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 Litany of Earth The Litany of Earth The Litany of Earth is a 2014 fantasy/horror fiction novella by Ruthanna Emrys, revisiting H.P. Lovecraft's story "The Shadow Over Innsmouth". It was first published on Tor.com. Decades after the residents of Innsmouth were forced into internment camps by the United States government, Aphra Marsh discovers humans trying to replicate her people's secret mystical rituals. "Litany of Earth" was included on "Locus Magazine"s recommended reading list for 2014. Charlie Jane Anders stated that the story was "something special". An analysis by Io9 indicated that, if not for the involvement of the Sad Puppies, "Litany of Earth"