Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account

Vocabulary terms for Unit assessment


The hollow space that is left after an organism's remains dissolve.

absolute age

The age of a rock in years.

index fossil

A fossil that lived in many places around the world for a short period of time; it can help scientists find the age of a rock layer that may be out of order.


Scientists who study fossils and compare them to living things today.

trace fossils

A type of fossil formed when an animal's footprint hardens in sediment.

relative age

The age of a rock compared with ages of other rocks.


A type of fossil formed when minerals may slowly seep into the remains of living things, such as wood, and harden into a rocklike fossil.

carbon film

A thin coating of carbon that is left behind by a living thing.


The preserved remains or traces of past life found in some rocks.


Hardened tree sap; can preserve a whole animal


One huge landmass; all of the current continents were together.


A type of fossil formed when minerals fill the space left after an organism's remains dissolve.


The type of rock where most fossils are formed.

lowest layer

Where would you find the oldest fossils

millions of years

some animals haven't changed

the sea

When fossils of water creatures are found in land areas, you know the area was once. . .

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording