Lurking under Bangladesh: The next great earthquake?

July 14, 2011

After the recent great quakes that have swept away entire coastlines and cities in Japan, Haiti and Sumatra, scientists are now looking hard at the nation that may suffer the gravest threat of all: Bangladesh. A new documentary from the Earth Institute follows seismologists as they trace signs of deeply buried active faults, past movements of the earth, and sudden, catastrophic river-course changes.

With more than 160 million people, Bangladesh is the most crowded place on earth, and one of the poorest–and it is growing fast. It sits on the world’s largest river delta, close to sea level, which exposes it to tsunamis and the possibility of rivers jumping their banks in the event of earthquake. And, it is furiously putting up bridges and multistory buildings that increase its vulnerability. Scientists have come to recognize that it sits at the juncture of several active tectonic plate boundaries–including the tail end of the one that caused the 2004 Sumatra tsunami that killed over 200,000 people, 1,300 miles south. Syed Humayun Akhter, a seismologist at the Dhaka University Earth Observatory, warns that an earthquake near the crowded capital could dwarf other modern tragedies.

This year saw the start of a five-year, $5 million project to chart the hazards, funded by the U.S. National Science Foundation’s Partnerships for International Research and Education program. Led by seismologists at Columbia University’s Lamont-Doherty Earth Observatory in conjunction with Dhaka University, the team includes specialists from Vanderbilt University, the University of Minnesota and Queens College, and researchers in Germany, Italy and India. The scientists have been upgrading a network of seismometers that registers tiny tremors far below. This allows them to better map active faults buried under as much as 12 miles of sand and mud laid down by the mighty rivers that drain the Himalayas. They are also drilling some 250 wells near riverbeds to take sediment samples. These, they hope, will reveal the scope and timing of past earthquakes and river-course shifts that may have wiped out large swaths of countryside–though at times when population and infrastructure were far less dense. The goal is to give Bangladeshi scientists and leaders the tools they need to understand, and minimize, the risks.

“Like the great delta on which Bangladesh is confined, we find ourselves at a strategic confluence between earth science, natural hazard engineering and international relations,” says Leonardo Seeber, a Lamont seismologist working on the project. This month, Lamont seismologist Michael Steckler, the project’s lead investigator, was in Washington to help launch a new program run jointly by NSF and the U.S. Agency for International Development designed to advance such collaborations with developing countries. “This partnership will help particularly with the application of science, technology and innovation to accelerate global development, with huge benefits for industrialized and developing countries alike,” said John P. Holdern, director of the White House Office of Science and Technology Policy, speaking at the event.