types of rock
What are the three main types of rock?
Igneous, sedimentary, and metamorphic
What is melted rock called when it is inside the Earth?
magma
What is a fossil?
remains or imprint of a plant or animal from long ago
Which rock layers are usually the oldest?
bottom layers
What is weathering?
When rocks break into smaller pieces
Which rock forms from melted rock that cools?
igneos
What is magma called after it reaches the Earth’s surface?
lava
What do fossils tell us about the past?
What plants and animals lived long ago
Which rock layers are usually the youngest?
top layers
What is erosion?
When water or wind moves sediment
Which type of rock forms in layers?
sedimentary
What are small pieces of rock, sand, and shells called?
sediment
What is an example of a fossil?
A bone, shell, leaf imprint, or footprint
What happens when new layers form on top of old layers?
The old layers get buried
How do rivers help form sedimentary rock?
They move and drop sediment
Which rock forms because of heat and pressure?
metamorphic
What happens to sediment over time to make sedimentary rock?
It gets pressed together and hardens
Why do fossils take a long time to form?
Because layers build up slowly over many years
Why are fossils found in layers instead of alone?
Because layers build up over time
What must happen for a fossil to form?
The remains must be buried quickly
Which rock usually contains fossils?
sedimentary
Where does heat and pressure usually happen in the Earth?
Deep inside the Earth
Can all plants and animals become fossils?
No, only some do
How are rock layers like a history book?
Each layer tells a story from the past
Why is studying rocks and fossils important?
It helps us understand Earth’s history