Presentation on theme: "Chapter 17 Plate Tectonics"— Presentation transcript:
1 Chapter 17 Plate Tectonics Section 17.3The Theory of Plate Tectonics
2 Vocabulary Divergent Boundary: Convergent Boundary: A plate boundary where two plates move away from each other.Convergent Boundary:A plate boundary where two plates move toward each other.Transform Boundary:A plate boundary where two plates move past each other in opposite directions.
3 Vocabulary Plate: Plate Tectonics: A section of the lithosphere that slowly moves over the asthenosphere, carrying pieces of continental and oceanic crust.Plate Tectonics:The theory that pieces of Earth’s lithosphere are in constant motion, driven by convection currents in the mantle.
4 Vocabulary Fault: Rift Valley: A break in Earth’s crust where slabs of rock slip past each other.Rift Valley:A deep valley that forms where two plates move apart.
5 IntroductionThe lithosphere is broken into separate sections called __________.True or False: Plates can carry continents or parts of the ocean floor but not both.Falseplates
6 A Theory of Plate Motion What is a scientific theory?A scientific theory is a well-tested concept that explains a wide range of observations.State the theory of plate tectonics.Pieces of Earth’s lithosphere are in constant, slow motion, driven by convection currents in the mantle.True or False: The theory of plate tectonics explains the formation, movement, and subduction of Earth’s plates.True
7 Plate BoundariesTrue or False: Crust is both created and destroyed along a transform boundary.FalseMost divergent boundaries occur at the ________________.When two plates collide, what determines which plate comes out on top?The density of the plate determines which plate comes out on top.mid-ocean ridge
9 The Continent’s Slow Dance About how fast do plates move?Plates move from about one to ten centimeters per year.True or False: The pieces of the super continent Pangaea began to drift apart about 225 million years ago.True