This image of Europa shows dark scalloped features that seem to have started in the center of the features and spread apart.
Click on image for full size
Image courtesy of NASA
Possible Spreading Centers on Europa
The surface of Europa shows many signs of that there may be a submerged ocean. For example, in this picture there are several dark bands that look like they could be joined at each edge. This may be a geologic feature that resembles what on Earth are called
spreading ridges.
Other signs of the potential for a submerged ocean include:
*
flooded terrain
*
'freckles'
*
rafting, and
*
'mushy' craters.
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