A Historical and Geographical Analysis of Earthquake and Associated Tsunami Events on Bangladesh Coast

Bangladesh is vulnerable to a variety of natural hazards including frequent tropical cyclones and, less commonly, earthquakes and tsunamis. The 2004 Indian Ocean Tsunami (2004 IOT) challenged assumptions about the level of regional hazard. Remarkably, little historical data are available to help contribute to earthquake and tsunami risk reduction in Bangladesh. This research addresses this gap by documenting and analysing selected histories and geographies of earthquakes and associated tsunami events (i.e. 28 January 1679, 2 April 1762, 19 August 1868, 31 December 1881, 5 May 1930, 26 June 1941, 26 December 2004 and 11 August 2009) those originated in the northern Bay of Bengal and adjacent region. Findings indicate that only one definite tsunami, occurring in 1762, was generated in the northern Bay of Bengal. Analysis of earthquakes generated in the northern Bay of Bengal indicates that the 1762, 1881 and 1930 earthquakes caused widespread damage. A repeat of similar earthquakes from any of the active seismic sources could cause damage to major population centres in Bangladesh. However, these major earthquakes including 1679 event originating from the Bay of Bengal and adjacent regions did not generate large tsunamis in the northern Bay of Bengal.