The crust and the upper part of the mantle is called the LITHOSPHERE and it is RIGID, BRITTLE and behaves ELASTICALLY.The part of the mantle directly below the lithosphere is termed the ASTHENOSPHERE which behaves like a PLASTIC - a solid that flows.Match of coastlines across the Atlantic OceanMatch of rock formations across the Atlantic OceanDistribution of fossil species across continentsDistribution of climate sensitive sedimentary rocksSome evidence includes:Reversals of the Earth’s magnetic field are preserved in ocean-floor basalt, as matching symmetrical striped patterns parallel to the mid-ocean ridge.The youngest ocean-floor rock is at the ridge and the oldest ocean-floor rock is farthest away from the ridge.Hot spot volcanic islands show the direction of motion of the lithospheric plate over the mantle plume.Earthquakes and volcanoes are concentrated where plates interact at their boundaries.Old ocean floor sinks at subduction zones (trenches).Continent-Ocean Convergent Plate Boundary: Examples include the Andes Mountains in South America, the Cascade Mountains in Western USContinent-Continent Convergent Plate Boundary: Examples include the Appalachian Mountains formed during the formation of Pangaea, the Himalayas from the collision of India with Asia.Ocean-Ocean Convergent Plate Boundary: Examples include Japan, Aleutian islands, Caribbean islands, Mariana Islands,Ocean-Ocean Divergent Boundaries: Examples include: Mid-Atlantic Ridge spreading ~1 cm/yr; East Pacific Rise spreading ~6 cm/yr.Ocean-Ocean Transform Boundaries or Ridge-ridge transform boundaries: Major offsets of mid-ocean ridge axis.Continent-Continent Transform Boundaries: Examples include the San Andreas Fault, North Anatolian Fault.Melting of the subducting oceanic plate occurs because it is not stable under the high temperatures and pressures of the mantle, therefore it melts generating a (mafic) magma. The magma, being less dense than the surrounding solid mantle, rises up through the continental (felsic) crust. The end result is a volcanic arc paralleling the oceanic trenchName: _______________________Learning Unit 2: Plate Tectonics and Physical Hazards Review QuestionsThis assignment is designed to assess your understanding of Unit 2 and includes some of the Questions for Review at the end of Chapter 2 from your text plus a few additional questions. Each question can be answered in one to two sentences. Please limit yourself to a maximum of three sentences. Access the assignment, complete it with ANSWERS IN A DIFFERENT COLOR FONT as a separate file, and send it back for evaluation and grading through the assignment tab by or before the due date. 1. What forces drive internal and external Earth Processes?-Internal processes such as magma formation to create volcanoes and the storage ofstrain energy in rock to create earthquakes are driven by heat loss from Earth’s deep interior. External processes (processes resulting from the hydrologic cycle) take place near the surface or at the surface of the earth and are driven by gravity and energy from the sun.2. What energy sources caused the interior of the early Earth to heat up?-gravitational collapse, impact energy and radioactive decay3. List the density stratified layers of the earth from most dense to least dense.- Inner core- outer core- mantle- oceanic crust-continental crust4. The lithosphere is composed of what two layers?-Crust (oceanic and continental) and upper mantle5. Distinguish between Earth’s lithosphere and asthenosphere in terms of both location and properties.- The crust and the upper part of the mantle is called the LITHOSPHERE and it is RIGID, BRITTLE and behaves ELASTICALLY.- The part of the mantle directly below the lithosphere is termed the ASTHENOSPHERE which behaves like a PLASTIC - a solid that flows.6. Before people understood plate tectonics, what evidence led some scientists to believe in continental drift? - Match of coastlines across the Atlantic Ocean- Match of rock formations across the Atlantic Ocean- Distribution of fossil species across continents- Distribution of climate sensitive sedimentary rocks7. What was the primary reason why Alfred Wegener’s theory of continental drift rejected?-He had no viable mechanism for moving continental crust.8. What evidence confirmed seafloor spreading? Be brief but to the point Some evidence includes:- Reversals of the Earth’s magnetic field are preserved in ocean-floor basalt, as matching symmetrical striped patterns parallel to the mid-ocean ridge. -The youngest ocean-floor rock is at the ridge and the oldest ocean-floor rock is farthest away from the ridge.- Hot spot volcanic islands show the direction of motion of the lithospheric plate over the mantle plume.- Earthquakes and volcanoes are concentrated where plates interact at their boundaries.9. If the ocean floor is getting wider, why is the Earth not becoming larger? - Old ocean floor sinks at subduction zones (trenches).10.Why do many oceanic volcanoes occur as long lines of volcanoes that are active at only one end? -They are hotspot volcanoes. A hot plume of magma rising through the mantle burnsthrough the overlying lithosphere to erupt as a volcano. Since the lithosphere moves over the deeper mantle, new volcanoes form progressively in a line over the plume.11.What are the main types of lithospheric plate boundaries in terms of relative motions?Provide a real example of each.- Continent-Ocean Convergent Plate Boundary: Examples include the AndesMountains in South America, the Cascade Mountains in Western US- Continent-Continent Convergent Plate Boundary: Examples include the AppalachianMountains formed during the formation of Pangaea, the Himalayas from thecollision of India with Asia.- Ocean-Ocean Convergent Plate Boundary: Examples include Japan, Aleutianislands, Caribbean islands, Mariana Islands, - Continent-Continent Divergent Boundaries: Examples include: The break-up of Pangaea, The East African Rift Valley, Basin and Range of Nevada and Utah.- Ocean-Ocean Divergent Boundaries: Examples include: Mid-Atlantic Ridge spreading ~1 cm/yr; East Pacific Rise spreading ~6 cm/yr.- Ocean-Ocean Transform Boundaries or Ridge-ridge transform boundaries: Major offsets of mid-ocean ridge axis.- Continent-Continent Transform Boundaries: Examples include the San Andreas Fault, North Anatolian Fault.12.Why does oceanic lithosphere almost always sink beneath
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