by Stephanie McGrath.
December’s great Sumatra-Andaman earthquake – the most powerful in more than 40 years and the trigger of a devastating tsunami – shook the ground everywhere on Earth’s surface, scientists have found.
Weeks later the planet was still trembling.
The quake resulted from the longest fault rupture ever observed – 720 to 780 miles, which spread for 10 minutes, also a record. A typical earthquake’s duration would be 30 seconds.
The December quake was the first of its size to be measured and studied by the new worldwide array of digital seismic instruments.