Numerical simulations of solid-state convection within Ganymede's ice
shell in a 2-dimensional cylindrical geometry
Abstract
Solid state convection is expected to influence the evolution and the
geological activity of Ganymede [1]. The spatial distribution of
tidal dissipation could influence the temperature structure of the outer
ice shell and, likely, the internal processes and the geological
activity. We investigate the influence of the tidal dissipation on a
convective ice shell of Ganymede. We use the finite-element code ASPECT
[2] to solve the Boussinesq fluid equations of the conservation of
continuity, momentum and energy to simulate solid-state convection
within the ice shell of Ganymede. The numerical simulations are
performed in a 2-dimensional cylindrical geometry. We adopt a
temperature-dependent Newtonian viscosity for the water ice, assuming
diffusion creep. The spatial distribution of the tidal dissipation rate
is computed adopting a Maxwellian material model [3, 4]. Preliminary
results show how the convective patterns, and the thermal plumes are
influenced by the spatial distribution of the tidal dissipation. We also
discuss how radar sounder investigations with RIME instrument [5] on
board of the ESA’s JUICE mission in combination with radio science
measurements of the gravity field by 3GM experiment [6] could
characterize the thermal structure of Ganymede’s ice shell.