Download presentation
Presentation is loading. Please wait.
Published byLorin Hudson Modified over 9 years ago
1
Structure of a Continent Figure 13-3
5
How are continental plates formed? Figure 13-4
10
Continent-Ocean Collision
12
Ocean-Ocean Collision
13
Antilles Arc
14
Subduction Zone Jump
15
Granite plutons begin deep within an orogenic belt. How do they get to the surface? Erosion and Isostatic Rebound!
16
Discovery of the “roots” of mountains:
17
“Airy”-style isostasy: density is the same, but the thickness varies (ice cube model) (Good for continental mountains)
18
“Pratt”-style isostasy: lateral density varies (Good for mid-ocean ridges)
20
Ocean gravity map gives seafloor bathymetry.
21
World topography is mostly in isostatic equilibrium, but not always.
22
Geoid (meters), from GRACE satellite data
32
Tectonic history of North America
34
Eastern Terranes
35
Highlight 13-2 Tectonic history of North America: Growth of the Appalachians
36
Geometry of the Pacific – North America plates
37
Western Terranes
38
Western Terranes: The Rockies
39
But subduction is much more shallow than this picture shows!
40
Where does heating come from? Western Terranes: Basin and Range
46
Canadian Rockies Appalachians Alps
47
Volcanism adds rock to continental volume.
50
Hotspot volcanism often begins with a large basaltic flood.
51
Afar hotspot
52
Columbia flood basalts
53
Columbia flood basalts: Beginning of Yellowstone hotspot
54
Shape of Atlantic Ocean determined by Iceland hotspot
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.