Relative and Absolute Dating

Front

What is relative dating?

Back

Relative dating is a method used to determine the age of rocks and fossils in relation to one another, without providing a specific numerical age.

Front

What is absolute dating?

Back

Absolute dating is a method used to determine the exact age of a rock or fossil, usually expressed in years.

Front

What does the law of superposition state?

Back

The law of superposition states that in undisturbed sedimentary rock layers, the oldest layers are at the bottom and the youngest layers are at the top.

Front

What is a half-life?

Back

A half-life is the time required for half of the parent isotope in a sample to decay into a daughter isotope.

Front

How do you calculate the percentage of parent isotope remaining after 2 half-lives?

Back

After 2 half-lives, 25% of the parent isotope remains.

Front

What is an unconformity in geology?

Back

An unconformity is a gap in the geological record where rock layers are missing due to erosion or non-deposition.

Front

What is a fault?

Back

A fault is a fracture or zone of fractures in rock along which movement has occurred.

Front

What is an intrusion?

Back

An intrusion is a body of igneous rock that forms when magma cools and solidifies within pre-existing rock layers.

Front

What is the difference between relative age and absolute age?

Back

Relative age indicates whether one rock is older or younger than another, while absolute age provides a specific age in years.

Front

What is the significance of the parent isotope in radiometric dating?

Back

The parent isotope is the original radioactive isotope that decays into a stable daughter isotope over time.