...from the Nov. 22 "Geophysical Research Letters":
Buck, Leon; Chyba, Christopher F.; Goulet, Marc; Smith, Alex; Thomas, Paul Persistence of thin ice regions in Europa's ice crust 10.1029/2002GL016171 22 November 2002 Abstract Extensive data from planetary spacecraft as well as celestial mechanics models support the existence of a subsurface ocean on Europa ~100 km thick, maintained by a tidal heat flux. Models in which the overlying ice crust is less than 20 km thick permit breaches in the ice due to impact events or thermal plumes from the tidally heated core. We apply a two-dimensional thermal model to the analysis of the refreezing of a hole in the ice crust following a breach event. Our model incorporates heat produced by tidal heating of Europa in two ways: a basal heat flux from Europa's silicate and iron core, together with volumetric heating of the ice shell. We compare our refreezing timescales to those obtained from a model where viscous flow in the base of the ice crust fills the hole. We find that catastrophic breaches in Europa's ice crust may produce regions of relatively thin ice persisting up to ~1 My. These breaches are closed by viscous flow when radii are small (<10-50 km) and by conductive refreezing for larger radii, especially if Europa's crust has a high basal heat flow due to a hot core. Detection of the ice/ocean interface by orbital detection of the temperature anomalies or radar sounding would be most probable in the vicinity of these events. == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
