Copyright © 2007 Pearson Prentice Hall, Inc. 1 Continental Crust Thicker Less dense Older (up to 4 billion) vs Oceanic Crust Thinner More dense Younger (< 220 Million Figure 13-7
Copyright © 2007 Pearson Prentice Hall, Inc. 2 Continental Crust Thicker Less dense Older (up to 4 billion) vs Oceanic Crust Thinner More dense Younger (< 220 Million) Figure 13-7
Copyright © 2007 Pearson Prentice Hall, Inc. 3 Continental Crust Thicker Less dense Older (up to 4 billion) vs Oceanic Crust Thinner More dense Younger (< 220 Million) Figure 13-7
Nature of the Ocean Floor: Topography Convergent Boundaries = Trenches
Nature of the Ocean Floor: Topography Mid Ocean Ridges = Divergent Boundaries
Copyright © 2007 Pearson Prentice Hall, Inc. 6 Figure 13-7 Continents grow by collisions Forming mountains at continent-continent convergent boundaries
Copyright © 2007 Pearson Prentice Hall, Inc. 7 Continents grow by collisions Forming mountains at continent-continent convergent boundaries Ex. India & Asia
Copyright © 2007 Pearson Prentice Hall, Inc. 8 The continents move through time. 225 million years ago they combines into one supercontinert called “Pangea”
Copyright © 2007 Pearson Prentice Hall, Inc. 9
10 Cascadia subduction zone
Copyright © 2007 Pearson Prentice Hall, Inc. 11 Cascadia subduction zone
Copyright © 2007 Pearson Prentice Hall, Inc Earth Quakes in the Cascadia subduction zone Note zone with few E.Q.s = locked = potential for very large quake (9.0+)