Hi! This is Valerie from the Plano Public Library.
Today, let's be Geologists and learn about the Earth.
Geology is the study of the Earth.
A geologist studies the materials that make up the Earth
like rocks and soil and what they look like
which are the physical characteristics.
And how they were made,
which is the processes that acted on them.
Let's study what happens when we take materials from the Earth,
like some dirt, rocks and sand,
and mix them with water.
Will they create a whole new material?
Or will all the rocks and soil stay separate?
What happened when we shook the jar?
When we combined the water with the materials from the Earth,
they formed a mixture.
A mixture doesn't combine to form a new substance
like when we bake a cake.
When we bake a cake, that is forming a chemical reaction
and something new is made.
Each ingredient in a mixture can be separated from the mixture.
What happened when we let the jar with the mixture
sit undisturbed?
Why did we see different layers?
As the mixture sat, the materials started to settle
out of the water and form layers of sediment.
The materials were different sizes
and masses, or weights.
The heavy items sunk to the bottom,
while the lighter items floated.
And some took just a little bit longer to settle out of the water.
This is called Sedimentation.
Sedimentation is the process of settling, or being deposited.
Rivers carry small and large particles.
The heavy things, like rocks, fall to the bottom first
while the smaller particles, like sand and dirt,
are carried farther in the water,
and eventually are deposited.
