Propagation of Lg waves across eastern Europe and Asia. [Lg waves are surface shear waves initiated by seismic activities and propagated through the earth's crust]

We have assembled and discussed a large body of information published between 1954 and 1977 available to us regarding Lg propagation across Asia and eastern Europe. The data from earthquakes located within the boundaries of the U.S.S.R. indicate that both short- and long-period Lg waves propagate efficiently across most of the Soviet Union land mass. The data from certain border regions, however, display erratic characteristics that may be due to propagation, source depth, or radiation pattern. These regions include paths across southern portions of the Black and Caspian Seas, the Caucasus Mountains, the Uzbek and Tadzhik Republics, the Sea of Okhotsk, and the northern seas (e.g., the Kara Sea). The only areas that appear to block Lg propagation completely are the central portions of the Sea of Japan and regions of the People's Republic of China.