Infrasound monitoring and yield estimation of Massive Ordnance Air Blast (MOAB): A case study of 2017 Afghanistan air strikes

On April 13, 2017, at 1502 GMT, the United States used a thermobaric weapon, deploying the Massive Ordnance Air Blast against Islamic State of Iraq and Syria hideouts in the Achin district of Afghanistan. This event provided a unique opportunity to study the infrasonic signals generated by the explosion. A distinct infrasound signal was captured by a seismo-acoustic station located in Pakistan, approximately 249 km from the detonation site. This study presents an analysis of the recorded infrasonic signal and an estimation of the explosive yield using seismo-acoustic methodologies. The recorded signal exhibited significant atmospheric coupling, with an average pressure amplitude measured at 0.1717 pascals. The explosive yield, estimated after accounting for atmospheric corrections, was found to be approximately equivalent to 14 tons of trinitrotoluene. The findings enhance the understanding of infrasonic monitoring for explosive events and provide critical insights into the atmospheric coupling of such signals. These results have broader implications for the assessment of environmental impacts and the development of monitoring techniques for large-scale detonations.