Investigation 4 Science Vocab

Front

Era of recent animal life; mammals exist.

Back

Cenozoic

Front

Patterns in rocks from wind-blown sand dunes

Back

Cross bedding

Front

Surface revealed when cut through, typically at a right angle to its axis.

Back

Cross section

Front

Subdivision of a geological period

Back

Epoch

Front

A broad span of geologic time based on the type of life existing during that time.

Back

Era

Front

Rock layers with distinct characteristics and sediment sequences

Back

Formation

Front

Remains or traces of ancient life in Earth's crust

Back

Fossil

Front

All fossils on Earth

Back

Fossil record

Front

Time since Earth's formation (4.6 billion years ago)

Back

Geologic time

Front

A fossil that characterizes a specific time period

Back

Index fossil