Scientists presented new evidence Monday suggesting that the northeastern corner of the Indian subcontinent is actively colliding with Asia and has the potential to cause a major earthquake risk to one of the most densely populated regions in the world.
The evidence is a result of a new GPS study of Bangladesh, India and Myanmar published first in the Nature Geoscience journal. This is the very first study to use GPS data from Bangladeshi tracking stations and is the latest addition to the long-standing debate over whether the area, which is home to more than 140 million people, is seismically active.
The threat is a subduction zone, the place where two lithospheric plates come together, one riding over the other. All major earthquakes known to man have occurred along such zones. Researchers said that the allegedly active megathrust fault beneath the Indo-Burman mountain ranges, which mark the boundary between the Indian and Eurasian plates, has been accumulating stress for more than 400 years, National Geographic reported.
“Some of us have long suspected this hazard, but we didn't have the data and a model,” lead author Michael Steckler reportedly said. “Now we have the data and a model, and we can estimate the size.”
The accumulated strain between the plates will result in an earthquake likely to be larger than 8.2 in terms of magnitude with the potential of reaching a magnitude of 9 on the Richter scale. “We don’t know how long it will take to build up steam, because we don’t know how long it was since the last one,” Steckler said. “We can’t say it’s imminent or another 500 years. But we can definitely see it building.”
The study also found that this subduction zone was an extension of the same tectonic boundary that caused the 2004 Indian Ocean tsunami, which left at least 230,000 people dead.