Cooling Crusts Create Concomitant Cryovolcanic Cracks

The orbital and internal evolution of the ice-covered ocean worlds orbiting Jupiter Saturn are coupled, leading to time-varying thicknesses their ice shells. As thickens thins, thermal stresses in shell pressure underlying will change, promoting hindering fracturing shell. We identify when at what depth cracks initiate whether they can penetrate entire For an tensile strength 3 MPa, do not Europa. On Enceladus, time-averaged thickness less than 15 km variations tidal dissipation more 15% over approximately 100 Myr eccentricity cycles cause cross permit eruptions from ocean. Ocean overpressure is never large enough extrude water onto surface, suggesting that on Enceladus sustained by decompression boiling.