A note on surface waves from the Hardhat nuclear explosion

The records from many LRSM stations have been studied in order to determine the nature and origin of the Love and Rayleigh waves that were generated by the Hardhat explosion. A check was first made on the validity of the assumption that Love and Rayleigh waves originated from a common source at the same time. The origin times of the two waves were shown to agree within the experimental error, and the assumption was not rejected. The amplitude ratio and the source phase difference between the two waves were obtained for various azimuths from the source, and they were shown to be consistent with the double couple corresponding to a vertical strike-slip fault, the strike direction being N30°W or N60°E. The observation, however, permits a superposition of an explosive source, making the contribution to the amplitude of Rayleigh waves less than half of that from the double couple.