Geology: Age and Dating Methods

Who are geologists?

• Scientists who study the origin, history, and the structure of the Earth

• People who study stars and planets

• Experts in animal behavior

• Scientists who treat human diseases

What is the fact that geologists need to know?

• Age of rocks

• Color of the sky

• Number of continents

• Speed of light

What are two ways to communicate age?

• Relative age, Absolute age

• Physical age, Chemical age

• Modern age, Ancient age

• Direct age, Indirect age

• Numeric age, Symbolic age

What does 'relative age' express?

• The order, sequence of events; tells if it is younger or older

• The exact number of years since formation

• The chemical composition of a rock

• The temperature at which a rock was formed

What is 'absolute age'?

• Numerical or absolute time; includes a number and a unit of time such as years, days, or seconds

• The relative order of events without exact dates

• The process of fossilization in rocks

• A method to measure the temperature of ancient climates

What is the principle of uniformitarianism?

• Geologic processes that occur today are similar to those that have occurred in the past. Same processes that we see today have been occurring since the Earth formed.

• Geologic processes only occurred in the past and do not happen today.

• Geologic processes are completely random and unpredictable.

• Geologic processes are caused only by catastrophic events.

How does the principle of uniformitarianism help scientists?

• They can learn about Earth’s past by studying the present by studying the order in which geologic events occurred using a method called relative-age dating. event.

• They can predict future earthquakes with absolute certainty.

• They can create new elements in the laboratory.

• They can determine the exact age of every rock on Earth.

What is absolute dating?

• Technique to determine the exact age (numerical age) of artefact or site using methods (carbon dating)

• Method to estimate the relative position of artefacts in soil layers

• Process of preserving artefacts for future study

• Technique to identify the material composition of artefacts

What is relative dating?

• Technique to determine which object is older in comparison to the other (arranges fossils in an order)

• Method to measure the exact age of a fossil using radioactive isotopes

• Process of creating fossils from living organisms

• Technique to identify the chemical composition of rocks

Which principle states that undisturbed rock layers have the oldest rocks on the bottom?

• Superposition

• Uniformitarianism

• Cross-cutting Relationships

• Original Horizontality