Perched atop the notorious Ring of Fire, an arc of fault lines and volcanoes in the Pacific Basin, earthquakes are an almost weekly occurrence in Indonesia. After close analysis of a mammoth earthquake that struck the island of Sumatra this April, scientists in the U.S. say the quake indicates the Indo-Australian tectonic plate is now splitting in two.
The 8.7-magnitude quake that struck the Indonesian island of Sumatra this April sent shockwaves, literally, around the globe.
After extensively studying the quake and its aftermath, scientists say the rupture is unprecedented. It was the biggest slip-strike, or horizontal rather than vertical quake, ever recorded.
Seismologists say the April 11 quake caused four fault lines to rupture almost simultaneously.
Jamie McCaughey is a geologist from the Earth Observatory in Singapore, an institute that studies earthquakes, volcanoes and tsunamis.
He says the recent study in the scientific journal Nature confirms that the Indian-Australian tectonic plate is splitting in two.
“The evidence is very clear that, and what the authors describe is that, the earthquake is really just illustrating a long-term process and teaching us more about it, that the sea floor of the Indian Australian plate is slowly becoming two separate plates and this earthquake illustrated that process unfolding,” said McCaughey.
It is expected to take millions of years for the plate to divide completely, but the study also shows how earthquakes can trigger other quakes, weeks, and even years after they occur.