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
For the Beauty of the Earth For the Beauty of the Earth "For the Beauty of the Earth" is a Christian hymn by Folliott S. Pierpoint (1835-1917). Pierpoint was 29 at the time he wrote this hymn; he was mesmerized by the beauty of the countryside that surrounded him. It first appeared in 1864 in a book of Eucharistic Hymns and Poems entitled "Lyra Eucharistica, Hymns and Verses on The Holy Communion, Ancient and Modern, with other Poems." It was written as a Eucharistic hymn - hence the title of "The Sacrifice of Praise", the refrain "Christ, our God, to Thee we raise, This, our sacrifice