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Posted by Lowell on November 29, 2001 at 13:05:39:
MID-OCEAN RIDGE/EXTENSIONAL TECTONICS EVENTS BEGIN IN EARNEST SUMMARY As expected, 4-5 days after the strong geomagnetic storm on November
24, 2001, a series of moderate earthquakes have been occurring in
extensional environments (accretional plate boundaries) such as the
East African rift valley and mid-ocean ridges. This is a very common
occurrence and suggests a delayed causal relation between these
earthquakes and strong geomagnetic storms. This report had stated
on November 24 regarding this possibility: "A severe (Kp>=9) geomagnetic storm arrived this morning at
about 05:45 UT. This was a suden commencement storm and severely
degraded to readability of most of the on-line seismograms.
Areas which are sub-solar include regions within 20 degrees longitude
of 90E; anti-solar areas are within 20 degrees longitude of
90W, however the strength of the storm suggests that 30-35 degrees
should be taken about the anti- and sub-solar longitudes to be
included in the seismic watch. ... Regions most vulnerable towards the end of the period
include regions of high heat flow, such as YELLOWSTONE and
So. California near Calexico and Mammoth Lakes CA or MID-OCEAN
RIDGES (in this case the south Indian ridge and the EAST PACIFIC RISE)."
[emphasis added]
Unusual earthquakes in mid-ocean ridges or extensional envoironments have
occurred in the past three days with the following parameters:
O: 29NOV2001 17:06:58 4.3S 104.2W MB=5.0 NEIS CENTRAL EAST PACIFIC RISE
O: 29NOV2001 15:55:31 46.9S 10.6W MB=4.8 NEIS SOUTHERN MID-ATLANTIC RIDGE
O: 27NOV2001 12:50:30 55.6S 27.1W MB=4.7 NEIS SOUTH SANDWICH ISLANDS REGION
O: 27NOV2001 10:07:53 57.8S 25.9W MB=4.5 NEIS SOUTH SANDWICH ISLANDS REGION
O: 28Nov2001 20:32:13 56.3S 24.7W MB=4.2 NEIS SOUTH SANDWICH ISL REGION
O: 28NOV2001 16:24:07 30.7N 112.9W MB=4.3 NEIS GULF OF CALIFORNIA
O: 29NOV2001 10:17:07 53.2N 107.9E Ms=3.9 GSSA LAKE BAYKAL, RUSSIA
O: 29NOV2001 09:43:28 53.3N 107.9E Ms=3.7 GSSA LAKE BAYKAL, RUSSIA
O: 27Nov2001 00:20:29 5.5S 29.0E MB=4.4 NEIS LAKE TANGANYIKA REGION
O: 26NOV2001 13:07:11 2.1N 99.9W MB=4.8 NEIS WEST OF GALAPAGOS ISLANDS
O: 27NOV2001 04:23:37 44.4N 28.0W MB=4.8 NEIS NORTHERN MID-ATLANTIC RIDGE
O: 26NOV2001 01:48 50.0S 154.8E MB=5.1 AGSO Tasman Sea, Macquarie Islands Source on last - Tasman Sea earthquake is:
http://www.seis.com.au/EQ/Earthquakes.html Typically about one such event will occur in any given 3-day period.
For example, in the 4 days prior to the geomagnetic storm on 24 November,
only one earthquake - in the Balleny Islands Mb 4.8) had been located
in extensional regimes by NEIS, so this activity represents a substantial
rate increase over typical background.
Five of the 8 events outside of the South Sandwich Islands have occurred
within 25 degrees longitude of the sub- and anti-solar longitudes
at the time of the storm commencement, this also is expected. The Mb 4.2 in the Northern Gulf of California fit two groupings -
the So. California and the mid-ocean ridge (East Pacific Rise extension)
groups. A minor swarm of earthquakes has also occurred in the Yellowstone
region beginning a few hours after the sudden commencement storm began.
For details of events in this swarm see: http://www.quake.utah.edu/req2webdir/recenteqs/Quakes/quakes0.html
RELATIONS TO GREAT KUNLUN MTS. EARTHQUAKE
Many of these area may have been "set-up" for subsequent activity
by shaking from the Kunlun Mts. earthquake (Ms 8.1 November 14, 2001).
With the exception of the events in the South Atlantic all lie within
or near distances and regions where strong Far-field aftershocks were
expected from the Nov. 14 earthquake: EAST PACIFIC RISE: Distance to Kunlun = 145 degrees
WEST GALAPAGOS : Distance to Kunlun = 141 degrees The FFA forecast had said: "142-146 degrees: ... Galapagos" GULF OF CALIFORNIA : Distance to Kunlun = 109 degrees The FFA forecast had said: "103-107 degrees***: California/Baja border (about 32-34N)" LAKE BAYKAL: Distance to Kunlun = 19 degrees The FFA forecast had said: "17-19 degrees: ... NE China" LAKE TANGANYIKA: Distance to Kunlun = 72 degrees The FFA forecast had said: "71-73 degrees: ... Tanzania, Malawi" TASMAN SEA, South of Australia: Distance to Kunlun = 103 degrees The FFA forecast had said: "103-107 degrees***" ***: The strongest triggering is always expected to be along the
shadow zone boundary between 103-107 degrees from the epicenter." GLOBAL Other events of Mb>=4 recorded since the our last report have
occurred near Central Peru (Mb 4.3); Pakistan (Mb>4); South of the
Kermadec Islands (Mb 4.5, 4.6); in the Minahass Peninsula area of
Sulawesi (Mb 4.7 and 4.1); Taiwan (Mb 4.6) and in the northern Kuril
Islands (Mb 4.2). U.S./CANADA Seismicity throughout the U.S. and Canada since last report has
been relatively quiet. Earthquakes in California of Ml>=2 have occurred
in southern California in the Santa Barbara region (Ml 2.0); South of
Borrego Springs (Ml 2.2) and SE of Calexico (Ml 2.1). The only such event
in northern and Central California occurred near the Geysers with Ml 2.1.
The swarm in Yellowstone is continuing at this writing. MBMG updated
their listing today through November 26. This listing includes several
interesting earthquake not previously identified by other agencies including
a Ml 3.2 and 2.7 event near New Meadows Idaho on Nov. 23 and 24 respectively;
a Ml 2.6 NE of Stanley, Idaho on Nov. 25 and a Ml 2.7 near Bozeman, MT
on November 20. MBMG generally updates their listing every 2-3 weeks.
A Ml 2.2 earthquake was recorded in the New Madrid (Caruthersville, TN)
MO area this morning, the first in the area since Nov. 17 when a Ml 2.2
also hit nearby. The last event in the New Madrid region which was
larger occurred on September 1, 2001 (Ml 2.4). Earthquakes of Ml>=2
have also occurred in eastern Canada in New Brunswick (Ml 2.2) and
near Matane, Quebec (Ml 2.5) in the past several days.
One earthquake of Ml 3.3 has been listed by HVO this morning in the
region of Hawaii, however magnitudes and location of such initial listings
are generally considerably in error. No events of Ml>=3 have been
listed in Alaska by AEIC in the past 24 hours.
Seismicity in the Pacific Northwest and western Canada also appears
to have been relatively quiet since our last report. NEW ZEALAND Two areas in and near New Zealand were listed since the last report
as having moderate earthquake. The first was the Tasman Sea earthquake
south of Australia (Mb 5.1). This earthquake lies at the p-wave shadow
zone boundary from the Kunlun Mts. great earthquake (103 degrees away).
It is the largest earthquake ever recorded within 200 km of this
location, the previous (and only event of Mb>=5 ever recorded in this
area) occurred on July 16, 1961 (Mb 5.0).
The other area was the region south of the Kermadec Islands, N.Z. where
moderate seismicity has been occurring for the past two to three days.
This area is at the s- wave shadow zone boundary from the great Kunlun
earthquake of Nov. 14 (107 degrees distant).
The on-line seismogram is showing a series of as yet unlocated
events (they look like perhaps volcanic tremor at Ruapehu) in the
past several hours. 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 has remained at quiet conditions throughout
the day. A strong M-class solar flare was observed this afternoon
following a weak M-class flare this morning with the following parameters: Flare # START MAX END CLASS 7370 + 0142 0149 0151 M1.1
7530 + 1012 1036 1043 M5.5 An earthquake in the Lake Baykal region was recorded shortly after flare
#7530 began. The earthquake had the following parameters: O: 29NOV2001 10:17:07 53.2N 107.9E Ms=3.9 GSSA LAKE BAYKAL, RUSSIA, For general space weather conditions see: http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20011129events.txt TROPICAL STORMS TROPICAL STORM OLGA Tropical storm Olga continues moving southwestward towards the
Bahamas, Cuba and possibly southern Florida. Olga has been downgraded
to a tropical storm, however could pick up steam in the warmer
waters north of Cuba. A thorough discussion on the possible effects
of Olga on regional seismicity is available in yesterday's report.
Landfall in the Bahamas or Cuba is possible on Sunday or Monday,
Dec 2 or 3. For tracking details see: http://www.wunderground.com/auto/HurricaneSite/tropical/tracking/at200117.html TROPICAL CYCLONE BESSI Tropical cyclone Bessi is currently south of Sumatera and moving SSE,
but is expected to turn to the west and diminish in intensity. At this
time no seismicity is expected to be triggered by Bessi. For a public
advisory see: http://www.wunderground.com/auto/HurricaneSite/tropical/sp200101.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. November 30 is the sixteenth 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 Kermadec MB>=4.0 14 2.0 0.05
Nevada MB>=2.0 22 3.3 0.01
Spain MB>=4.0 35 2.5 0.03
Puerto Rico MB>=4.0 18 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
So.California MB>=0.0 -8 -2.1 0.05 EARTHQUAKE LISTINGS GLOBAL NEW ZEALAND/AUSTRALIA O: 26NOV2001 01:48 50.0S 154.8E MB=5.1 AGSO Tasman Sea, Macquarie Islands
Note (AGSO): This earthquake occurred about 950 km southeast of Hobart, and
about 570 kilometres northweast of Macquarie Island. This
earthquake was located using data supplied by the ASC in Canberra and SRC.
Note (ED): This earthquake lies at the p-wave shadow zone boundary from the
Kunlun Mts. great earthquake (103 degrees away). It is the largest earthquake
ever recorded within 200 km of this location, the previous (and only event
of Mb>=5 ever recorded in this area) occurred on July 16, 1961 (Mb 5.0). O: 29Nov2001 00:21:47 33.2S 179.8W MB=4.6 NEIS SOUTH OF KERMADEC ISLANDS
O: 28Nov2001 05:29:57 33.3S 178.4W MB=4.8 NEIS SOUTH OF KERMADEC ISLANDS
O: 28Nov2001 00:48:36 32.5S 178.4W MB=4.8 NEIS SOUTH OF KERMADEC ISLANDS
O: 27Nov2001 03:50:22 34.0S 179.4W MB=4.1 NEIS SOUTH OF KERMADEC ISLANDS
O: 27Nov2001 02:26:48 33.8S 178.7W MB=5.2 NEIS SOUTH OF KERMADEC ISLANDS
SOUTH PACIFIC ISLANDS
O: 27Nov2001 18:11:36 19.8S 175.5W MB=4.7 NEIS TONGA ISLANDS O: 28Nov2001 12:52:56 24.5S 179.3E MB=3.9 NEIS SOUTH OF FIJI ISLANDS
O: 27Nov2001 23:10:35 23.7S 179.9E MB=5.0 NEIS SOUTH OF FIJI ISLANDS O: 27Nov2001 05:19:08 15.9S 178.0W MB=4.4 NEIS FIJI ISLANDS REGION O: 27Nov2001 01:04:19 15.7S 178.1E MB=4.0 NEIS FIJI ISLANDS O: 27Nov2001 00:00:19 14.9S 177.7W MB=4.0 NEIS FIJI ISLANDS REGION
ASIA
O: 28Nov2001 17:58:25 0.0S 123.0E MB=4.7 NEIS MINAHASSA PEN, SULAWESI O: 28Nov2001 10:43:48 50.5N 154.5E MB=4.2 NEIS KURIL ISLANDS O: 28Nov2001 03:29:46 52.8N 157.4E MB=4.8 NEIS KAMCHATKA PEN, RUSSIA O: 28Nov2001 02:53:53 24.3N 122.7E MB=4.6 NEIS TAIWAN REGION O: 27Nov2001 17:58:55 2.8N 99.3E MB=4.6 NEIS N SUMATERA, INDONESIA O: 27Nov2001 17:56:55 29.6N 81.7E MB=5.0 NEIS NEPAL O: 29NOV2001 10:17:07 53.2N 107.9E Ms=3.9 GSSA LAKE BAYKAL, RUSSIA,
O: 29NOV2001 09:43:28 53.3N 107.9E Ms=3.7 GSSA LAKE BAYKAL, RUSSIA, O: 28NOV2001 17:58:00 0.7N 125.2E SR=5.3 AEIC1 S TONDANO, INDONESIA O: 28NOV2001 09:31:10 5.3N 126.3E SR=4.9 AEIC1 N BITUNG, INDONESIA O: 28NOV2001 09:27:10 10.6S 113.1E SR=4.8 AEIC1 S LUMAJANG, INDONESIA O: 27NOV2001 18:27:00 8.5S 116.0E SR=5.1 AEIC1 NW MATARAM, INDONESIA
O: 27NOV2001 14:25:10 9.2S 116.2E SR=4.9 AEIC1 S PRAYA, INDONESIA O: 27NOV2001 18:19:20 8.6S 114.7E SR=5.1 AEIC1 SE NEGARA, INDONESIA O: 27NOV2001 16:41:50 7.8S 115.8E SR=4.7 AEIC1 N AMLAPURA, INDONESIA
O: 27NOV2001 14:32:00 8.8S 115.6E SR=4.8 AEIC1 S NUSAPENIDA, INDONESIA O: 27NOV2001 15:16:30 9.4S 117.8E SR=5.0 AEIC1 SUMBAWABESAR, INDONESIA
O: 25NOV2001 15:49:00 9.7S 117.1E SR=5.4 AEIC1 SE SELONG, INDONESIA O: 27NOV2001 05:40:20 11.5S 117.3E SR=5.4 AEIC1 SW WAIKABUBAK, INDONESIA O: 27NOV2001 04:44:00 8.7S 111.7E SR=4.8 AEIC1 TRENGGALEK, INDONESIA
O: 26NOV2001 21:49:20 9.9S 125.7E SR=5.3 AEIC1 SE ATAMBUA, INDONESIA O: 26NOV2001 17:29:40 11.4S 115.0E SR=5.1 AEIC1 S DENPASAR, INDONESIA O: 26NOV2001 13:32:40 9.3S 115.5E SR=4.9 AEIC1 S NUSAPENIDA, INDONESIA O: 25NOV2001 20:45:20 9.5S 114.1E SR=5.0 AEIC1 SW NEGARA, INDONESIA
O: 25NOV2001 10:37:50 9.9S 114.0E SR=4.8 AEIC1 S NEGARA, INDONESIA CENTRAL/SOUTH AMERICA O: 29NOV2001 13:02:39 12.7N 88.6W ML>4.0 SIS El Salvador O: 29NOV2001 05:40:37 9.9N 86.2W MC=4.3 SIS COSTA RICA C.A. O: 29NOV2001 05:40:47 11.5N 85.0W MC=3.4 CASC COSTA RICA, C.A. O: 29NOV2001 08:39:22 9.3N 84.2W MC=3.2 CASC Costa Rica, C.A. O: 29NOV2001 09:43:59 10.7N 85.5W MC=3.4 CASC Costa Rica, C.A. O: 24NOV2001 18:55:01 32.4S 71.5W ML=3.9 DGF N of PAPUDO, CHILE
O: 29NOV2001 06:26:15 10.3S 74.7W MB=4.3 NEIS CENTRAL PERU
EUROPE/AFRICA/MIDDLE EAST O: 27Nov2001 00:20:29 5.5S 29.0E MB=4.4 NEIS LAKE TANGANYIKA REGION O: 29NOV2001 04:47:13 38.1N 20.1E ML=3.4 NOA GREECE
O: 29NOV2001 04:57:40 38.0N 20.2E ML=3.6 NOA GREECE OCEANIA O: 28Nov2001 20:32:13 56.3S 24.7W MB=4.2 NEIS SOUTH SANDWICH ISL REGION O: 29NOV2001 17:06:58 4.3S 104.2W MB=5.0 NEIS CENTRAL EAST PACIFIC RISE O: 29NOV2001 15:55:31 46.9S 10.6W MB=4.8 NEIS SOUTHERN MID-ATLANTIC RIDGE U.S/CANADA CALIFORNIA/NEVADA O: 28NOV2001 22:03:31 34.3N 119.7W MC=2.0 SCSN SSE of Santa Barbara, CA
O: 29NOV2001 05:06:14 32.5N 116.9W ML=2.1 SCSN ESE of San Ysidro, CA
O: 29NOV2001 15:49:18 32.8N 116.0W ML=1.9 SCSN N of Ocotillo, CA O: 29NOV2001 13:52:46 38.8N 122.8W ML=2.1 NCSN NW of The Geysers, CA O: 29Nov2001 00:37:42 38.9N 123.6W ML=3.1 NEIS NEAR COAST OF N CALIF. ROCKY MOUNTAIN AREA O: 29NOV2001 06:57:10 43.6N 111.1W ML=2.0 USBR SSW of Driggs, ID O: 15NOV2001 02:16:26 43.6N 110.5W ML=1.9 MBMG 30 km NE of Jackson, WY,
O: 15NOV2001 02:26:48 43.6N 110.5W ML=1.8 MBMG 30 km NE of Jackson, WY, O: 14NOV2001 14:09:05 44.2N 115.0W ML=2.5 MBMG near Stanley, ID O: 25NOV2001 08:56:10 44.3N 114.6W ML=2.6 MBMG 25 km NE of Stanley, ID O: 22NOV2001 05:14:36 44.8N 111.1W ML=1.0 MBMG Hebgen Lake region, MT
O: 20NOV2001 08:04:03 44.8N 111.5W ML=1.5 MBMG S Madison Valley, MT
O: 22NOV2001 08:07:16 44.8N 111.3W ML=1.4 MBMG S Madison Range, MT
O: 26NOV2001 06:05:58 44.8N 111.0W ML=1.0 MBMG Hebgen Lake region; UUSS, MT O: 13NOV2001 23:39:14 44.8N 111.5W ML=2.2 MBMG S Madison Valley, MT O: 24NOV2001 13:41:37 44.9N 116.4W ML=2.7 MBMG 25 km NW of Grangeville, ID
O: 23NOV2001 22:00:58 44.9N 116.3W ML=3.2 MBMG near New Meadows, ID O: 13NOV2001 01:09:11 45.0N 108.5W ML=1.9 MBMG 50 km SE of Bridger, MT O: 17NOV2001 02:40:10 45.3N 115.5W ML=2.3 MBMG 40 km ESE of Cascade, ID O: 21NOV2001 17:50:17 46.2N 111.8W ML=2.0 MBMG 20 km E of Boulder, MT
O: 21NOV2001 09:22:35 46.2N 111.8W ML=2.1 MBMG 15 km E of Boulder, MT O: 18NOV2001 11:27:01 47.2N 113.1W ML=1.5 MBMG 25 km E of Seeley Lake, MT
O: 17NOV2001 18:31:06 47.2N 113.1W ML=1.1 MBMG 25 km E of Seeley Lake, MT O: 25NOV2001 03:55:35 47.5N 115.5W ML=1.5 MBMG 10 km W of Thompson Falls, MT O: 20NOV2001 21:55:07 47.6N 113.5W ML=1.1 MBMG 15 km NE of Condon, MT O: 26NOV2001 11:11:52 47.7N 113.8W ML=1.8 MBMG 20 km S of Swan Lake, MT O: 17NOV2001 04:56:39 47.7N 113.7W ML=1.2 MBMG 20 km S of Swan Lake, MT O: 14NOV2001 02:07:10 47.8N 114.7W ML=1.2 MBMG 10 km SW of Niarada, MT O: 23NOV2001 11:22:38 47.9N 115.3W ML=1.3 MBMG 20 km SW of Happys Inn, MT O: 22NOV2001 03:36:12 49.3N 115.9W ML=2.2 MBMG S British Columbia
EASTERN U.S./CANADA
O: 29NOV2001 1:55:25 36.1N 89.7W ML=2.2 CERI SW of Caruthersville, TN
Note: This earthquake occurred at 107 degrees from the great Kunlun
earthquake in an area and distance where FFA were expected. It is the
largest event in the New Madrid fault zone since Nov. 17 when another
Ml 2.2 occurred. The last event in the New Madrid region which was
larger than this occurred as a Ml 2.4 on September 1, 2001.
This event also lies exactly anti-solar to the commencement of the
severe geomagnetic storm on November 24. A seismic watch is in effect
for regions within 20 degrees longitude of 90W until Dec. 1. O: 27NOV2001 06:14:18 45.7N 75.5W MN=1.2 GSC 20 km NW from Buckingham, Que. O: 25NOV2001 21:00:41 49.3N 66.6W MN=2.4 GSC 82 km NE from Matane, Que. O: 25NOV2001 06:00:03 45.2N 80.0W MN=1.2 GSC 20 km S from Parry Sound, Ont.
O: 25NOV2001 02:50:02 45.2N 80.0W MN=1.4 GSC 20 km S from Parry Sound, Ont. O: 25NOV2001 04:35:06 47.0N 66.5W MN=2.2 GSC Miramichi, N. B.
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