Open AccessComment [on “Possible forms of seismic anisotropy of the uppermost mantle under oceans” by George E. Backus]
Author(s) -
Crampin Stuart
Publication year - 1982
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/jb087ib06p04636
Subject(s) - anisotropy , wave equation , geology , geophysics , mantle (geology) , shear (geology) , seismic wave , shear waves , seismic anisotropy , s wave , physics , optics , petrology , quantum mechanics
Over 15 years ago, Backus (1965) demonstrated approximate equations for the velocity variations of body waves in weakly anisotropic solids. The P wave equation is widely quoted (Aki and Richards (1980) and many others) as modeling P wave variations over all planes in all anisotropic solids. As there appears to be revival of interest in anisotropy, it is worthwhile to note a minor limitation to the application of the P wave equation and to draw attention to some similar linear equations for shear waves, which combined with the P wave equation are very successful in modeling the velocity variations of anisotropic solids.