An attempt is made to extend the application of the weak-attenuation concept to the computation of reflection and transmission coefficients at interfaces separating weakly attenautive media. Specifically, effects of weak attenuation on SH-wave reflection and transmission coefficients at interfaces separating weakly attenuative isotropic media are studied. The study is based on the assumption of validity of the correspondence principle; fixed frequency is considered. Basic role in the evaluation of coefficients is played by slowness vectors of incident and transmitted waves. They have to satisfy corresponding approximate eikonal equations and the Snell law. Resulting formulae for coefficients are singular for the angle corresponding to the critical incidence in the reference elastic medium. Outside the vicinity of this angle, results of the proposed formulae approximate well results of the reference formulae for attenuative media. The width of the vicinity depends on the magnitude of the quality factors on both sides of the interface, and more strongly on the inhomogeneity of the incident wave.
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