Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

21 Cards in this Set

  • Front
  • Back


The preserved remains or traces of living things


A hollow area in sediment in the shape of an organism or part of an organism

Petrified fossils

Fossils in which minerals replace all of an organism or a part such as a dinosaur bone

Carbon film

An extremely thin coating of carbon on rock that left from an organism

Trace Fossils

A type of fossil that provide evidence of the activities of ancient organisms. For example, a a footprint, an animal trail, or burror

Preserved Remains

A fossil that is formed when an organism becomes trapped in sticky tar or tree resin. Freezing very long periods of time can also sometimes create this kind of fossil.


A scientist that studies fossils

The fossil record

A record that provides evidence about the history of life and past environments on Earth.


The change in living things over time


A type of organism that no longer exists and will never be alive again on Earth


Rock particles or the remains of living things


an animal, plant, or single-celled life form (something that is or was once alive)

absolute age

the number of years that have passed since the rock formed. (Example: this rock is 2.3 million years old)

law of superposition

states that the oldest layer is at the bottom and each higher layer is younger than the layer below it (in undisturbed horizontal layers of sedimentary rock)


Lava that hardens as igneous rock on the surface (it is always younger than the rocks below it)


Magma that pushes into bodies of rock below the surface and cools and hardens into igneous rock (it is always younger than the rock layers around and beneath it)


a break in the Earth's crust (always younger than the rock it cuts through)

index fossil

fossils that help geologists match rock layers from separate locations (they tell the relative age of the rock layers in which they occur)


a gap in the geologic record showing where rock layers have been lost due to erosion


where rock layers have been bend and turned over

Relative Age

the age of a rock compared to the ages of other rocks