Lithosphere for silicate rocks, and formula_4 is the age of the given part of the lithosphere. The age is often equal to L/V, where L is the distance from the spreading centre of mid-oceanic ridge, and V is velocity of the lithospheric plate. Oceanic lithosphere is less dense than asthenosphere for a few tens of millions of years but after this becomes increasingly denser than asthenosphere. This is because the chemically differentiated oceanic crust is lighter than asthenosphere, but thermal contraction of the mantle lithosphere makes it more dense than the asthenosphere. The gravitational instability of mature oceanic lithosphere has the
The Word for World Is Forest Word for World Is Forest" portrays a communication gap that the protagonists are never able to bridge. Both the native Athsheans and the loggers have languages that reflect their perceptions of reality, but they are unable to find a common language. In the native Athshean language, the word ""Athshe"" means both "forest" and "world", demonstrating the close link that the Athsheans have to the forest and their planet. It is noted by Lyubov that the Athsheans believe "the substance of their world was not earth, but forest". The language used by the Athsheans during conversations similarly show their interconnectedness and