Using Tidally-Driven Elastic Strains to Infer Regional Variations in Crustal Thickness at Enceladus

Constraining the spatial variability of the thickness of the ice shell of Enceladus (i.e., the crust) is central to our understanding of the internal dynamics and evolution of this small Saturnian moon. In this study, we develop a new methodology to infer regional variations in crustal thickness using measurements of tidally-driven elastic strain that could be made in the future. As proof of concept, we recover thickness variations from synthetic finite-element crustal models subjected to diurnal eccentricity tides. We demonstrate recovery of crustal thickness to within similar to 2 km of true values across the crust with similar to 10% error in derived spherical harmonic coefficients at degrees l <= 12. Our computed uncertainty is significantly smaller than the inherent similar to 10 km ambiguity associated with crustal thickness derived solely from gravity and topography measurements. Therefore, future measurements of elastic strain can provide a robust approach to probe crustal structure at Enceladus.