G ginscpy Senior Member Sep 10, 2010 7,950 232 48 Mar 14, 2011 #1 higher magnitude than the Japan quake. Worlds largest nuclear test by the Soviet Union (a 50megaton big-one/above ground in the atmosphere)) - about an 8.0 Below Karakatoa above Mt St Helens, 1906 SF quake. Hiroshima bomb about a 6.2
higher magnitude than the Japan quake. Worlds largest nuclear test by the Soviet Union (a 50megaton big-one/above ground in the atmosphere)) - about an 8.0 Below Karakatoa above Mt St Helens, 1906 SF quake. Hiroshima bomb about a 6.2