ON NOVEMBER 21, 2025, at 10:38 am, a 5.5–5.7 magnitude earthquake, with its epicenter in Madhabdi, Narsingdi, 13 kilometres from the Agargaon Meteorological Centre in Dhaka, shook the ground in central Bangladesh, including the Dhaka metropolis. The source (or focus) of this earthquake was approximately 10 kilometres below the surface, and the tremor was strong enough to be felt in Kolkata. The death toll from this moderate quake remained 10, though more than five hundred were injured. While the damage was less severe than that caused by other natural disasters in Bangladesh, the event serves as a sobering wake-up call.
Beneath Bangladesh lies a complex and precarious chessboard of tectonic settings, where fractured pieces of the Earth’s crust interact by sliding, dropping, overriding and thrusting in ways that could place thousands of lives at risk. This fracture in the rock, along which relative movement occurs, is known as a fault.
Bangladesh’s tectonic vulnerability stems from its position at the collision zone of the Indian plate and the Eurasian plate, with the Indian plate’s eastern edge sliding beneath the smaller Burma plate. This process forms the Indo-Burma Subduction Zone, where immense compressive stress accumulates over thousands of years. From this dangerous setting emerge several fault systems capable of inflicting tremendous harm.
Among them, the east-west-trending Dauki fault, a reverse fault under compressive stress, cuts across northern Bangladesh, with Sylhet lying next to it. Another major fault, the Madhupur Fault, trends northwest–southeast and approaches Dhaka itself. Along the eastern border, from Tripura to Chittagong and extending to the Andaman Islands, north–south-trending faults remain active within the Indo-Burma Subduction Zone, placing Chittagong directly on this perilous system. These faults are capable of producing earthquakes of magnitude seven or higher. History offers a chilling reminder: in 1897, the Dauki Fault unleashed a quake exceeding magnitude 8.
By contrast, the Narsingdi earthquake was far smaller in scale, yet its cause was no less significant. It occurred on the Indian Plate due to a sudden rupture and reverse slip along the southeastern segment of the Madhupur Fault, possibly triggered by stress release at the Indo-Burma Subduction zone. Still, detailed seismic research has yet to confirm these conjectures advanced by geologists in Bangladesh.
Scientific explanations, however, only tell part of the story. The tragedy of Narsingdi lies in the human toll of unpreparedness. Lives were lost in Old Dhaka when walls and railings collapsed. Students at Dhaka University jumped from buildings in panic, suffering broken limbs. In Gazipur, a stampede in the garment industry left hundreds injured. Power plants across five districts, including Chittagong, were forced to shut down. These events raise a painful question: are we truly prepared to face such disasters?
The answer points to several glaring weaknesses: aging and improperly constructed buildings, panic-driven behaviour, lack of public awareness and systemic unpreparedness. Addressing these requires decisive action, strict enforcement of building codes, retrofitting unsafe structures and mandatory earthquake safety drills in schools, homes and offices. Vital infrastructure such as hospitals, power plants, water and sewerage systems and bridges must be strengthened to withstand future shocks.
Yet preparedness is not only about physical structures; it is also about combating misinformation. Since the Narsingdi earthquake, rumours and doomsday scenarios have spread unchecked. To counter fear, we must return to science and understand the physics of earthquakes through thought experiments.
An earthquake occurs when a sudden rupture on a fault plane releases energy accumulated over centuries or even eons by the relative movement of rock blocks. In Narsingdi, the rupture was intraplate. Energy propagated outward as seismic waves — P, S and surface waves — traveling at different speeds. P waves are fastest, surface waves slowest, but it is the latter that cause the most destruction. To grasp the impact, consider Mohsin Hall at Dhaka University, where students panicked and leapt from upper floors during the quake.
Had the quake been of magnitude 6.5 instead of 5.5, Mohsin Hall would have swayed with 10 times the amplitude and endured about thirty-two times the energy. The Richter Scale is logarithmic, meaning each increase in magnitude multiplies the destructive force. The Narsingdi quake released energy equivalent to one-sixth of the Hiroshima bomb. A 6.5 magnitude quake would equal five to six atomic bombs.
At magnitude 7.5, the consequences would be apocalyptic. Mohsin Hall would sway with a hundred times the amplitude, and the energy release would be 1024 times greater, equivalent to 25 to 36 Hiroshima-type bombs. Dhaka would face near annihilation: buildings reduced to rubble, electric lines sparking infernos, rescue efforts paralysed, communications severed and a dystopian darkness pierced only by flames.
This leads to a daunting question: could such a quake strike near Dhaka, at a depth of 10 kilometers, as in Madhabdi? The horrific answer is yes, it could. Seismologists warn that the Madhupur Fault is capable of generating quakes of magnitude seven or higher and it runs perilously close, from northern Tangail through Narsingdi to Gulshan-Badda. Prediction, however, remains elusive. Even in the USA and Japan, the most advanced in seismic science, earthquakes cannot be forecast with precision. They may occur tomorrow, centuries later, or never. At best, institutions like the USGS can monitor fault systems, calculate stress fields, and estimate probabilities over decades, but timing, magnitude and location remain beyond reach.
Earthquakes are natural phenomena born of tectonic interactions, beyond human control. What we can control is our preparedness. The Narsingdi earthquake is not merely an isolated tremor, it is a wake-up call. Bangladesh must heed it, for the stakes are nothing less than survival.
Dr Mostofa Sarwar is professor emeritus of geophysics at the University of New Orleans. He was a director on the board of the International Research Institute of Seismology.
