Put these cars in age order. Put the oldest car on the bottom and...
Transcript of Put these cars in age order. Put the oldest car on the bottom and...
oldest
youngest
Put these cars in age order. Put the oldest car on the bottom and youngest car at the top.
A
E
D
C
B
B
A
D
E
C
Topic: Relative Dating
Put these recording devises in age order.
youngest
oldest
A
E
C
B
D
B
C
D
A
E
Relative Dating:
Age of a rock or event in relation to other rocks or events.
Principles of Relative Dating
The layers and jagged rocks of the reef, Capitol Reef , Utah
Orange Layer
Red Layer
Green Layer
1. Principle of Superposition - oldest rocks are at the bottom.
Superposition in the Grand Canyon
2) Original Horizontality: Rocks are usually deposited horizontally.
Taughannock Falls, NY - Horizontal Strata
Normal faults are nicely exposed at several points within the canyon walls. Red Rock Canyon State Park near Mojave, California
3. Law of Deformed Strata: Tilts, folds or faults are younger
than the rocks.
Folded Strata
Undeformed Strata
Faulted Strata
Tilted Strata
4. Cross-cutting relationships- Igneous intrusions are
younger than rocks they intrude.
Before the lava & magma cools
After the magma and lava cools
Igneous Intrusions causes Contact Metamorphism Contact metamorphism with pegmatite Orchard Beach, Bronx
Hot Magma touches surrounding rocks
Heat
Granite Intrusion
Pre-existing rock
Pre-existing rock
Contact Metamorphism: shown by hachure marks
5. Included fragments: Older rocks break off into younger layers
Limestone
Uplift
Weathering & Erosion
Curved, wavy surface shows erosion
Unconformity
6) Unconformity Buried erosional surface
wavy line with
layer on top.
Gap of time missing.
Put it together using the Principle of Original Horizontality and the Principle of superposition
What are the relative ages of the rocks in this section?
D
C
B
A oldest
youngest
FQ: Place the letters in order from oldest to youngest
____ Youngest
____
____
____
____
____
____Oldest G
F
E
D C
A
B
Sequence 1: Uplift & Erosion
5. Erosion
4. Uplift
3. Shale Deposited
2. Sandstone Deposited
1. Limestone Deposited
Sequence 2: Faulting
4. Faulting
3. Shale Deposited
2. Sandstone Deposited
1. Limestone Deposited
Sequence 3: Folding
4. Folding
3. Shale Deposited
2. Sandstone Deposited
1. Limestone Deposited
Sequence 4: Igneous Intrusion
4. Igneous Intrusion
(contact metamorphism)
3. Shale Deposited
2. Sandstone Deposited
1. Limestone Deposited