Minerals
This tool helps scientists figure out what mineral they have by testing hardness.
Moh’s Hardness Scale
Rocks are grouped based on this
How they form
This is molten rock that comes out of a volcano
lava
There are these two main types of weathering
physical and chemical weathering
This top layer of soil is full of organic matter and humus
The O Horizon
This word describes how shiny a mineral is
luster
These rocks form from melted rock deep inside the Earth or from lava
Igneous Rocks
Igneous rock that forms under the Earth cools at this speed
slowly
In this process, freezing water expands in cracks and breaks rocks apart
Ice-wedging
This layer is made of large broken rocks and is called parent material.
The C Horizon
A rock is made of more than one of these natural ingredients
minerals
Marble, slate, and quartzite belong to this group
metamorphic rocks
This is molten rock beneath Earth’s surface
magma
This type of physical weathering happens when rocks rub against each other.
abrasion
This solid layer of rock is found at the very bottom.
Bedrock
This glowing orange-brown change happens when minerals react with oxygen
oxidation (rust)
This type of rock forms from compacted sediment, minerals left by water, or fossils
sedimentary rock
Igneous rock that forms on Earth’s surface cools at this speed
quickly
Plant roots widen cracks in rocks in this type of weathering
Plant action
This layer is also known as topsoil.
The A Horizon
What are some minerals that can be found in Arizona?
One of these responses is a correct answer: Amethyst, Garnet, Peridot, Onyx, and Turquoise
These igneous rocks cool quickly on the Earth’s surface—obsidian and pumice are examples.
extrusive igneous rocks
Granite and diorite form when magma cools slowly underground. What kind of igneous rocks are these?
Intrusive igneous rocks
Acid rain melting a statue is an example of this
chemical weathering (dissolving by acid)
This layer is called subsoil.
The B Horizon