Plate Tectonics – Day 3 Plate Boundaries 9/27/10

Objectives I will be able to compare and contrast the _______ at the three different plate boundaries. I will be able to give ________________ of the different plate boundaries.

Key Points A divergent boundary at two oceanic plates can result in a _______ boundary. New ________crust is formed at divergent boundaries An example of a divergent plate boundary on continental lithosphere would be the East African Rift Valley. A __________example of a transform fault boundary is the San Andreas Fault in CA. Volcanic island arcs are associated with a convergent _______________ boundary. An Oceanic-Continental convergent boundary forms a ______________zone. A subduction zone is when the oceanic lithosphere is forced underneath the continental lithosphere when they collide.

Actions at Plate Boundaries Remember, there are three types of plate boundaries… Explain what each of these mean in your own words. _________________ __________________

Actions at Plate Boundaries At every type of plate boundary, ______are happening that shape our planet. Let’s take a closer look and explore what happens at each of the plate boundaries.

Divergent boundaries A divergent boundary at two oceanic plates can result in a ________________. ____________________is formed at divergent boundaries. The action of __________________________on the ocean floor is called seafloor spreading. Seafloor spreading is the process by which plate tectonics _____________________________________.

Spreading Center of Divergent Boundaries

Divergent boundaries When plates move apart on a _________, the _________________into two or more smaller segments. These are called ___________________. An example of a ___________plate boundary on _______________lithosphere would be the ____________________________

East African Rift Valley

Convergent boundaries There are _______types of plates: _________________Plate – a plate of the lithosphere located on ______. A continental plate is usually ____________and __________than an oceanic plate. _____________Plate – a plate of the lithosphere located on the ocean floor. An oceanic plate is generally _________and more dense than a continental plate.

9.3 Actions at Plate Boundaries Convergent Boundaries 9.3 Actions at Plate Boundaries A subduction zone occurs when _____ ________________________________ ________________________________  Oceanic-Continental • Denser _______slab sinks into the _________________. • Pockets of magma develop and rise. • Geographic examples include the ___________, Cascades, and the Sierra Nevadas.

Oceanic-Continental Convergent Boundary

9.3 Actions at Plate Boundaries Convergent Boundaries 9.3 Actions at Plate Boundaries  Oceanic-Oceanic • _____________________ converge and one descends beneath the other. • This kind of boundary often forms ___________ on the ocean floor. • ____________________form as volcanoes emerge from the sea. • Geographic examples include the Aleutian, Mariana, and _________ islands.

Volcanic Hot spot – an island created out of a seafloor volcano Volcanic Arc Island

Oceanic-Oceanic Convergent Boundary How is the Oceanic-Oceanic boundary different from the Oceanic-Continental boundary? ________________________

9.3 Actions at Plate Boundaries Convergent Boundaries 9.3 Actions at Plate Boundaries  Continental-Continental • When converging plates are on _______, two _____________collide. • This kind of boundary can produce new _______________ranges, such as the _________________.

Continental-Continental Convergent Boundary

Collision of India and Asia

The Himalayas

9.3 Actions at Plate Boundaries Transform Fault Boundaries 9.3 Actions at Plate Boundaries  At a transform fault boundary, plates _______ past each other without destroying the lithosphere.

Transform Fault Boundary

Transform-Fault Boundary A geographic example of a transform fault boundary is the __________________in CA.

Check in What is a geographic example of a transform-fault boundary? What is an example of a divergent boundary on continental lithosphere? What kind of boundary creates volcanic island arcs? Which boundary causes seafloor spreading?

Draw and Describe Draw an oceanic-continental converging boundary. Label the drawing with the following terms: (pg. 261) Oceanic Crust Trench Continental volcanic arc Continental Crust Lithosphere Asthenosphere Melting Subduction Describe what happens as the continental plate converges with the oceanic plate in paragraph form. The paragraph must be at least 5 sentences in length.

Vocabulary You may use the rest of the time to work on your vocabulary for chapters 9 and 11. The vocabulary list is on the Earth Science Website. Download it and save it so you can access it even when you don’t have internet. This vocabulary list is due on FRIDAY!