Open AccessObservations of the phase SP at distances less than 40°
Author(s) -
Hendrajaya L.,
Muirhead K. J.,
Bock G.
Publication year - 1984
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1984.tb06486.x
Subject(s) - seismometer , mantle (geology) , geology , crust , seismology , shear (geology) , phase (matter) , geodesy , shear waves , geophysics , physics , paleontology , quantum mechanics
Summary. A detailed analysis of short‐period shear waves using an array of three component seismometers near Tennant Creek in the centre of northern Australia has found only isolated samples of the phase Sp which, for a mode conversion at the crust/mantle boundary precedes the S arrival by about 6 s. Two strong phases commonly observed in the S wavetrain in the distance range 30–40° with a time separation of between 6 and 8 s have been determined to be the phases S and SP respectively. Contrary to the Jeffreys‐Bullen seismological tables, SP is first generated at a minimum distance not of 40°, but rather in the vicinity of 20°.