Lab 4: The movement of the Earth’s Lithospheric Plates

One Plate Subducts A trench forms above the subduction zone in water A volcanic island arc forms on the plate that is not subducted Ocean – Ocean Convergence

Ocean plate is subducted below continent. A trench forms above the subduction zone in water A volcanic mountain chain forms on land Ocean – continent Convergence

No subduction because continents are less dense than the mantle Continents collide and fold up (crunch) to form mountains continent – continent Convergence

Ocean – Continent Convergence 1. A. When an ocean plate converges with a continental plate, what happens? (Which plate subducts?) Explain. B. What is a subduction zone? C. What feature is found on the earth directly above the subduction zone? D. What feature forms on land? Explain.

Ocean – ocean Convergence 2.A. When two ocean plates collide, what happens? B. What feature is found on the earth’s surface directly above the subduction zone? C. What feature forms on the ocean plate that is not subducted? Explain.

Continent– Continent Convergence 3.A. When two continents collide, what happens? B. What feature forms on the earth’s surface because of the collision? C. Why don’t continents go down at the subduction zones?

Lab 4: VOCABULARY

11. Continental Crust Thicker, less dense, older lithospheric plate 49. Oceanic Crust Thinner, more dense, younger lithospheric plate

15. Continent-Continent Collision Zones Areas where two plates of the same density (continental crust) move toward each other and collide 46. Subduction The movement when one plate (oceanic crust) dives below another plate into the mantle