Attenuation relationships for intensities in Bangladesh have been studied from published isoseismal information of seven regional earthquakes with magnitudes varying from 5.1 to 8.1. Attenuation of earthquake intensity appear to have directional dependence, and directions affecting Bangladesh appear to show greater attenuation. Attenuation equations for intensity have been developed for two cases: (i) Model-1, using epicentral distance and (ii) Model-2 using hypocentral distance. The developed models agree quite well with field data for the different earthquakes except for the Srimangal earthquake which was a shallow earthquake with relatively faster attenuation. Finally, attenuation laws for PGA have been obtained for both models and it is found that Murphy and O’Brien (1977) intensity PGA relationship yields PGA based attenuation laws for Bangladesh that are also close to some standard attenuation law.
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