1. Original Horizontality
Relative Dating
Superposition
Original Horizontality
Faulting
Tilting/Folding
Intrusions
Unconformities
Geologic Columns
Rock Puzzles

2. I. RELATIVE DATING: Determining whether an object or an event is older or younger than other objects or events.
Relative Age?
Layer 1
Layer 2
Layer 3
Layer 4

3. II. SUPERPOSITION: Younger rock lie above older rock.
A. Law of Original Horizontality – Sedimentary rocks form layers of horizontal strata.
List the rocks in order from youngest to oldest!

4. III. Disturbed Rock Layers: Events are younger than the rock layers
Faulting – a break in the Earth’s curst where one rock layers will slide
Intrusions – when molten rock squeezes into existing rock and cools
Folding & Tilting – When internal forces bend or tilt rock layers
Unconformities – a surface that represents an area where there is a missing piece of geologic rock

5. Cross Cutting
Faulting
Folding
Unconformity

6. Faulting
Intrusions

7. IV. Geochronology - the science of dating
and determining the time sequence of
events in the history of the Earth.

8. IV. Geochronology - Key