Warm-Up. Explain why the Earth is like a chocolate chip cookie that was recently taken out of the oven. Mmm Earth Cookie

Transcription

1 Warm-Up Explain why the Earth is like a chocolate chip cookie that was recently taken out of the oven Mmm Earth Cookie

2 New Area of Focus: Layers of the Earth

3 Learning about the earth s interior. The force behind our planet.

4 Some of the surface temperature of Earth comes from the hot magma inside.

5 This magma is constantly moving and changes the surface of Earth over long periods of time

6 The Earth s interior even protects us from harmful solar radiation.

7 What is this a picture of? (Yes, I know it s a pencil In a glass of water! I mean the bending light thing)

8 What is this a picture of? (Yes, I know it s a pencil In a glass of water! I mean the bending light thing) Refraction! All waves do this when They travel through different mediums.

9

10

11 We know the material of the interior of the Earth based on how earthquake waves move through the planet.

12 Layers of the Earth

13 Earth s layers formed early in Earth System History. (Archean Eon)

14 Earth s layers formed early in Earth System History. (Archean Eon) What is the black stuff going to the center?

15 Earth s layers formed early in Earth System History. (Archean Eon) Answer: Iron (Core)

16 Earth s layers formed early in Earth System History. (Archean Eon) Why Did the iron sink to the center?

17 Earth s layers formed early in Earth System History. (Archean Eon) Answer: Gravity! (iron is heavy)

18 Inner Core: Solid Iron and Nickel (Dense).

19

20 Should you touch this? Why? It just came out of the fire.

21 Answer! No, you will burn your hand. Dense metal such as iron takes a long time to cool. Our Earth has been hot for a long time because it is one big piece of hot iron.

22 Hot and Dense Less Hot and Dense

23 Hot and More Dense Less Hot and less Dense

24 Temperatures and thicknesses are approximate 5-30km 3,000km 2,000 km 1,000 km

25 The spinning inner cores of solid and liquid Iron creates a giant electromagnetic field.

26 The EM field creates a kind of force field against charged particles from hitting Earth.

27 Electromagnetic field protects the Earth from charged particles. It also creates the Aurora borealis (Northern Lights)

28 Outer Core: Liquid Iron and Nickel

29 Mantle: Composed of Magnesium Silicates, Iron, Calcium - Asthenosphere (Outer Mantle) - Lithosphere (Lower Crust)

30 Asthenosphere

31

32 Answer! The light blue arrows should be diverging instead of converging.

33 Activity! Please make a puzzle from a magazine page. Puzzle should be no more than 20 pieces. Example on next slide. Trade puzzles with a person near you and try to solve their puzzle.

34

35 Question? Look at the map below, do see any puzzle pieces, if so were would they fit?

36 Possible Answers!

37 Area of Focus: Plate Tectonics

38 Plate tectonics: The Earth s crust and upper mantle are broken into sections called plates. These plates float on the mantle like rafts (moving very slowly)

39 Continental Drift: The gradual movement of the continents across the Earth.

40 The speed at which the plates move is about the speed at which your fingernails grow.

41 In 1915, The German geologist Alfred Wegener ( ) proposed continental drift. Not accepted until 1950 s! I say. Africa and South America fit strangely like two puzzle pieces.

42 Evidence for continental drift

43 The shapes match.

44 The puzzle pieces actually fit together at the end of the continental shelf.

45 Activity! Google Earth. Looking more in depth at the puzzle fit. Continental shelf

46 Same fossils found on different continents These are the pictures on the puzzle pieces.

47 Same fossils found on different continents These are the pictures on the puzzle pieces.

48 Did you line up the pictures on the magazine page to help you figure out the puzzle

49 The Same rock structures on different continents

50

51 This is a fossilized tropical plant found on Antarctica. Remember, the continents have moved and Antarctica use to be in a warmer climate. That s a bummer! Darn you continental drift.

52 Fossils of plants and animals in Antarctica

53 Magnetic layers in sea floor spreading

54 The magnetic poles can shift fairly suddenly on this planet. Right now, North is in the Arctic, the North Pole could shift to someplace else.

55 Iron within cooling molten rock orients itself to the poles before hardening. The ocean floor shows evidence of a changing magnetic field, and sea-floor spreading.

56 Pangea: The Super Continent All of the plates were once together.

57 Gondwondaland and Laurasia were two mega continents before Pangea.

58 What causes continental drift and plate tectonics?

59 Answer! Convection currents (Remember heat rises) move the plates

60 Plates spreading apart

61 Plates coming together

62 Converging Crust Spreading Crust Covection

63 New Area of Focus: Earth s Plate Boundaries.

64 Two types of Crust - -

65 Ocean Crust: More dense so it sinks more (Basalts).

66 Continental Crust: Less Dense so it floats higher (Granites)

67 Divergent Boundaries: Crust is created as two or more plates pull away from each other.

68 Draw a baseball in your journal, Please label the seam as the Mid-Atlantic Ridge that encircles the Earth. (Divergent Boundary)

69

70

71 Older Newer Newer Older 4 miles thick

72

73 Convergent Boundaries: Crust is destroyed and recycled back into the interior of the Earth. One plate dives under another.

74 Ocean vs. Continent (subduction zone)

75 Mountains / Volcanoes Trench Continental Crust Granites Lithosphere Lithosphere Asthenosphere

76

77

78 Ring of Fire: A zone of frequent earthquakes and volcanic eruptions that encircles the basin of the Pacific Ocean.

79 Volcanic Arch Island Chain / Archipelago Ocean Plate Ocean Plate

80 Ocean vs. Ocean Convergence

81 Archipelago: Group of volcanic islands formed from ocean crust convergence.

82 Continental Convergence: (Mountain Building).

83 Continent Divergence (Moving apart).

84