billion six hundred million years ago the Earth
is born from a cloud of dust and fire orbiting the
sun. In the beginning there are no seas upon the
barren Earth. The sun blisters down as poisonous
gases swirl about. Racked with volcanoes, bombarded
by asteroids and comets, Earth is incredibly hot
with a sea of molten rock covering its surface.
The early Earth is a world in slow turmoil for many,
many thousands of years.
Over time the Earth cools and separates into several
different layers. The matter with the highest
density (mostly iron) sinks to form Earths
solid inner core. This inner core becomes enveloped
by a less dense mixture of nickel and iron - the
outer core. Surrounding the inner and outer core
is the mantle (itself divided into several distinct
layers), and over the mantle is the Earths
crust, a thin veneer of rocky material that covers
the planet like the cracked, twisted, lumpy crust
of an apple pie.