Answer:
Explanation:Igneous rocks
are formed
when rock is
super-heated and
becomes molten
(liquid). There are two kinds of
molten rock: magma (found
beneath the Earth’s surface) and
lava (found on the Earth’s
surface). The molten rock cools
and hardens on or beneath the
Earth’s surface forming a variety
of igneous rock. Two examples
are granite and basalt.
Layers in Time: Geology of Grand Canyon
How did Grand Canyon form? By studying geology we
learn about the Earth’s history and how places change over time.
What plants or animals lived in your town 150 million years ago?
The ancient remains of plants and animals preserved in the rock,
called fossils, tell stories about the past. Take a look at the chart of
common fossils at Grand Canyon on the back page.
Vocabulary:
Fossils: the hardened
remains or imprints of plants
or animals preserved in rock
Geology: the study of the
origin, history and structure
of the earth
THE OLDEST PANCAKE IN A
STACK IS ALWAYS AT THE
BOTTOM. THE ROCKS AT
GRAND CANYON ARE A LOT
LIKE PANCAKES. WHERE
DO YOU FIND THE OLDEST
ROCKS AT GRAND CANYON?
Think About It
Sedimentary rocks are made
of smaller pieces (like sand or
mud), called sediments, that
pile into layers. As pressure
on the sediment increases over
time, minerals act like glue,
cementing them into solid
rock. The three main types of
sedimentary rocks at
Grand Canyon
are sandstone,
shale (or
mudstone),
and limestone.
Metamorphic rocks are
rocks that
have been
changed
under
great heat
and pressure. The original
rock can be sedimentary,
igneous, or even metamorphic.
The original rock is changed
into something new, just as a
caterpillar “metamorphoses”
into a butterfly
