Presentation is loading. Please wait.

Presentation is loading. Please wait.

Formation of Planets Accretion of dust in space due to GRAVITATIONAL FORCES –Dust –Asteroids –Planets 1.accretion of Heavy elements 2.attraction of Light.

Similar presentations


Presentation on theme: "Formation of Planets Accretion of dust in space due to GRAVITATIONAL FORCES –Dust –Asteroids –Planets 1.accretion of Heavy elements 2.attraction of Light."— Presentation transcript:

1 Formation of Planets Accretion of dust in space due to GRAVITATIONAL FORCES –Dust –Asteroids –Planets 1.accretion of Heavy elements 2.attraction of Light gases to dense nucleus

2 Origin Solar System

3 Recent planets were HOT –Compressional Heating –Impact Heating –Radioactive Decay The Earth is layered by Densities –Densest Core –Lightest Crust Formation of Planets

4

5 Core (Fe, Ni) –Inner Core (solid) –Outer Core (liquid) Mantle (plastic) – very close to melting point –Inner Mantle –Asthenosphere Lithosphere (rigid) –Upper Mantle (~100km) (Lithosphere) –Crust Oceanic Continental Earth’s Layers

6 Earth’s Core, Mantle and Crust

7 Ocean Floor and Margins

8 If the entire history of the earth were 1 year long: * Origin of Earth 4600 MY Oceans first form 4000 MY Oldest dated rocks 3800 MY First life form 3600 MY Ocean – Atmosphere equilibrium 1000 MY Beginning of well known Geology 600 MY Multicelular complex organisms 700 MY First FISH! 510 MY First Land Plants 430 MY

9 Dinosaurs evolve Dinosaurs extinct DECEMBER *

10 December 31 st 9:15 pm Homo sapiens evolves Historical Times = 1 minute 18 sec. Columbus discovers America = 3 sec. till midnight HMS Challenger Expedition = 0.9 sec. till midnight You have been around for ~0.13 seconds

11 Asthenosphere & Lithosphere

12 Crust Oceanic Crust –Density: ~2.9 g/m 3 –Mineral composition: Basalt (Fe, Mg, SiO 2 ) –Thickness: ~5-10 km –Elevation: ~ 3800m below sea level –Age: <200 MY Continental Crust –Density: ~2.75 g/m 3 –Mineral Composition: Granite (Na, K, SiO 2 ) –Thickness: ~20-90 km –Elevation: ~840m above sea level –Age: <3800 MY

13 Lithosphere

14 Study of Earth’s Interior Rock Sampling & Drilling Meteorites Seismic Studies

15 Rock Drilling ODP (Ocean Drilling Program)

16 Meteorites

17 Seismic Studies

18

19 Seismic Studies Differential speed of seismic/sound waves due to density differences –Pressure Waves (p) Parallel to direction of motion Travel through liquids –Shear Waves (s) Perpendicular to direction of motion DO NOT travel through liquids Seismic waves refract & reflect at density boundaries

20 Seismic Waves

21

22 Convection Processes Shallow and deep mantle convection cells

23 Convection Processes

24 Divergent Margins - Ridges New oceanic crust formation Spreading

25 Convergent Margins - Trenches Oceanic crust Destruction Convergence & Subduction

26 Lithosphere Plates

27 Earthquakes Shallow (0-70 km) Medium ( km) Deep (>300 km)

28 250 – 225 MY

29 Spreading Cycles

30 Hot Spot

31

32

33 Loihi Volcano

34

35 Evolution of Coral Reefs Fringe reefs Barrier reefs Atolls

36

37 Hot Spot Map

38 Convergent Margins Continental Convergent Margins –Oceanic crust / Continental crust –Pacific Coast South America Oceanic Convergent Margins –Oceanic crust / Oceanic crust –Aleutian Trench, Caribbean Arch Continental Collision Margins –Continental crust / Continental crust –Himalaya mountains

39 Continental Convergent Margins Oceanic Convergent Margins Continental Collision Margins

40 Continental Convergent Margins Andes Mountains

41 Oceanic Convergent Margins Caribbean Island Arch

42 Convergent margin vulcanism St Helens

43 Convergent margin vulcanism Soufriere - Montserrat

44 Continental Collision Margin Himalaya Mountains

45

46

47 Divergent Margins Oceanic Divergent Margins –Two spreading plates, upwelling magma –Central Rift Valley and Oceanic Ridge –Mid Atlantic Ridge (Slow 1-5 cm/year) –East Pacific Rise (Fast 9-18 cm/year) Continental Divergent Margins –Crustal upwarp, Rift Valley, Linear Ocean –East African Ridge, Red Sea

48

49 Continental Divergent Margins African Rift Valley

50

51 Mid Atlantic Ridge

52 Mid Atlantic Ridge

53 Mid Atlantic Ridge http

54 East Pacific Rise

55 East Pacific Rise

56 East Pacific Rise

57 Divergent margin vulcanism

58

59 Ocean Crust Age

60 Convection Processes Shallow and deep mantle convection cells

61 Passive Continental Margins

62 Figure 2.28

63

64 Transform Faults Two plates slide by each other Numerous earthquakes along faults Common in divergent and convergent margins

65 Transform Fault

66

67 Mid Atlantic Ridge

68

69 San Andreas Fault between Pacific & N. American plates

70

71

72

73 Plate Tectonics History Alfred Wegener (1915) –Continental Drift Theory –Panagea ( MY)

74 Plate Tectonics History Alfred Hess (1960) –Seafloor spreading theory –Geo-Poetry WHAT DATA PROVES PLATE TECTONICS?

75 Figure 2.17

76 Magnetic Anomaly

77 Reversal Earth’s Magnetic Polarity

78 Sediment Thickness

79 Ocean Sediment Drilling ODP (Ocean Drilling Program)

80 Age Difference Ocean Crust: <200 MY Continental Crust: <3800 MY

81 Earth Quake Distribution

82 Earthquakes Shallow (<100km) Deep (>100km)

83 Continent Fitting

84 Paleomagnetism

85 Direct Movement Measurements


Download ppt "Formation of Planets Accretion of dust in space due to GRAVITATIONAL FORCES –Dust –Asteroids –Planets 1.accretion of Heavy elements 2.attraction of Light."

Similar presentations


Ads by Google