(CBS SF) – A massive 7.9 magnitude earthquake Monday in the Aleutian Islands was quickly followed by smaller 5.9 and 6.0 quakes closer to land.
The original quake set off a Tsunami warning after striking deep in the water east of Little Sitkin Island. That was quickly followed by a handful of smaller quakes closer to land. Those tremors ranged in size from magnitude 3.7 to 6.0. All were centered at least 100 kilometers beneath the Earth’s surface.
A magnitude 6.9 earthquake struck the area around 6 p.m. Pacific Time.
Seismographs originally measured the initial quake as a 7.1 but the U.S. Geological Survey quickly upgraded that number to an 7.9. That’s a departure from the usual pattern where quakes are more often downgraded.
REAL-TIME ALASKA TSUNAMI INFORMATION: http://wcatwc.arh.noaa.gov/
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Another massive quake registering 6.9 struck just before the Alaska quake, this one on the polar opposite side of the ocean, north of New Zealand.