Thermal Convection in Europa’s Silicate Mantle

We perform numerical simulations in 3D spherical geometry to study the properties of convection in Europa’s silicate mantle using the finite-element code CitcomS including temperature-dependent viscosity. Our simulations show that thermal convection occurs if the reference viscosity is – PaS, rheological activation energy is 150-300 kJ/mol, and the viscosity contrast (due to temperature variation) is less than in Europa’s mantle. Convection cannot occur if the reference viscosity PaS or if the viscosity contrast . These results imply that partial melting may be required for thermal convection to occur in Europa’s silicate mantle.