Source parameters of the siberian explosion of June 30, 1908, from analysis and synthesis of seismic signals at four stations
Ari Ben Menahem, Adolpho Bloch
Geophysical Observatory, Department of Applied Mathematics, The Weizmann Institute of Science, Rehovot, Israel
Received 16 May 1975; accepted 13 June 1975.
Available online 28 October 2002.
Abstract
Old seismograms of the Tungus event of June 30, 1908, are analysed and compared with contemporary records of air explosions from Novaya Zemlya and Lop-Nor. Observed arrival times and absolute amplitudes of Rayleigh waves, infrasonic-coupled ground-motion and SH crustal shear waves at Jena, Tiflis, Tashkent and Irkutsk, support a source model which consists of a combined action of an atmospheric-explosion equivalent to a vertical point impulse of magnitude 7 · 1018 dyn sec and a ballistic-wave equivalent to a horizontal point impulse of magnitude 1.4 · 1018 dyn sec striking S65°E toward the northwest.
All the accumulated knowledge in earthquake and explosion seismology since the beginning of the century is harnessed to the effort of interpreting the observed seismograms. The agreement between the observations in the epicentral area and the ensuing signals in the far seismic and acoustic field support the hypothesis that the Siberian UFO explosion had the effects of an Extraterrestrial Nuclear Missile of yield 12.5 ± 2.5 Mt.