22 18.8N 104.2W ML=4.0 SSN COSTA COLIMA, MEXICO

O: 11APR2002 11:48:31 19.1N 104.0W ML=4.0 SSN JALISCO-COLIMA, MEXICO

O: 12APR2002 01:43:48 9.6N 69.7W MB=4.5 NEI VENEZUELA
Note: This event lies 144 degrees from both the Ryukyu and Taiwan events.
The FFA forecast from those earthquake had noted this area as a possible
target of Far-field triggering:

"Other possible events of Mw>=4.5 in the next 10 days appear to be:

Northern Venezuela/Colombia"

and

"142-146 degrees: Colombia, Northern Venezuela"

NEW ZEALAND

OCEANIA

O: 11APR2002 04:47:44 59.5S 26.5W MB=4.5 NEI SOUTH SANDWICH ISL REGION

O: 12APR2002 18:09:45 30.8S 59.5E MB=4.9 NEI SOUTHWEST INDIAN RIDGE
Note: This event lies at a triple ring juncture being 104 deg. from Central
Chile, 107 from Northern Chile and 60 degrees from the mainshock south of
Australia. Note also it is approximately antipodal to southern California.

The area had been expected to see FFA in the forecast after the
South Australian event:

"59-61 degrees: ..... Atlantic-Indian Ridge "

EUROPE/MIDDLE EAST/AFRICA

O: 12APR2002 17:55:58 40.2N 25.3E ML=4.0 KAN AEGEAN SEA

O: 11APR2002 03:41:17 40.3N 42.5E ML=3.3 KAN KARS, TURKEY

U.S/CANADA

CALIFORNIA/NEVADA

O: 12APR2002 12:21:33 41.7N 123.9W ML>2.5 PNSN Northern California

O: 12APR2002 03:02:57 33.7N 116.8W ML=2.1 SCSN SSW of Idyllwild, CA

O: 12APR2002 03:39:41 37.2N 119.9W ML=2.8 NCSN WSW of Coarsegold, CA

O: 12APR2002 05:17:32 37.5N 118.8W ML=2.8 NCSN WSW of Toms Place, CA
O: 12APR2002 07:13:41 37.5N 118.8W ML=2.0 NCSN WSW of Toms Place, CA

O: 12APR2002 13:22:50 38.6N 122.3W ML=2.2 NCSN E of Angwin, CA
O: 12APR2002 14:36:48 38.6N 122.3W ML=2.2 NCSN E of Angwin, CA

O: 12APR2002 17:20:29 34.5N 118.8W ML=2.7 SCSN NE of Fillmore, CA

O: 12APR2002 18:21:18 36.7N 121.4W ML=2.0 NCSN WSW of Tres Pinos, CA
O: 12APR2002 19:19:16 36.7N 121.4W ML=2.1 NCSN WSW of Tres Pinos, CA

O: 11APR2002 18:50:18 41.4N 122.1W MD=2.8 NEI NORTHERN CALIFORNIA

PACIFIC NORTHWEST/CANADA

O: 12APR2002 05:45:12 47.4N 123.2W ML=2.3 PGC WSW Seattle WA
O: 11APR2002 22:45:12 47.3N 123.2W ML=2.7 PNSN NW of Olympia, WA

O: 12APR2002 09:54:15 47.5N 121.8W ML=1.0 PNSN SW of North Bend, WA

ROCKY MOUNTAIN AREA

O: 11APR2002 19:26:53 39.0N 111.9W ML=2.7 UUSN NNW of Redmond, UT

EASTERN U.S./CANADA

O: 12APR2002 09:17:41 34.2N 97.6W ML=1.8 TUL JEFFERSON OK

ALASKA

HAWAII

O: 11APR2002 22:24:35 19.8N 155.0W ML=3.3 HVO ENE of Papa`ikou, Hawaii