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BlockbusterThe Earthquake Scenario in Bangladesh

As Bangladesh is located in a tectonically active much of the country including Chittagong, Sylhet, Dhaka, Rangpur, Bogra, Mymenshing, Comilla, Rajshahi are very much vulnerable to major earthquake disaster. Although, some awareness is raised among a limited groups, due to some recent earthquakes in the region, practically the country is far behind the minimum preparedness level to face such a disaster in any of our cities.

Significant damaging historical earthquakes have occurred in and around Bangladesh, and damaging moderate-magnitude earthquake occur every few years. The country’s position adjacent to the very active Himalayan front and ongoing deformation in nearby parts of south-east Asia expose it to strong shaking from a variety of earthquake sources that can produce tremors of magnitude 8 or greater. The potential for magnitude 8 or greater earthquakes on the nearby Himalayan front if very high, and the effects of strong shaking from such an earthquake directly effect much of the country. In addition, historical seismicity within Bangladesh indicates that potential for damaging moderate to strong earthquakes exist throughout much of the country. Large earthquakes occur less frequently than serious floods, but they can effect much larger areas and can have long-lasting economic, social, and political effects.

Liquefaction is another source of earthquake related damage. During sustained strong shaking, poorly consolidated, water saturated sediments can liquefy and loose their ability to support loads. The foundations and supports of structures built on liquefiable sediments can fail, causing damage or destruction. Much of the country is of loose sandy soil and most of it remains in saturated condition round the year, thereby vulnerable to liquefaction in case of sustained ground motions.

Based on the above discussions, the probable scenario for an earthquake to a scale of M6.5 or above in...