Fossils and Geologic Time Scale

Front

What is a cast fossil?

Back

A cast fossil is a type of fossil that looks just like the body part of a once-living thing, formed when minerals fill in the mold of an organism.

Tags

NGSS.MS-LS4-1

Front

What is a mold fossil?

Back

A mold fossil is the impression left by an organism, showing the shape of the organism without any actual material from it.

Front

What is radiometric dating?

Back

Radiometric dating is a method used to determine the age of rocks by comparing the amounts of unstable, radioactive particles to stable particles in a sample.

Tags

NGSS.HS-ESS1-6

NGSS.HS-PS1-8

Front

What does the fossil record provide evidence for?

Back

The fossil record provides evidence for the history of life on Earth, showing how different organisms have existed over time.

Tags

NGSS.MS-LS4-1

Front

Which layer of rock is typically the oldest?

Back

In a sequence of sedimentary rock layers, the bottom layer is typically the oldest.

Tags

NGSS.MS-ESS1-4

Front

What is relative dating?

Back

Relative dating is a method used to determine the age of rocks by comparing their placement in layers, without determining their exact age.

Tags

NGSS.MS-ESS1-4

Front

What is petrified wood?

Back

Petrified wood is a type of fossil that forms when plant material is buried by sediment and then replaced by minerals, turning it into stone.

Tags

NGSS.MS-LS4-1

Front

What is the geologic time scale?

Back

The geologic time scale is a system used by geologists and paleontologists to describe the timing and relationships of events in Earth's history.

Tags

NGSS.MS-ESS1-4

Front

What are index fossils?

Back

Index fossils are fossils of organisms that were widespread but only existed for a short period of time, used to date the rock layers in which they are found.

Tags

NGSS.MS-LS4-1

Front

What is the significance of the Cambrian Explosion?

Back

The Cambrian Explosion refers to a period in Earth's history when a rapid diversification of life forms occurred, leading to the appearance of many major groups of animals.

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2