makeup of the eart, lesson 3
TRANSCRIPT
What Materials Make Up the
Earth’s Surface?
Diamonds, rubies, and gold! These are minerals that come from the earth.
Imagine—There are places on earth where people can dig up gems and metal!
Nonliving, solid matter from the earth.
Minerals
Luster: The way a mineral reflects light.
Minerals that reflect a lot of light are shiny.
Gold is an example of a mineral that reflects a lot of light.
Properties of Minerals
Color
Minerals come in many different colors. Some minerals are found in several colors, and
some may even change color. Some minerals are used to make gemstones.
Properties of Minerals
Hardness
If you want to know how hard a mineral is, rub it against another mineral. The harder mineral will scratch the softer mineral.
The hardness of a mineral helps to identify the mineral
Diamonds are the hardest mineral
Properties of Minerals
Rocks are not all alike! Some form deep inside the earth. Others form at the bottom of lakes and
oceans.
Rocks
Some igneous rocks are made from magma
that cools below the earth’s surface. Granite is an igneous rock.
Igneous Rock
Are made of tiny pieces of other rocks, shells,
and other materials. Formed in the bottom of the water by the
pressure of the water. Sandstone is an example of sedimentary rock.
Sedimentary Rock
Rocks that are deep inside the earth and
change into different kinds of rocks. Heat and pressure change the rocks over
many years. Limestone (a sedimentary rock) can be
changed into marble.
Metamorphic Rock
Is formed from years of weathering of rocks
and minerals and the decaying of dead plants and animals.
Contains air and water. Used by plants and animals for nutrients.
Soil
Sand
Loose and has large grains Does not hold water well Soil with too much sand is not best for growing
crops
Types of Soil
Clay
Smooth and has fine, tightly packed grains Water does not soak into clay quickly Clay can hold a lot of water Rich in nutrients Plants do not grow well in clay because it is too
hard for roots to grow in
Types of Soil
Topsoil
Dark soil Rich in nutrients Holds water well Plants grow well in topsoil
Types of Soil