A Physics-Based Frequency-Temperature Seismic Anelastic Attenuation Model for Planetary Ice Shells

Abstract

Intrinsic attenuation in planetary ices remains poorly constrained at seismic frequencies and low temperatures, limiting quantitative predictions of wave propagation in icy moons. Existing models typically rely on constant-Q, or power-law formulations that lack microphysical grounding and fail to capture the strong temperature sensitivity of ice Ih. Here, we develop a physics-based attenuation model that combines dislocation relaxation, grain-boundary sliding, and proton reorientation mechanisms within a unified Cole-SAS-Maxwell framework, providing a consistent transition between seismic and tidal frequency regimes. The model is calibrated against laboratory and semi-empirical constraints over a broad range of homologous temperatures (0.34–1  $T_m$ for ice Ih; 94 K–273 K in absolute temperature) and pressures up to 100 MPa. The proposed framework predicts order-of-magnitude variations in intrinsic shear attenuation across icy-shell thermal profiles and provides a quantitative framework for assessing wave dispersion, energy loss, and seismic detectability in the shells of Titan-like satellites.