Seismic measurements of large underwater shots

A series of 10,000-pound high-explosive shots was fired at various water depths off San Clemente Island, California during August 1961. These shots were recorded on magnetic tape at one fixed station (123 km) and at portable stations located at 180, 196, 500, and 518 km. The effect of water depth on the amplitude and spectra of the seismic waves generated by these shots is discussed, and a comparison is made with the maximum displacement of underground shots. A spectral comparison is also made with a local earthquake recorded at two of the shot recording sites.