The Igneous Rocks
At the beginning of the earth's history, its
crust was made up primarily of igneous
rocks.These rocks were formed from
lava which hardened as it cooled.
A great part of this lava solidified
before it reached the earth's surface.
It solidified beneath the surface, and
from this solidification the granite
rocks were formed.
The lava which solidified after it
reached the surface of the earth formed
basalt, volcanic rocks (rhyolite-basalt).
These rocks of volcanic origin do not
contain fossils, and they are not
formed in layers.
Pinegreenwoods Montessori
Montessori Geology
