Hi Bob, As just a layman's opinion, it seems like one way to find evidence for a convective, mid-ocean spreading zone is to determine the age of the surface ice (youngest ice would be closest to the spreading zone). I would think the age of surface ice could be roughly estimated, since radiation sputtering would alter it's composition over long periods of time. Is this test not possible because the spreading zone might be moving relative to the surface? Could evidence be found to locate the subduction zones as well? Happy Easter! Tom == You are subscribed to the Europa Icepick mailing list: [EMAIL PROTECTED] Project information and list (un)subscribe info: http://klx.com/europa/
