Continental-Continental Lithospheric Plates: Types of Tectonic Plate Boundaries Interactive Science Book pages 174-179 Name ______________________ Date _________ Type Direction of motion Constructive or Destructive? Description: Results of this plate action Transform boundary Divergent Boundary: Oceanic-Oceanic Divergent Boundary: Continental-Continental

Continental-Continental Type Direction of motion Description: Results of this plate action Constructive or Destructive? Convergent Boundary: Oceanic-Oceanic SUBDUCTION ZONE Convergent Boundary: Continental-Oceanic SUBDUCTION ZONE Convergent Boundary: Continental-Continental

Continental-Continental Type Direction of motion Constructive or Destructive? Description: Results of this plate action Tectonic plates are sliding past one another Earthquakes Ex: San Andres fault in CA-Pacific Plate sliding past N. American Plate Transform boundary Two tectonic plates are moving apart A mid-ocean ridge forms Ex: Mid-Atlantic Ridge- N. American/Eurasian plates diverging and S. American/African plates diverging Divergent Boundary: Oceanic-Oceanic Two plates moving apart rift valley forms As rift widens and drops the sea could eventually fill in over the land Ex: Great African Rift Valley in East Africa Divergent Boundary: Continental-Continental

Transform Fault

Mid-Atlantic Ridge Divergent Plate Boundary

Great African Rift Valley Divergent Boundary

Constructive or Destructive? Type Direction of motion Description: Results of this plate action Constructive or Destructive? Two oceanic plates come together & collide. The MORE dense plate will sink (subduct) under the less dense plate Ocean trenches form, island arcs form from the building of under water volcanoes, earthquakes can occur Examples: Japan (Phillipine/Pacific/Eurasian plates) Marianas Trench Aleutian Islands (N. American/Pacific Plates) Convergent Boundary: Oceanic-Oceanic

Constructive or Destructive? Type Direction of motion Description: Results of this plate action Constructive or Destructive? An oceanic plate and a continental plate collide. The more dense oceanic crust subducts under the continental crust. Rock that subducts into the hot mantle melts back into magma. Ocean trenches form at subduction zone Volcanic mountains on the continental side Example: 1) Andes Mountains (Nazca Plate subducting under the S. American Plate) 2) Cascade Mountains in WA & OR (Juan de Fuca Plate is subducting under the N. American Plate) **Mt. St. Helens Volcano** Convergent Boundary: Continental-Oceanic SUBDUCTION ZONE

Continental-Continental Type Direction of motion Description: Results of this plate action Constructive or Destructive? Two continental plates come together & collide. Neither is dense enough to sink so the collision squeezes the crust until it is forced upward. Folded mountains form Ex: Himalayan Mountains (Indian and Eurasian plates colliding) Convergent Boundary: Continental-Continental