# Dictionary:S-reflectivity

${\displaystyle R_{S}={\frac {\rho _{2}V_{S2}-\rho _{1}V_{S1}}{\rho _{2}V_{S2}+\rho _{1}V_{S1}}}}$
where ${\displaystyle R_{S}}$ is the normalized amplitude of an S-wave reflected from the interface between layers 1, 2, ${\displaystyle \rho _{1}}$, ${\displaystyle \rho _{2}}$ is the density of layers 1, 2, and VS1, VS2 is the S-wave velocity in layers 1, 2.