A remain or trace of an organism preserved in a rock
What is a fossil?
100
These rocks can get compacted and semented together
What is sedimentary, igneous, and metamorphic rocks?
100
Earth was made around this time
What is 4.5 billion years?
100
The beginning a timeline
What is today?
100
These are the three types of rocks
What is Igneous, metamorphic, and sedimentary rocks?
200
remains or traces of organisms that have lived for a short time and are all around the world
What are index fossils?
200
These rocks can turn into molten lava and then cools and hardens
What is igneous, sedimentary, and metamorphic rocks?
200
The first human was made around this time
What is 200,000 years?
200
The longest era
What is Precambrian time?
200
A material a rock contains when it fizzes
What is calcite?
300
A rock that is most likely to contain a fossil
What is a sedimentary rock?
300
These rocks can can change due to heat and/or pressure
What is igneous, sedimentary, and metamorphic rocks?
300
The first dinosaur was made around this time
What is 245 million years ago?
300
The type of time scale that shows exactly when something happened.
What is a numeric time scale?
300
sand being carried by a river
What is transport?
400
Because they tell us about the organisms that lived on Earth from the time of the oldest fossils, about 3.8 billion years ago, to the present.
Why are fossils useful to scientists?
400
The material that glues the sand together to create sandstone
What is matrix?
400
70-75% of all species went extinct in the Triassic-Jurassic transition.
What is the great extinction?
400
A type of timescale that shows a proportional time it happened
What is a proportional time scale?
400
A representation of something that's difficult to observe directly
What is a model?
500
A process based on radioactive decay of elements to determine a minerals age
What is radioactive dating?
500
Particles that settle when whatever is carrying them slows down.
What is a sediment?
500
Trilobites appeared around this time.
What is 570 to 505 million years ago?
500
it was about 4.5 meters across
how long was the class time line?
500
A series of process that cause rocks to change. This cycle has been going on since earth formed. It is still happening today, and it will continue as long as earth exists.