Pages within Topic Outlines

Geologic Time

Terms to learn:

uniformitarianism   relative dating               original horizontality                     superposition         cross-cutting                 inclusions
disconformity         angular unconformity     nonconformity
isotope                  half-life

Topic outline:

Geologic time
Uniformitarianism
Relative Dating methods
1. Several important principles:
  1. Original Horizontality
  2. Superposition
  3. Cross-cutting relationships
  4. Inclusions
  5. Contact metamorphism
2. Unconformities
3. 1. Disconformity
  2. Angular unconformity
  3. Nonconformity
Absolute (Radiometric) Dating methods
1. Isotopes - radioactive decay
2. Half-life – parent isotope - daughter product
Geologic Time Scale

Interesting places to visit:

Lots of info about various periods in geologic time: http://www.ucmp.berkeley.edu/exhibit/geology.html

A pictorial history of life through geologic time: http://seaborg.nmu.edu/earth/Life.html

Fun dinosaur site with games: http://www.bbc.co.uk/dinosaurs/

USGS website on geologic time: http://wrgis.wr.usgs.gov/docs/usgsnps/gtime/gtime1.html

When you are finished with this topic, you should be able to answer the following questions:

If you find 75% of a parent isotope in a rock and 25% of the daughter, how many half-lives have passed?
Why is uniformitarianism important?
What are examples of each of the principles of relative dating?
What is an unconformity, how many types are there, and how are they formed?

Housing

Geologic Time