Fossil Types
Dating Rocks
Events in Geologic Time
Minerals
Rock Types
100
The preserved remains or traces of an organism.
What is a fossil.
100
The age of a rock compared to other rocks.
What is relative age.
100
An event in which many types of living things become extinct at the same time.
What is a mass extinction.
100

This is the least reliable characteristic when classifying minerals and why.

Color because many minerals share the same colors or vary in color

100

The way in which we classify different types of rocks. 

What is the way in which they are formed.

200
A hollow imprint that shows the shape of an organism.
What is a mold.
200
Useful fossils that help to tell the relative ages of the rocks around them.
What are index fossils.
200
This is an example of a geologic time marker.

Volcanic Eruption, Crater from asteroid.

200

This is the mineral property in which pieces break off in sheets or rectangular pieces.

Cleavage

200
This is the type of rock formed from this process where only heat is required to form the rock. (GIVE BOTH ANSWERS)

Metamorphic rock from contact metamorphism

300

An example of this type of fossil would be footprints.

HINT: "these organisms are gone without a ______"

What is a trace fossil.

300
An intrusion in always _________ than the rocks around it.
What is younger.
300
The subdivisions of eras are called ______________ .
What is periods.
300

This is the mineral property in which a colored powder is left behind after being dragged across a surface.

Streak

300

What is the relationship between cooling time and crystal size for igneous rocks? 

Longer the cooling time, the larger the crystals

400
A fossil formed when minerals replace all or part of an organism.
What is a petfrified fossil.
400
The method used to determine the absolute age of rocks.
What is radioactive dating.
400

What do most scientists think caused the mass extinction at the end of the Cretaceous Period (think Jurassic)?

What is an object from space struck Earth.

400

Why do certain rocks bubble when they are combined with HCl?

because minerals such as calcite are in them which have those properties

400
What law in relative dating is most useful in explaining the age of sedimentary rocks and why?

Law of Superposition because the layers form horizontally

500
The state fossil of New York.
What is a trilobite.
500
Explain how the Law of Superposition is used to determine the relative ages of sedimentary rock layers.
What is the oldest layer is that the bottom, and each higher layer is younger than the rocks below it.
500

Earth's atmosphere, oceans, and continents began to form during the first several hundred millions years of this eon.

What is Precambrian Time.

500

Minerals known as silicates contain which two elements?

Silicon and Oxygen

500

How would you describe the texture of a rock that  formed with gas pockets? Where do these rocks form?


Extrusive and vesicular