Relative Dating

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Relative Dating

• Superposition
• Original Horizontality
• Faulting
• Tilting/Folding
• Intrusions
• Unconformities
• Geologic Columns
• Rock Puzzles

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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

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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!

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III. Disturbed Rock Layers Events are younger
than the rock layers

1. Faulting a break in the Earths curst where one
   rock layers will slide
2. Intrusions when molten rock squeezes into
   existing rock and cools
3. Folding Tilting When internal forces bend or
   tilt rock layers
4. Unconformities a surface that represents an
   area where there is a missing piece of geologic
   rock

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Faulting
Cross Cutting
Folding
Unconformity
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Faulting
Intrusions
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IV. Geochronology - the science of dating and
determining the time sequence of events in the
history of the Earth.

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IV. Geochronology - Key