Excitation of surface waves by the Aleutian underground explosion Milrow (October 2, 1969)

The average surface-wave and body-wave magnitudes of Milrow are determined to be Ms=4.94 and mb=6.47. Individual station magnitudes scatter by at least one unit about these averages. Milrow generated significantly smaller surface waves than earthquakes of comparable mb from the same geographical and tectonic region. These observations are consistent with those for the Aleutian underground explosion Longshot (October 29, 1965) and with similar Ms versus mb studies in other regions of the world that use data from a large number of seismograph stations covering a wide range of azimuth and epicentral distance.