5. What landform is created when two continental plates come together? DO NOW: Day #1 HW due Friday! 1. What is the difference between an oceanic plate and a continental plate? 2. What happens at a convergent plate boundary? 3. What is subduction? Why does it happen? 4. What landforms does subduction create?
Divergent Plate Boundaries
Types of Plate Boundaries Convergent plates move toward one another Transform plate moves sideways from each other Divergent plates move away from each other
Divergent Boundary (hand motion) When two plates move or spread apart from each other Connection/C.F.U.: What causes them to move apart from each other? http://www.classzone.com/books/earth_science/terc/content/visualizations/es0804/es0804page0 1.cfm?chapter_no=visualization
Instructional Video http://www.youtube.com/watch?v=y1r5g- UG_N8 (3:30 and 5:57) Listen carefully and take notes. See how much of the important information you can pick out
Two Oceanic Plates Diverging: - Cause the Sea-Floor to Spread - As plates spread, magma comes up and cools as it hits the ocean water and hardens forming new rock. - As new rock piles on top of each other, mountains form under the ocean called a mid-ocean ridge!
What does this actually look like? Video 1: http://www.videosurf.com/video/divergent-boundary-119597587 And Video 2: http://player.discoveryeducation.com/index.cfm?guidassetid=2ed78244-ed66-438c-b2dd-55c2d810c4a1&blnfromsearch=1&productcode=us
Newest/Youngest Rock As the plates spread and magma hardens to form rocks we get the newest crust on Earth. Baby infant rocks!
Two Continental Plates Diverging: -Creates a dip in the crust (valley) -These plates are thicker (not denser) very harder to crack. As they spread they sink creating a RIFT VALLEY and this valley can fill with water making a sea! --the Great Rift Valley, East Africa --the Red Sea
Stress The stress that occurs during a divergent boundary is called tension. Tension happens when the plates are being pulled apart from one another.
Draw and Label A Divergent Boundary Oceanic Continental
Ireland: Hikers walk in the shadow of cliffs. The divergent Mid-Atlantic Ridge rises above sea level, with the North American plate to the west and the Eurasian plate to the east.
Divergent Plates What happens What forms Oceanic Sea-floor spreading happens and magma comes up and cools forms new rock Mid-ocean ridges (Example: the Mid-Atlantic ridge) and new crust Continental Plates spread and then sink to form a basin (bowl shape) Rift valleys, (and Seas if filled with water) (Example: the Red Sea)
Review- Let s see what you know! What direction do the plates move in a divergent boundary? What is causing the plates to move? What 2 landforms are created during divergent boundaries? How does new rock form?
DO NOW: Day #2 HW due Friday! 1. What is a divergent boundary? 2. When 2 oceanic plate diverge, what does it cause? What forms from 2 oceanic plates diverging? 3. When 2 continental plates diverge, what does it cause? What forms from 2 continental plates diverging? 4. How do we get new rocks to form? (Hint: think about magma)
Review- Let s see what you know! What direction do the plates move in a divergent boundary? What is causing the plates to move? What 5 landforms are created during divergent boundaries? How does new rock form?
Divergent Plates What happens What forms Oceanic Sea-floor spreading happens and magma comes up and cools forms new rock 1. Mid-ocean ridges Example: the Mid- Atlantic ridge 2. Sea-floor spreading 3. New rock Continental Plates spread and then sink to form a basin (bowl shape) 4. Seas Example: the Red Sea 5. Rift Valley
Divergent Foldable- 3 tabs Tab 1: Name of boundary, Definition of a divergent boundary, drawing with arrows, type of stress this boundary undergoes. Tab 2: Oceanic- Oceanic Description of what is happening. Are these plates on land or under water? What 3 landforms are made from these 2 plates How are these landforms made? Tab 3: Continental- Continental Description of what is happening. Are these plates on land or under water? What 2 landforms are made from these 2 plates How are these landforms made?
Exit Ticket