An earthquake in Sumatra in April was caused by up to five faults in the tectonic plates under the ocean floor a new study said.
The 8.6-magnitude earthquake, the 11th largest since 1900, saw the faults acting in concert and sliding sideways to create a series of massive ruptures.
Researchers believe that this could be an early sign of the splitting of the Indo-Australian plate underneath the island.
“For decades, we’ve known this Indo-Australian plate is deforming internally and it’s not really acting like a rigid body,” said Keith Koper, a study author and an associate professor of geophysics at the University of Utah, reported Discovery News.
“We think this will ultimately become a plate boundary, but we have to see what the earth decides.”
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Yet depsite the power of the quake, reported GlobalPost, there was no tsunami due to the nature of what are called "slip-strike" earthquakes that move vertically.
These are less deadly than "subduction" quakes that tend to move horizontally.
The 2004 earthquake that caused the tsunami in Indonesia and Thailand was a result of the latter type of earthquake.
Bloomberg said that the April quake lasted for a whopping two minutes and 40 seconds due to the number of consecutive eruptions.
The fifth fault that cracked open caused a 8.2-magnitude aftershock.
The study was published in the journal Nature.