DateSession #ActivityPage # 11/7,103Earth’s Interior Review4 Continental Drift5 Plate Tectonics6 11/12-134Subduction6 Plate Boundary Summary6 Plate Boundary Map7 Earth’s future quick write8 Homework: Read 22A-28A ?’s 3,5 on 28A Read 30A-36A ?’s 1-4 on p41A

Warm up -- tape diagram to page 7 of notebook Label: convergent oceanic-oceanic boundary, convergent oceanic-continental boundary, divergent boundary, mid-ocean ridge, coastal volcanic mountains, island arc, convection currents Oceanic crust Continental crust

Essential Standard 8.E.2 Understand the history of Earth and its life forms based on evidence of change recorded in fossil records and landforms. 8.E.2.2 Explain the use of fossils, ice cores, composition of sedimentary rocks, faults, and igneous rock formations found in rock layers as evidence of the history of the Earth and its changing life forms

Obj: TLW describe the evidence supporting the theory of continental drift by completing organizers using information from lecture, video, and demonstrations, then explain in a quick write why the circumference of the earth isn’t getting larger.

Earth’s Interior Structure p4

Continental Drift p5

Wegener’s Evidence Wegener noticed that earth’s continents appeared to fit together like a puzzle. He hypothesized that they were once joined as a single landmass – Pangaea Evidence: 1.Matching Fossils in S. America and W. Africa – nowhere else in the world 2.Climate: tropical plant fossils found in Greenland, near the arctic circle, and Antarctica. South African rock formations show evidence of ice sheet scratches 3.Matching Rock Layers/Mountains in S. America match those in W. Africa. Appalachian Mtns have limestone similar to Scotland’s Highlands

Pangaea

Sea Floor Spreading Scientists mapping ocean floor found huge underwater mountain ranges—Mid Ocean Ridges 1.Ridges form along cracks in the crust. Molten rock rises through crack, forms new crust, older material is pushed away from the crack. Crust created. 2.Drilling samples of sea floor reveal youngest rock is closed to the ridge, oldest is furthest. Oldest ocean floor is younger than continental crust. 3.Ocean trenches found far from ridges. Oceanic crust sinks under continental crust and melts into asthenosphere. Crust destroyed

Magnetic Reversals Earth’s poles reverse every 200, ,00 years. Minerals in magma rising through the mid ocean ridge align themselves with earth’s magnetic pole. As the rock cools, the minerals stay fixed in this position, like a compass needle The “stripes” of rock along the ocean floor record these reversals and are symmetrical to the mid ocean ridge. Demo description

Plate Tectonics Plate Tectonics p6 Earth’s lithosphere is broken into huge plates Earth’s lithosphere is broken into huge plates that move over the surface of the Earth. The movement is due in large part to convection currents in the mantle’s asthenosphere.

1. Convergent 2. Divergent 3. Transform TECTONIC PLATES There are 3 types of plate boundaries

TECTONIC PLATES The Lithosphere broken into many large and small slabs of rock called tectonic plates and where two plates meet, a lot of changes can occur.

Key word: Divide DIVERGENT

What occurs at this boundary? – New Crust Forms – Mid-ocean ridges – Rift valleys – Volcanoes – Earthquakes DIVERGENT

Divergent Boundary African Rift Valley

Divergent Boundary Mid Atlantic Ridge

Key word: Collide 3 types of convergent: (based on types of crust at the boundary) – Continental-continental – Oceanic-oceanic – Oceanic- continental CONVERGENT

CONVERGENT: CONVERGENT: CONTINENTAL-CONTINENTAL

What occurs at this boundary? – Folded mountains – Earthquakes CONVERGENT: CONTINENTAL-CONTINENTAL

Zagros Mountains, Iran

Convergent Boundary Continental Plate – Continental Plate Himalayan Mountains

CONVERGENT: OCEANIC-OCEANIC OCEANIC-OCEANIC

What occurs at this boundary? – Deep-ocean trenches – Subduction zone – Volcanic island arcs – Earthquakes CONVERGENT: OCEANIC-OCEANIC

Aleutian Islands (Alaska)

Japan

CONVERGENT: OCEANIC- CONTINENTAL

What occurs at this boundary? Deep-ocean trenches Subduction zone Coastal volcanic mountains Earthquakes CONVERGENT: OCEANIC- CONTINENTAL

Andes Mountains South America

When one plate sinks under another plate CAN ONLY HAPPEN when an oceanic plate is involved… Continental & oceanic plate collide = oceanic plate ALWAYS sinks because it is more DENSE. Oceanic & oceanic plate collide = the older more dense plate sinks! SUBDUCTION? What is Subduction?

Key word: Slide TRANSFORM

What occurs at this boundary? Faults Earthquakes TRANSFORM

Transform Boundary San Andreas Fault California

/students/simulations/SEPUP_Plate _simulation.swf /students/simulations/SEPUP_Plate _simulation.swf PLATE MOTION SIMULATION

Then there are Hot SpotsHot Spots Usually located far from plate boundaries Created when a plume of magma rises and melts the crust above it. As the plate moves, the hot spot stays, creating a series of volcanic islands or volcanoes Examples: Hawaiian Islands, Yellowstone Screen, shaving cream example

Demo, add description to notes

Plate boundary interactions

Sea Floor Spreading Lab Read the directions Complete the activity Answer questions completely

On pg. 7 of your IN…. Using the plate boundary map 1.Create a color coded key for each type of plate boundary 2.Find and color a segment of each of the three types of convergent boundaries on the map, label with type (o-o, o-c, cc) and land form 3.Find and color a segment of a divergent boundary on your map, label land form created. (If you can find two divergent boundaries, one on land and one beneath the sea…even better!) 4.Find and color a segment of a transform boundary on your map 5.Find and color a hot spot

Map Reading Convergent Boundary:Divergent Boundary continental – continental (c-c)Transform Boundary continental – oceanic (c-o) oceanic – oceanic (o-o) Hot Spot

Billions of years in the future, Earth’s core will have completely cooled. How will this affect earth’s surface?