This is an image of Europa showing what may be plates floating on a subsurface ocean.
Click on image for full size
NASA
Europa Tectonism
The surface of Europa was carefully examined for types of faulting and fracture. These provide evidence of the kind of stress (pushing and shoving) which the crust of Europa has undergone through time. The type of stress in turn provides evidence of the type of tectonism which characterizes Europa.
Examination of the surface of Europa shows evidence of icy-volcanism:
- smooth, unmodified plains
- lobate flow fronts
- flooded terrain (see lobate flow fronts)
- pyroclastic mantling
- plates (example shown here)
- strike/slip faulting (similar to that of the Earth's surface)
Examination of the surface also shows a relatively uniform cratering pattern remeniscent of that of Venus & Earth.
This style of icy-volcanism proves to be different from either that of Callisto or Ganymede. (The other major moon of Jupiter, Io has a more conventional form of volcanism.) The difference has to do with processes in the interior of Europa
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