Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
The Theory of Plate Tectonics Theory of Plate Tectonics 1. Continents appear to “drift” with time 2. Lithosphere is broken up into rigid “plates”, that are moving 3. There are three types of plate boundaries: 1. Divergent 2. Convergent 3. Transform 3 types of plate boundaries: 1. Divergent – such as a mid ocean ridge where sea floor spreading occurs 2. Transform boundary – where 2 plates slide along side of one another 3. Convergent – where 2 plates collide A transform plate boundary Transform plate boundary Transform Boundary in California Close up of San Andreas Fault Transform boundaries also exist at offsets along the mid ocean ridge There are 3 types of convergent plate boundaries 1. Ocean plate and another ocean plate Example: the Aleutian trench 2. Ocean plate and a continental plate Example: Peru-Chile Trench 3. Continental plate and another continental plate Himalayan Mountains 2 oceanic plates collide Oceanic plate and a continental plate collide Ocean-continent convergent plate boundary Convergent Plate Boundary Ocean plate and continental plate Subduction is forming the Andes Mountains Two continental Plates collide Continent- continent convergent plate boundary India colliding with Asia Name this plate boundary Match the labels to the letters F E A B D Oceanic plate C The oceanic crust sinks under the less dense continental crust Continental crust Explosive volcanoes The oceanic crust melts and rises Mantle Hot Spot Another Hot Spot Yellowstone National Park In Summary: 1. The Earth’s surface is broken up into plates 2. The plates move a few centimeters per year in different directions 3. The plate boundaries may be classified into convergent or divergent or transform 4. Divergent plate boundaries are rift zones usually associated with a mid ocean ridge Convergent Plate Boundaries may be the following types 1. Two oceanic plates- resulting in a subduction zone and an island arc. Ex. Aleutian Islands and trench 2. An oceanic plate and a continental plate – resulting in a subduction zone and coastal mountains – ex. Andes Mtns. 3. Two continental plates – resulting in severe uplifting of the earth’s crust and a very large mountains like the Himalayas, or the Alps