An earthquake with exceptionally strong higher-mode surface waves
- 27 Downloads
An earthquake in the Northern Sinkiang Province, China, on November 13th, 1965, produced exceptionally strong higher-mode surface waves recorded at the Swedish seismograph stations, especially by the Galitzin seismographs at Kiruna. Group-velocity dispersion curves are deduced for the second Rayleigh and the second and third Love wave modes. The energy content of the second Rayleigh and Love modes is computed, and it is found that the former amounts to about 70 times as much as in average. Various reasons for this exceptional behaviour are discussed, such as depth extent of focus, focal mechanism and properties of propagation path.
KeywordsSurface Wave Dispersion Curve Energy Content Focal Mechanism Propagation Path
Unable to display preview. Download preview PDF.
- D. Anderson andM. N. Toksöz,Surface waves on a spherical earth. 1. Upper mantle structure from Love waves, J. Geophys. Res.68, 11 (1963), 3483.Google Scholar
- M. Båth,The elastic waves Lg and Rg along Euroasiatic paths, Arkiv f. Geofys.2, 13 (1954), 295.Google Scholar
- M. Båth,The relation between magnitude and energy of earthquakes, Trans. Amer. Geophys. Un.36, 5 (1955), 861.Google Scholar
- M. Båth,The energies of seismic body waves and surface waves, Contr. in Geophys. (Gutenberg Vol.)1 (1958), 1.Google Scholar
- M. Båth,Earthquake energy and magnitude, Phys. and Chem. of the Earth7 (1966), 115.Google Scholar
- M. Båth,Propagation of Sn and Pn to teleseismic distances, Pure and Appl. Geophys.64,2 (1966), 159.Google Scholar
- S. Crampin,Higher modes of seismic surface waves: Preliminary observations, Geophys. J.9, 1 (1964), 37.Google Scholar
- S. Crampin,Higher modes of seismic surface waves: Second Rayleigh mode energy, J. Geophys. Res.70, 20 (1965), 5135.Google Scholar
- S. Crampin,Higher modes of seismic surface waves: Propagation in Eurasia, Bull. Seism. Soc. Amer.56, 6 (1966), 1227.Google Scholar
- S. Crampin andM. Båth,Higher modes of seismic surface waves: Mode separation, Geophys. J.10, 1 (1965), 81.Google Scholar
- R. L. Kovach andD. L. Anderson,Higher mode surface waves and their bearing on the structure of the earth's mantle, Bull. Seism. Soc. Amer.54, 1 (1964), 161.Google Scholar