2 Earthquakes Strike Off Southern California Coast
Two moderate earthquakes have struck under the ocean near the Channel Islands off the Southern California coast.
The U.S. Geological Survey reports a magnitude 4.5 earthquake struck the sea floor about 14 miles east of San Nicolas Island at 2:45 p.m Sunday.
A magnitude 3.6 quake hit three minutes later in the same spot, 56 miles west of Santa Catalina Island, in an area where the sea floor is about 2,000 feet below the surface.
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Tsunami Strikes American Samoa After 8.3-Magnitude Quake
A tsunami swept into Pago Pago, American Samoa, shortly after an earthquake with a preliminary magnitude of 8.3 erupted in the area. There were no immediate reports of injuries or structural damage Tuesday.
Fili Sagapolutele, who works at the Samoa News, says the water flowed inland about 100 yards before receding, leaving some cars stuck in the mud.
The Pacific Tsunami Warning Center in Honolulu issued a tsunami warning for American Samoa and other areas of the Pacific, including New Zealand. A tsunami watch was posted for other areas, including Hawaii and the Marshall Islands.
There are reports that some beaches in Hawaii are being closed as a precaution. Police are at the Pacific Tsunami Warning Center to offer protection and assistance in the event that a large wave forms.
American Samoa, a group of islands, is a U.S. territory located in the South Pacific, about 2,300 miles south of Hawaii. American Samoa is slightly larger than Washington, D.C., with a population of 65,628. The population of Pago Pago is approximately 11,000.
9 Earthquakes Reported In Central Oklahoma
More rumblings underground, all in the same location, have been reported as earthquakes by the Oklahoma Geological Survey in Norman, bringing the total to 9 separate earthquakes in the last 24 hours in the state, the U.S. Geological Survey reports today.
All but one of the earthquakes was reported in eastern Oklahoma County, according to the U.S. Geological Survey. The other quake one was reported northeast of Ada early Thursday.
The largest earthquake was registered as 3.7 magnitude on the Richter scale Thursday night in Jones.
No damages have been reported.
The last quake in the eastern Oklahoma County area was recorded at 10:30 p.m. Thursday on the north and northeast side of Jones, reading 2.4 magnitude on the Richter scale.
In the same location at 10:15 p.m. on the north and northeast side of Jones, an earthquake reading 2.3 magnitude on the Richter scale, according to the survey.
The survey reports the largest was at 9:09 p.m. Thursday, a 3.7 magnitude earthquake was felt in the same area.
Mega-quake Could Strike Near Seattle
Using sophisticated seismometers and GPS devices, scientists have been able to track minute movements along two massive tectonic plates colliding 25 miles or so underneath Washington state’s Puget Sound basin. Their early findings suggest that a mega-earthquake could strike closer to the Seattle-Tacoma area, home to some 3.6 million people, than was thought earlier.
The deep tremors, which humans can’t feel, occur routinely every 15 months or so and can continue for more than two weeks before they die back to undetectable levels.
The instruments are detecting an inch or two of movement — known as “episodic tremor and slip” — as the Juan de Fuca plate grinds and sinks beneath the North American plate.
Closer to the surface, the two plates are locked together.
When they snap, scientists say, it could produce a massive 9.0 or greater earthquake and a tsunami.
By comparison, the largest earthquake ever recorded was 9.5, in Chile in 1960.
The largest in North America was the 9.2 Great Alaska earthquake in 1964, which spawned a tsunami that struck the Northwest coast.
The 1906 San Francisco earthquake, which killed 750 to 2,500 people, was estimated to be an 8.3.
Whereas the scientists once predicted that a mega-earthquake would be centered just off the Northwest coast, now — using data from the tremors research — they say that it could be 30 miles or more inland,under the Olympic Peninsula, which lies to the west of Seattle and Tacoma across Puget Sound.
“The closer you are to the source, the stronger the shaking,” said Steve Malone, a research professor emeritus at the University of Washington.
Two Earthquakes Strike Indian Ocean Region, Japan
Two potentially destructive earthquakes struck minutes apart in the Indian Ocean and Japan today, generating tsunami alerts for India, Myanmar, Indonesia, Thailand, Bangladesh and Japan.
The larger of the two quakes was a magnitude-7.6 temblor that hit the Andaman Islands in the Indian Ocean. It was followed less than 15 minutes later by a 6.6-magnitude quake in Japan southwest of Tokyo.
The tsunami watch was later canceled, the U.S. Pacific Tsunami Warning Center said, adding that no significant tsunami was generated. The alert was in effect for as long as three hours after the quake struck parts of India, Myanmar, Indonesia, Thailand and Bangladesh, the Japan Meteorological Agency said.
The Andaman quake struck at a depth of 33 kilometers 21 miles at about 1:55 a.m. local time and was centered 260 kilometers north of Port Blair in the Andaman Islands, or about 825 kilometers west of Bangkok, the U.S. Geological Survey said.
A magnitude-9.1 earthquake that hit off the coast of Aceh in northern Sumatra in December 2004 triggered a tsunami that swept across the Indian Ocean, leaving more than 229,000 dead or missing from Southeast Asia to eastern Africa.
Quake, Tsunami Potential High On West Coast
Scientists have underestimated the potential for a giant quake and tsunami that could swamp much the U.S. northwest and Canadian west coasts, British and U.S. researchers said on Monday.
Geological evidence suggests there have been earthquakes in the past that were even stronger than a magnitude 9.2 quake — the second-biggest ever recorded — which caused a 42-foot-high (12-meter-high) tsunami in the Gulf of Alaska in 1964, they said.
“Our data indicate that two major earthquakes have struck Alaska in the last 1,500 years and our findings show that a bigger earthquake and a more destructive tsunami than the 1964 event are possible in the future,” Ian Shennan, a professor of geography at Britain’s Durham University, who led the study, said in a statement.
“The region has been hit by large, single-event earthquakes and tsunamis before, and our evidence indicates that multiple and more extensive ruptures can happen.”
For their study, the teams at Durham, the University of Utah and Plafker Geohazard Consultants studied subsoil samples and sediments from the Alaskan coast and found evidence of major disasters 900 years ago and 1,500 years ago.
Mysterious Tremors Detected On San Andreas Fault
Scientists have detected a spike in underground rumblings on a section of California’s San Andreas Fault that produced a magnitude-7.8 earthquake in 1857.
What these mysterious vibrations say about future earthquakes is far from certain. But some think the deep tremors suggest underground stress may be building up faster than expected and may indicate an increased risk of a major temblor.
Magnitude-4.1 Quake Shakes Already-shaken L.A.
Los Angeles has been shaken by another moderate earthquake, a few miles from the epicenter of Sunday’s shaker. No immediate reports of injuries or damage.
The U.S. Geological Survey says it’s not certain whether it’s an aftershock from Sunday’s magnitude-4.7 temblor or a separate quake.
The magnitude-4.1 quake was centered about 2 miles from Hawthorne and 10 miles from downtown L.A., at a depth of 7.5 miles.
5.0 Magnitude Earthquake Strikes Los Angeles
The U.S. Geological Survey says a magnitude 5.0 quake has hit the Los Angeles area.
The quake was centered 1 mile southwest of Los Angeles, near LAX airport and was 8.4 miles deep. A spokesman for the Los Angeles Fire Department said there were no immediate reports of damage or injury.
Disaster Prediction: Tsunami Just the Beginning of Earthquake Supercycle, Say Scientists
Massive earthquakes in the Indian Ocean off the coast of Sumatra are just the beginning. Researchers expect a 30-year cycle of mega-quakes like the one that caused the 2004 tsunami.
How can researchers predict earthquakes? By studying coral reefs in the region. Not only are coral reefs many centuries old, but their shape is a direct response to water levels. After a series of earthquakes, usually the reef winds up higher or lower than it was before – and any part of it that’s exposed to air dies.
Scientists studying Sumatran reefs say the coral there have experienced massive die-offs as well as new horizontal growth about every two hundred years. Moreover, these changes happened in fits and starts over phases of about 30 – 100 years. That suggests the area experiences what’s called an “earthquake supercycle” for several decades every two centuries.
Last year’s 8.4 quake off the coast of Sumatra is probably the first quake in a new supercycle, since the last big die-off in the coral reefs took place in 1833. Other quake cycles hit in 1374, 1596, 1675, and 1797.
Geophysicist Yehuda Bock co-authored a study published in Nature last week that asserted the recent Sumatra quakes were just the beginning. According to Science News:
