The repeated cycles of plate tectonics that have led to collision and assembly of large supercontinents and their breakup and formation of new ocean basins have produced continents that are collages of bits and pieces of other continents.
Water, salts and gases dissolved in the huge ocean that scientists believe could exist below Europa´s icy crust can rise to the surface generating the enigmatic geological formations associated to red-tinged materials that can be seen on this Jupiter's satellite.
Earth's crust was unstable in the Archean eon and dripped down into the mantle
Model calculations indicate that the extreme density of the base of the thickened primary crust caused it to subside into Earth's mantle.
A meteorite found in the Moroccan desert in 2011 appears to have originated in Mars' crust - and contains much more water than any Martian meteorite ever found before.
New images snapped by NASA's Lunar Reconnaissance Orbiter (LRO) indicate the moon's crust is actually being stretched - forming minute valleys in a few small areas on the lunar surface.
The Earth's wandering continents can't be fully explained by a layer of partially molten rock about 22 to 75 miles underground, NASA scientists say - something else must be contributing.
Geologists have embarked upon an ambitious project to drill through the earth's crust and extract a sample of the mantle.