San Andreas-like fault found in eastern U.S.
Fault, from New York to Alabama, may be 500 million years old
 | The fault is invisible from the surface, but magnetic surveys from the air see it clearly, represented in the white line. "It's almost a needle in a haystack," said Mark Steltenpohl of the University of Alabama at Auburn. |
For 30 years geologists have been puzzled by a remarkably straight magnetic line that runs between New York and Alabama along the Appalachians.
A more recent aerial magnetic survey of the Alabama end of the line suggests that it's probably a 500-million-year-old San Andreas-style fault that appears to have slipped 137 miles to the right in the distant past.
If so, it's no surprise that the most dangerous part of the eastern Tennessee seismic zone is right next to part of this magnetic line and has the second-highest earthquake frequency in the eastern United States.
"It's most likely a strike-slip fault," said Mark Steltenpohl of the University of Alabama
at Auburn. "But it's all buried."
The fault is invisible from the surface and there is very little information about it because no one has actually drilled down through it to investigate, Steltenpohl told Discovery News.
That would, in fact, be pretty hard to do, since the fault zone is very narrow and it would be hard to find with a drill using just magnetic maps to set up a drill rig.
"It's almost a needle in a haystack," said Steltenpohl."It's most likely a strike-slip fault," said Mark Steltenpohl of the University of Alabama
at Auburn. "But it's all buried." The fault is invisible from the surface and there is very little information about it because no one has actually drilled down through it to investigate, Steltenpohl told Discovery News.
That would, in fact, be pretty hard to do, since the fault zone is very narrow and it would be hard to find with a drill using just magnetic maps to set up a drill rig.
"It's almost a needle in a haystack," said Steltenpohl.
======================
Iceland's volcano still rumbling
REYKJAVIK, Iceland, June 2 (UPI) -- A geophysicist in Iceland says it is too early to declare an end to the latest eruption of the Eyjafjallajokull volcano.
Geophysicist Magnus Tumi Gudmundsson says there are still tremors and seismic activity which could mean another eruption, the Iceland Review reported Wednesday.
Iceland's Soil Conservation Service has been working on a plan to keep the volcanic ash from spreading.
Director Sveinn Runolfsson says approximately 3.4 percent of Iceland has extensive ash accumulation.
He estimates it will cost $781,000 to bind the ash by sowing the fields and spreading fertilizer.
For the past few days, winds have been blowing from the southeast, carrying ash from the eruption site to the area around the capital of Reykjavik.
16 evacuated from Northern Islands
The U.S. Fish & Wildlife has evacuated 16 people-mostly its scientists-from the Northern Islands following the eruption of an active submarine volcano south of Sarigan Friday noon.
Press secretary Angel Demapan told Saipan Tribune yesterday that seven U.S. Fish & Wildlife personnel were picked up from Sarigan Sunday afternoon and brought to Saipan.
Five individuals from Alamagan and four from Pagan were removed to Saipan yesterday afternoon. It's not clear how many of the nine are Northern Islands residents, according to Demapan.
He said they called off the evacuation operation for the nine in Alamagan and Pagan on Sunday afternoon because visibility had cleared up, giving the scientists time to make further observations.
According to the Emergency Management Office, the U.S. Fish and Wildlife used a fixed wing aircraft and a helicopter to extract 16 personnel from Sarigan and Northern Islands.
EMO said the extraction continued yesterday.
EMO said the Alaska Volcanic Observatory and the National Weather Service Guam will continue to assist with their own assets to monitor the area.
The EMO's Crisis Management Team stood down at 3:45pm Sunday.
EMO said consultations with U.S. Fish and Wildlife, AVO, NWS and National Incident Management Organization is ongoing.
Gov. Benigno R. Fitial has declared a state of disaster emergency in the CNMI following the submarine volcano eruption south of Sarigan.
Fitial declared Sarigan unsafe for human habitation and restricted all travel to the island, with the exception of scientific expeditions.
According to EMO, continuing volcanic activity is on-going in the area south of Sarigan, based on seismic activity and visual observations, "presenting a continuing threat of adverse impact in the waters and air space south of Sarigan island."
Sarigan, an island 175 kilometers (109 miles) north of Saipan, is a stratovolcano with no known historic eruptions. It was used as a copra plantation prior to World War II and is currently uninhabited.
According to the USGS, volcanic activity observed on Thursday, May 27, south of Sarigan Island has increased, and the Guam Weather Forecast Office reported that recent satellite images indicate that the affected area is about twice the size of Sarigan Island.
It quoted an observer from the EMO that overflew and photographed an elongated patch of discolored ocean water and possible light-colored floating debris about 6-7 miles south of Sarigan on Thursday. At that time, the area of discoloration and debris extended over about a mile. Successive satellite images indicate that this is a point-source that has dramatically expanded in breadth. The activity appears to be centered about 6-7 miles south of Sarigan, probably on the southern extension of the submarine ridge upon which Sarigan is constructed.
"Submarine eruptions are not uncommon in the Marianas Islands; mariners in the area should remain alert for floating debris and avoid areas of strongly discolored or disturbed water. Near-sea level eruptions can be dangerous producing ash laden explosions, ash and ballistic fallout, and water waves. AVO maintains no monitoring equipment on these submarine volcanoes and therefore warning of eruptive activity is not possible," the USGS said.
http://www.saipantribune.com/newsstory.aspx?newsID=100114&cat=1
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BAJA CALIFORNIA, MEXICO
Geographic coordinates: 32.169N, 115.178W
Magnitude: 4.1 Ml
Depth: 32 km
Universal Time (UTC): 2 Jun 2010 16:07:49
Time near the Epicenter: 2 Jun 2010 09:07:49
Local standard time in your area: 2 Jun 2010 10:07:49
Location with respect to nearby cities:
15 km (9 miles) SSW (205 degrees) of Guadalupe Victoria, Baja California, Mexico
============
revised.
Region: NEW BRITAIN REGION, P.N.G.
Geographic coordinates: 6.209S, 149.338E
Magnitude: 5.8 Mw
Depth: 51 km
Universal Time (UTC): 2 Jun 2010 09:28:56
Time near the Epicenter: 2 Jun 2010 19:28:56
====================
SOUTHERN XINJIANG, CHINA
Geographic coordinates: 38.250N, 75.840E
Magnitude: 4.3 Mb
Depth: 144 km
Universal Time (UTC): 2 Jun 2010 16:41:28
Time near the Epicenter: 3 Jun 2010 00:41:28
Local standard time in your area: 2 Jun 2010 10:41:28
Location with respect to nearby cities:
138 km (86 miles) S (187 degrees) of Kashi, Xinjiang, China
214 km (133 miles) ESE (116 degrees) of Karakul, Tajikistan
=============
VANUATU
Geographic coordinates: 13.682S, 166.421E
Magnitude: 5.6 Mw
Depth: 35 km
Universal Time (UTC): 2 Jun 2010 18:51:08
Time near the Epicenter: 3 Jun 2010 05:51:08
Local standard time in your area: 2 Jun 2010 12:51:08
Location with respect to nearby cities:
220 km (136 miles) NNW (339 degrees) of Santo (Luganville), Vanuatu
======================
SOUTHERN ALASKA
Geographic coordinates: 61.036N, 160.886W
Magnitude: 3.5 Ml
Depth: 51 km
Universal Time (UTC): 1 Jun 2010 17:31:30
Time near the Epicenter: 1 Jun 2010 09:31:30
Local standard time in your area: 1 Jun 2010 11:31:30
Location with respect to nearby cities:
8 km (5 miles) SSE (151 degrees) of Tuluksak, AK
=============
EASTERN HONSHU, JAPAN
Geographic coordinates: 39.050N, 140.804E
Magnitude: 4.8 Mb
Depth: 11 km
Universal Time (UTC): 2 Jun 2010 22:39:26
Time near the Epicenter: 3 Jun 2010 07:39:26
Local standard time in your area: 2 Jun 2010 16:39:26
Location with respect to nearby cities:
79 km (49 miles) SSW (201 degrees) of Morioka, Honshu, Japan
89 km (55 miles) N (356 degrees) of Sendai, Honshu, Japan
============
OFFSHORE BIO-BIO, CHILE
Geographic coordinates: 36.807S, 73.465W
Magnitude: 4.7 Mb
Depth: 35 km
Universal Time (UTC): 3 Jun 2010 04:01:33
Time near the Epicenter: 3 Jun 2010 00:01:33
Local standard time in your area: 2 Jun 2010 22:01:33
Location with respect to nearby cities:
37 km (23 miles) W (274 degrees) of Concepcion, Chile
220 km (136 miles) SW (227 degrees) of Talca, Chile
=============
JAN MAYEN ISLAND REGION
Geographic coordinates: 70.777N, 14.534W
Magnitude: 5.4 Mb
Depth: 10 km
Universal Time (UTC): 3 Jun 2010 04:32:43
Time near the Epicenter: 3 Jun 2010 03:32:43
Local standard time in your area: 2 Jun 2010 22:32:43
Location with respect to nearby cities:
277 km (172 miles) E (80 degrees) of Ittoqqortoormiit (Scoresbysund), Greenld
801 km (498 miles) NNE (20 degrees) of REYKJAVIK, Iceland
=============
CASPIAN SEA, OFFSHORE AZERBAIJAN
Geographic coordinates: 40.707N, 50.394E
Magnitude: 4.4 Mb
Depth: 38 km
Universal Time (UTC): 3 Jun 2010 04:53:31
Time near the Epicenter: 3 Jun 2010 09:53:31
Local standard time in your area: 2 Jun 2010 22:53:31
Location with respect to nearby cities:
57 km (36 miles) NE (49 degrees) of BAKU, Azerbaijan
===============
SOUTHERN QINGHAI, CHINA
Geographic coordinates: 33.282N, 96.072E
Magnitude: 5.2 Mb
Depth: 10 km
Universal Time (UTC): 3 Jun 2010 05:35:43
Time near the Epicenter: 3 Jun 2010 13:35:43
Local standard time in your area: 2 Jun 2010 23:35:43
Location with respect to nearby cities:
259 km (161 miles) NNW (335 degrees) of Qamdo, Xizang (Tibet)
=================
SOUTHERN QINGHAI, CHINA
Geographic coordinates: 33.318N, 96.220E
Magnitude: 4.4 Mb
Depth: 10 km
Universal Time (UTC): 3 Jun 2010 05:46:59
Time near the Epicenter: 3 Jun 2010 13:46:59
Local standard time in your area: 2 Jun 2010 23:46:59
Location with respect to nearby cities:
257 km (160 miles) NNW (339 degrees) of Qamdo, Xizang (Tibet)
=============
NORTHERN EAST PACIFIC RISE
Geographic coordinates: 8.396N, 103.815W
Magnitude: 4.7 Mb
Depth: 10 km
Universal Time (UTC): 3 Jun 2010 06:39:17
Time near the Epicenter: 2 Jun 2010 23:39:17
Local standard time in your area: 3 Jun 2010 00:39:17
Location with respect to nearby cities:
1031 km (640 miles) SSW (205 degrees) of Acapulco, Guerrero, Mexico
===============
KURIL ISLANDS
Geographic coordinates: 44.845N, 147.851E
Magnitude: 4.4 Mb
Depth: 43 km
Universal Time (UTC): 3 Jun 2010 07:38:02
Time near the Epicenter: 3 Jun 2010 19:38:02
Local standard time in your area: 3 Jun 2010 01:38:02
Location with respect to nearby cities:
43 km (27 miles) S (183 degrees) of Kuril'sk, Kuril Islands
346 km (215 miles) NE (52 degrees) of Kushiro, Hokkaido, Japan
===========
NORTHERN MID-ATLANTIC RIDGE
Geographic coordinates: 13.577N, 44.835W
Magnitude: 5.0 Mb
Depth: 10 km
Universal Time (UTC): 3 Jun 2010 07:43:42
Time near the Epicenter: 3 Jun 2010 04:43:42
Local standard time in your area: 3 Jun 2010 01:43:42
Location with respect to nearby cities:
1264 km (785 miles) NE (40 degrees) of CAYENNE, French Guiana
==============
NORTHERN SUMATRA, INDONESIA
Geographic coordinates: 4.803N, 95.839E
Magnitude: 5.4 Mw
Depth: 82 km
Universal Time (UTC): 3 Jun 2010 09:24:16
Time near the Epicenter: 3 Jun 2010 16:24:16
Local standard time in your area: 3 Jun 2010 03:24:16
Location with respect to nearby cities:
96 km (59 miles) SE (144 degrees) of Banda Aceh, Sumatra, Indonesia
==============
JAN MAYEN ISLAND REGION
Geographic coordinates: 70.746N, 14.431W
Magnitude: 4.8 Mb
Depth: 10 km
Universal Time (UTC): 3 Jun 2010 10:16:15
Time near the Epicenter: 3 Jun 2010 09:16:15
Local standard time in your area: 3 Jun 2010 04:16:15
Location with respect to nearby cities:
280 km (174 miles) E (81 degrees) of Ittoqqortoormiit (Scoresbysund), Greenld
==========
IZU ISLANDS, JAPAN REGION
Geographic coordinates: 30.199N, 139.070E
Magnitude: 4.0 Mb
Depth: 292 km
Universal Time (UTC): 3 Jun 2010 16:51:03
Time near the Epicenter: 4 Jun 2010 01:51:03
Local standard time in your area: 3 Jun 2010 10:51:03
Location with respect to nearby cities:
328 km (204 miles) SSW (192 degrees) of Hachijo-jima, Izu Islands, Japan
==========
SOUTHERN CALIFORNIA
Geographic coordinates: 32.692N, 115.919W
Magnitude: 4.1 Ml
Depth: 5 km
Universal Time (UTC): 3 Jun 2010 18:10:03
Time near the Epicenter: 3 Jun 2010 11:10:03
Local standard time in your area: 3 Jun 2010 12:10:03
Location with respect to nearby cities:
9 km (6 miles) SE (126 degrees) of Ocotillo, CA
==========
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