16. National Parks Flashcards
1
Q
How old is the grand canyon?
A
5-6 million years old
fairly recent
2
Q
What is the colorado plateau
A
- area of land that formed 20 million years ago
- crust stretched, forming valleys and elongating mountains; uplifted 3km, cutting streams deeper into channels
- have arches, entrada sandstone
3
Q
What are arches in colorado plateau made of?
A
sandtone: weathered quartz sediment
4
Q
What is entrada sandstone?
A
layers of sediment that formed arches
sorted through wind- aeolian
formed during jurassic period (200-145 Ma)
5
Q
When did dinosaurs live?
A
65-70 Ma
6
Q
what are salt domes?
A
- salt is light and rises, pushing up rock
- salt exposed to rain, dissolves, rock collapses into salt domes
7
Q
When was yellowstone explored by europeans?
A
lewis and clark (john colter)
200 years ago
8
Q
when was yellowstone properly explored?
A
1869
9
Q
What is yellowstone known for?
A
world’s first national park
10
Q
How many national parks are there globally?
A
6000
