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Convergent Plate Boundary

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Convergent Plate Boundary November 17, 2020 Yá’át’ééh! sha'áłchíní Welcome to science class! August 27, 2020 Sun. Mon. Tues. Wed. Thurs. Fri. Sat. 1 2 3 4 5 6 7 Tutoring 6:00PM-7:00PM 8 9 10 11 12 Packets 13 14 ready for PTC pick up 4-7PM 15 16 17 18 19 20 21 Class TMS Community Tutoring Forum 5:30pm cancelled 6:00PM-7:00PM 22 23 24 25 26 27 28 29 30 Weekly Vocabulary Agenda -continental drift ● Announcement -plate tectonics -convergent plate ● Class Discussion boundary ● Review Vocabulary -divergent plate ● Force Activity boundary -transform plate ● Exit Ticket boundary -subduction -convection -ridge pull -slab pull Student Friendly Objective VocabularyVocabulary -continental-continental drift I can explain why tectonic plates -platedrift tectonics -convergent plate move by knowing the forces that -Pangaea boundary cause plate motion. -divergent-fossils plate boundary-plate -transform plate tectonics ***Write in agenda/planner. (1 min.) boundary-rocks -subduction-minerals -convection -ridge-Earth’s pull crust -slab-continental pull VocabularyVocabulary Announcements -continental-continental drift -platedrift tectonics -convergent plate -Pangaea ● Thurs., Nov. 19th- Tutoring! boundary ● Thurs., Nov. 19- QUIZ -divergent-fossils plate boundary-plate ● 11/23-11/27- Thanksgiving Break! -transformtectonics plate boundary-rocks TEXT 928-366-2711 -subduction-minerals -convection EMAIL [email protected] -ridge-Earth’s pull crust -slab-continental pull Weekly Vocabulary Essential Question(s) -continental drift How do movements at plate -plate tectonics -convergent plate boundaries form different landforms? boundary DOK2 -divergent plate boundary What are Earth’s outermost layers -transform plate boundary called? DOK1 -subduction -convection -ridge pull -slab pull Weekly Vocabulary Class Discussion -continental drift Compare and Contrast the -plate tectonics -convergent plate oceanic and continental crust. boundary -divergent plate boundary -transform plate boundary -subduction -convection -ridge pull -slab pull Weekly Vocabulary Class Discussion -continental drift Compare and Contrast the -plate tectonics -convergent plate oceanic and continental crust. boundary -divergent plate boundary -transform plate boundary -subduction -convection -ridge pull -slab pull Oceanic crust is found under oceans, and it is about four miles thick in most places. A feature unique to oceanic crust is that there are areas known as mid-ocean ridges where oceanic crust is still being created. Magma shoots up through gaps in the ocean’s floor here. As it cools, it hardens into new rock, which forms brand new segments of oceanic crust. Since oceanic crust is heavier than continental crust, it is constantly sinking and moving under continental crust. Continental crust varies between six and 47 miles in thickness depending on where it is found. Continental crust tends to be much older than the oceanic kind, and rocks found on this kind of crust are often the oldest in the world. Examples of such rocks are those in Quebec, Canada which are estimated to be about 4 billion years old. What is the difference between Oceanic and Continental Crust? 1. Oceanic crust is dominated by mafic and ultramafic intrusive igneous rocks whereas continental rocks are dominated by granitic (felsic) intrusive igneous rocks. 2. The difference in density has an impact on isostacy of crust floating on the semi-fluid upper mantle (asthenosphere), with continental crust (about 2.7g/cm3) rising or floating above oceanic crust (about 3.5 g/cm3). 3. The continental crust is by far the older of the two types of crust. 4. The mantle, oceanic crust, and continental crust all have different compositions due to a process called partial melting. 5. Because continental crust is less dense than oceanic crust it floats higher on the mantle, just like a piece of Styrofoam floats higher on water than a piece of wood does. FORCES convection: is the circular motion that happens when warmer air or liquid — which has faster moving molecules, making it less dense — rises, while the cooler air or liquid drops down. For example, the upstairs floors of homes are often warmer because hot air rises. Hot air is less dense than cold air. As the cold air sinks, the hot air rises. Basal Drag Convection currents in the mantle produce a force on plates that causes motion called basal drag. Convection currents in the asthenosphere can drag the lithosphere. This is similar to how a conveyor belt moves items at a supermarket. ridge push: when the rising mantle material at mid-ocean ridges creates the potential for plates to move away from the ridge with a force slab pull: when a slab sinks and pulls on the rest of the plate with a force plate tectonics Each of the several Tectonics (from Latin tectonicus; rigid pieces of the from Ancient Greek τεκτονικός earth's lithosphere (tektonikos) 'pertaining to which together make building') are the processes that up the earth's surface. control the structure and properties of the Earth's crust and its evolution through time. ... A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Plate size can vary greatly, from a few hundred to thousands of kilometers across; the Pacific and Antarctic Plates are among the largest. Three Types of Plate Boundaries Divergent Plate Boundaries forms where two tectonic plates separate Landform: Rift Valley, Sea floor spreading Example: Great Rift Valley in Africa and Mid Ocean Ridge Divergent Plate Boundaries forms where two tectonic plates separate Convergent Plate Boundary forms where two plates collide Landform: Mountain building, Deep-ocean trench Example: Indo-Australian plate and Eurasian plate to form Himalayas Mountains (Mt. Everest) subduction: the process by which the denser plate sinks below the more buoyant plate when two plates collide Convergent Plate Boundary forms where two plates collide At convergent margins, continents grow as plates are consumed. Three types of Convergent Boundaries 1. Convergent boundary between continental and oceanic crust results to subduction, volcanoes, and trenches. 2. Convergent boundary between two oceanic crust results to subduction, and the trenches formed are deeper like the Marianas Trench, which can sink Mt. Everest. 3. Convergent boundary between two continental crust results to building up the rocks forming mountains like the Appalachian and Himalayas mountain ranges. Convergent Plate Boundary forms where two plates collide Transform Plate Boundary forms where two tectonic plates slide past each other Landform: Earthquakes and faults Example: San Andreas Fault in California Transform Plate Boundary forms where two tectonic plates slide past each other Weekly Vocabulary EXIT TICKET -continental drift 1. Explain: What is the driving force of tectonic -plate tectonics plates? -convergent plate 2. A seventh grade scientist was climbing Mt boundary Everest, the tallest mountain in the world. At -divergent plate the top of the mountain they found a fossil of boundary an organism that once lived in the ocean. -transform plate boundary Explain how that is possible. -subduction -convection -ridge pull -slab pull.
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