Far North Science

News, research and natural acts from Alaska

March 22nd, 2007
Updated April 1, 2007 @ 12:54 pm

Next Big Quake: ‘Locked and Loaded’

USGS map showing location of the Sumatran earthquake
Credit: USGS

The devastating 2004 Sumatra-Andaman earthquake and the ocean-wide tsunami that followed killed almost 230,000 people in the third most powerful temblor ever measured on Earth.

It struck along one of the world’s great engines for producing large quakes — the subduction boundary between tectonic plates in the Indian Ocean. Yet scientists didn’t realize at the time that this particular area off the west coast of Indonesia posed such a terrible hazard.

“One lesson we should take away from the Sumatra-Andaman earthquake is that every subduction zone is potentially locked, loaded, and dangerous,” wrote geophysicist Robert McCaffrey in “The Next Great Earthquake,” published this week in the journal of Science.

With an immense tectonic collision grinding away only 20 miles beneath the Alaska’s southern rim, is there also a lesson for the Far North?

Be ready, Alaskans. Be very ready.

“We should not rule out completely another M9 (earthquake) in the not-so distant future,” McCaffrey said in an email message. “We don’t know the repeat time and the variability in that time.”

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March 22nd, 2007
Updated April 1, 2007 @ 12:56 pm

Oldest Ocean crust: 3.8 billion years

A photo of 3.8-billion-year-old rock in Greenland
Old Rocks in Greenland
Credit: AAAS

They might not look like much, but these weathered rocks have been chilling for a long time along the east coast of Greenland. Scientists believe they may be the oldest chunk of the Earth’s crust ever found.

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