This brings us
to Mercury and the Pre-cambrian Earth and the full sequence of an
Earth’s life-cycle as outlined in ‘The Visible Earths’.
See 'Mercury' and 'Full
By the time the ecosphere is sufficiently
clear so that the development of Earths is not threatened, the disk
of gas and dust swirling around the star has been reduced to an
outer-lying belt of more rubble-like debris. I believe this belt
can be seen in this solar system in the form of the asteroid belt
that lies mostly between Mars and Jupiter.
For the rest of this sequence see the ‘Asteroids’
section in ‘The Visible Earths’. ( this is where accretion
is applied in this model, as the main process in the transformation
from rock planet to gas giant, rather than as the primary source
of generating the core and rock sphere in the beginning )