Fossils - Test Study Guide

This set of flashcards covers key vocabulary and concepts related to fossils, types of rocks, and geological time.

Weathering

When rock is broken down into smaller pieces.

Erosion

When rock is moved or taken away from its original location.

Deposition

When rock or sediment is deposited or dropped in a new location.

Sedimentary Rock

Rock created when layers of dirt and sand are pressed together.

Metamorphic Rock

Rock created due to heat and pressure.

Igneous Rock

Rock created when lava or magma cools.

Fossil Record

The history of all fossils ever found on Earth.

Trace Fossil

A type of fossil that is only the evidence of an organism, not the organism itself.

True Form Fossil

A type of fossil where the entire organism is preserved in its original form.

Cast Fossil

A type of fossil formed when a mold is filled in, creating a solid copy of that organism.

Mold Fossil

A type of fossil that is a hollow impression left in rock after the organism decayed.

Relative Age

The age of something compared to the age of something else.

Absolute Age

The age of something when you give a specific number.

Law of Superposition

In undisturbed horizontal rock layers, the older rock layer is at the bottom.

Law of Cross-Cutting Relationships

If a fault or intrusion cracks a rock layer, the fault or intrusion is younger than the rock layer.

Index Fossil

Species that were widespread but lived for a short period of time, used to date other fossils or rocks.

Extinction

When all members of a specific species die out.

Mass Extinction

When a large number of species die within a relatively short period of time.

Behavior

How an organism acts in a specific situation.

Fossilization Steps

1. Rapid burial 2. Mineralization 3. Turns into stone/Compaction 4. Exposure.