Is the Next Great Earthquake Lurking Under Bangladesh?

After the recent great earthquakes that have swept away entire coastlines and cities in Japan, Haiti, and Sumatra, Lamont scientists are looking hard at the nation that may suffer the gravest threat of all: Bangladesh.

With more than 160 million people, Bangladesh is the most crowded place on Earth. It is also one of the poorest, and it is growing fast. It sits on the world’s largest river delta, close to sea level, conditions that expose it to tsunamis and the possibility of rivers jumping their banks in the event of an earthquake. And, it is furiously putting up bridges and multistory buildings that increase its vulnerability. Scientists have come to recognize that Bangladesh 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. Syed Humayun Akhter, a seismologist at the Dhaka University Earth Observatory, warns that an earthquake near the crowded capital city of Dhaka could dwarf other modern tragedies.

Lamont seismologists Leonardo Seeber and Michael S. Steckler, and graduate student Eleanor Ferguson discuss their research in Bangladesh. In 2013, this became the featured video in the American Museum of Natural History’s Hall of Planet Earth.

A new five-year, $5 million project to chart the hazards, funded by the National Science Foundation’s Partnerships for International Research and Education (PIRE) Program is led by Lamont geophysicist Michael Steckler, in conjunction with Dhaka University. The international team also includes scientists from Vanderbilt University, the University of Minnesota and Queens College, and researchers in Germany, Italy, and India, as well as Lamont seismologists Won-Young Kim and Leonardo Seeber, as well as graduate students and postdoctoral scientists.

The project team has been upgrading a network of seismometers in Bangladesh that registers tiny tremors far below. This work 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 Himalaya. 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,” Lamont seismologist Leonardo Seeber said.

Seeber and Steckler, the project’s lead investigators, spend several weeks each year conducting fieldwork in Bangladesh. Seeber surveys surface geology in southeast Bangladesh, and in neighboring India, while Steckler monitors instruments that record natural sinkage and other movements of the surface. Steckler authors a blog from the field, describing the joys and challenges studying earthquakes, floods and sea-level rise in the Brahmaputra River delta.