These equations relate the amplitudes of P-waves and S-waves at each side of an interface, between two arbitrary elastic media, as a function of the angle of incidence and are largely used in reflection seismology for determining structure and properties of the subsurface.

The only place in Germany where Zoeppritz could specifically study geophysics was at the University of Göttingen, as an assistant in the influential Emil Wiechert's research group.

[2] These curves were later used by other members of the research group, Ludwig Carl Geiger and Beno Gutenberg,[3] as well as the British astronomer and seismologist Herbert Hall Turner at the International Seismological Summary.

[4] The related ill-posed inverse problem of inferring a discrete velocity distribution, representing the layers of the crust and mantle, was solved by fellow Göttingen mathematician Gustav Herglotz.

[5] Zoeppritz used Wiechert's work and went on to derive a full set of transmission and reflection coefficients for a plane wave approaching a discontinuity.