CFE Review #7: Geologic Time

Front

What is the primary component that all plants and animals contain?

Back

Carbon.

Front

What method do geologists use to determine the absolute age of rocks?

Back

Radioactive dating.

Front

According to the law of superposition, which layer is older: Layer A or Layer C if Layer A is above Layer C?

Back

Layer C is older than Layer A.

Front

What does the law of superposition state about sedimentary rock layers?

Back

In undisturbed layers, the oldest layers are at the bottom and the youngest are at the top.

Front

What is the definition of absolute age in geology?

Back

The age of a rock determined by radioactive dating.

Front

What is relative dating in geology?

Back

Determining the age of rocks and fossils in relation to one another, rather than in years.

Front

What is the significance of fossils in understanding geologic time?

Back

Fossils provide evidence of the history of life and can help date the layers of rock in which they are found.

Front

What is a half-life in the context of radioactive dating?

Back

The time required for half of the radioactive atoms in a sample to decay.

Front

What is the difference between absolute age and relative age?

Back

Absolute age is the actual age of a rock, while relative age is its age compared to other rocks.

Front

What is stratigraphy?

Back

The study of rock layers (strata) and layering (stratification).