Europa: Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting

Europa. We show that tidal energy can be preferentially focused in rising plumes for viscosities in agreement with laboratory experiments. When the plume cores reach the base of the outer cold brittle layer, they spread laterally, causing shallow melting, disruption, and formation of terrain similar to lenticulae and chaos. We show that this mechanism can readily explain the major characteristics of chaos and lenticulae even if the average outer solid ice layer thickness is larger than 20 km.

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