Exploratour - Does Europa have an Ocean?
3.) The picture seems to show the presence of a "puddle" which has seemingly wiped out the linea or raised ridges nearby. Since scientists cannot prove that this feature is really the remnants of a puddle, they call the feature "lobate flow" to describe the rounded lobes or smooth curves which the feature has. Such a patch probably involves a local pocket of water and suggests the process which geologists call "cryovolcanism" or icy-volcanism (cryo means cold). In this case, a volcanic cone is not formed, but a liquid comes out of the ground and flows on the surface.
You may leave the tour and read more about terrestrial volcanism and how volcanic cones are formed on Earth using the link at the bottom of the page.
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