1. Unit 1 Notes
The Geosphere

2. Unit Objectives
EEn Explain how the sun produces energy which is transferred to the Earth by radiation.
EEn Explain how the rock cycle, plate tectonics, volcanoes, and earthquakes impact the lithosphere.
EEn Predict the locations of volcanoes, earthquakes, and faults based on information contained in a variety of maps.
EEn Explain how natural actions such as weathering, erosion (wind, water and gravity), and soil formation affect Earth’s surface.
EEn Explain the probability of and preparation for geohazards such as landslides, avalanches, earthquakes and volcanoes in a particular area based on available data
MAKE SURE NOTEBOOKS ARE SET-UP before starting!

3. EEn.1.1.3 How Stars Produce Energy

4. Combustion vs Burning
Burning is a type of combustion where flames can be seen
Most of the energy from burning is converted into light energy
Combustion is a reaction that takes place without flames so there is more energy in the form of heat produced

5. Nuclear Fission vs Nuclear Fusion
Nuclear Fission – nuclei split
Process used in nuclear power plants
Nuclear Fusion – nuclei combine
The way in which the Sun produces energy
These nuclear reactions are different than combustion.
Combustion = a chemical reaction where energy is released when one substance is changed into another. Wood turns into charcoal/ash when it burns.
Nuclear = a reaction on an atomic level where atoms are either split apart or fused together

6. Electromagnetic Spectrum
Most energy = smallest wavelength (have kids wave hand, short fast wave = gamma rays; slow, wide wave = radio waves)
Red Mice In Venice Usually eXit Gently

7. Filtering the EM Spectrum
Not every wavelength emitted by stars (including our Sun) reaches Earth’s surface
- Only the larger wavelengths of UV light, visible light, and smaller wavelengths of infrared and radio waves make it to Earth’s surface
- All other wavelengths are blocked at different heights in our atmosphere

8. Energy Transfer
Conduction – energy is transferred when particles touch each other
Convection – energy is transferred through fluids (liquids and gasses)
Radiation – energy is transferred by electromagnetic waves

9. Energy Transfer in Stars
Nuclei collide in the core releasing a photon
Photon energy is transferred from one particle to the next through conduction
Energy rises to the surface by convection
4. Energy is
then
radiated
out into
space

10. Solar Forces in Balance
Stars are held together by gravity.
Gravity tries to compress everything to the center.
Thermal and radiation pressure try to expand the star layers outward to infinity.

11. EEn.2.1.1 The Rock Cycle, Plate Tectonics, Volcanoes and Earthquakes

12. The Rock Cycle

13. Forces & Materials in the Rock Cycle
WEATHERING and EROSION
HEAT and PRESSURE
COMPACTION and CEMENTATION
MELTING and COOLING
Materials
IGNEOUS ROCK
SEDIMENTARY ROCK
METAMORPHIC ROCK
MAGMA/LAVA
SEDIMENTS

14. ROCK CYCLE

15. Energy is required for rocks to change from one type to the next
Sedimentary = external energy from the Sun to drive weathering and erosion
Igneous & Metamorphic = energy in the form of heat from the Earth’s core

16. Plate Tectonics

17. Earth’s Layers Crust is thin and rocky
Oceanic = younger rocks
Continental = older rocks
Mantle 82% of Earth’s volume is found here
Lithosphere – a strong layer under the upper mantle
Asthenosphere – a softer layer under the lithosphere
Core
Outer – liquid due to extreme heat
Inner – solid due to intense pressure
Compostion of layers due to density of materials;
heavier elements in the core
lightest elements in the crust

19. Continental Drift Pangaea!!!! Theory prior to plate tectonics
Proposed by German scientist Alfred Wegener in 1915
States that the continents had once been joined to form a single supercontinent
Pangaea!!!!
Pangaea = 240 million years ago
Pannotia = 600 million years ago
Rodinia = 1 billion years ago

20. Evidence The continental puzzle Matching fossils
Similar rock types and structures
Similar ancient climates

21. A New Theory
Wegener’s theory was replaced in the 1950s and 60s by plate tectonics
Takes in to account tectonic activity and mantle convection

22. Causes of Plate Tectonics
Mantle Convection
Transfer of thermal energy by the movement of heated matter in the mantle
Rising mantle – divergent boundary
Falling mantle- convergent boundary
Push and Pull
Ridge push
Slab pull

23. Earth’s Major Plates The lithosphere is divided into tectonic plates
These plates move and continually change shape and size

24. Types of Boundaries CONVERGENT DIVERGENT TRANSFORM
Where 2 tectonic plates are moving together
Creates a subduction zone
Trenches, island arcs and folded mountains
DIVERGENT
Where 2 tectonic plates are moving apart
Volcanism, earthquakes and high heat flow
TRANSFORM
Where 2 tectonic plates are sliding horizontally past one another
Long faults and shallow earthquakes

25. Convergent = Destroy
oceanic-continental
continental-continental
oceanic-oceanic
Form either a subduction zone or a continental collision
Earthquakes and volcanoes are common
Oceanic-Continental = Cascade Mountain Range
Continental-Continental = Himalayas
Oceanic-Oceanic = Mariana Trench, Japan, Aleutian
Islands

26. Divergent = Create Black Hills, SD East African Rift Valley Red Sea
Mid-Atlantic Ridge
Seafloor spreading

27. Transform = Conserve
San Andreas Fault in California most famous

28. Earthquakes

29. Earthquakes occur because of the forces of plate tectonics
Place where two tectonic plates meet form a boundary; faults are found at these boundaries
Earthquake waves can travel around the world through the different layers of the Earth
There are two parts – the focus and the epicenter

30. Two Parts of an Earthquake
Focus: Point within the Earth where the Earthquake starts.
Epicenter: On the surface above the epicenter.

31. Types of Faults
Reverse Fault/Thrust Fault = Convergent Boundary Normal Fault = Divergent Boundary Strike-Slip Fault = Transform Boundary

33. Two Types of Shocks Foreshock Aftershock Before an earthquake
Can happen years/days before an earthquake
Aftershock
Follows a major earthquake (usually smaller than original quake

34. How do we measure waves?
Seismograph

35. Two Types of Waves Body Waves Surface Wave
P wave: push/pull wave through rocks (1st)
S Wave: shake particles at right angles (2nd)
Surface Wave
Travel along the Earth’s surface

36. P and S Waves

37. Finding the Center of an Earthquake
Use measurements from three seismic stations
Data is used with a distance – time graph to triangulate the earthquake’s origin

38. Measuring Destructive Force
Magnitude (MMS)
amount of energy released at the focus
Intensity (Mercalli Scale)
Amount of shaking
Measured at a specific location
MMS = Moment magnitude scale which replaced the Richter scale in the 1970s

39. The Scales Richter Scale Mercalli Scale
Based on the amplitude (height) of the largest wave
Replaced by Moment Magnitude Scale (MMS)
Mercalli Scale
Amount of displacement from the fault

40. Types of Destruction
Seismic Vibrations Landslides Tsunamis Fires

41. Volcanoes

43. Factors Affecting Eruptions
Primary Factors
Magma composition
More silica = thicker lava
More iron/magnesium = thinner lava
Magma temperature
Amount of dissolved gases
Viscosity – a substance’s resistance to flow

44. Where Do Volcanoes Form?
Divergent boundaries
Magma chambers are close to the surface due to the plates moving apart
Convergent boundaries
Subducted plate melts and forms magma chambers under the volcano

45. Types of Volcanoes Shield Volcanoes Cinder Cones Composite Cones
Largest type
Form at divergent boundaries
Cinder Cones
Small cones of telphra
Form near shield volcanoes
Composite Cones
Made of alternating layers of lava and telphra
Form at convergent boundaries
Telphra = bits of rock or solidified lava dropped from the air after an explosive eruption

46. Other Volcanic Landforms
Calderas – a large depression in a volcano
Necks & Pipes – How magma gets through the volcano
Lava Plateaus

47. Mt. Saint Helens Eruption May 18, 1980

48. A Supervolcano?!?!?
Where could it be?

49. Yellowstone National Park Wyoming, United States

50. Een.2.1.2 Predicting Earthquakes and Volcanoes from Maps

51. Predicting Earthquakes
Short range – very difficult to determine exactly when and where an earthquake will happen, but seismographs give clues
Long range forecasts predict whether an earthquake is likely to occur in a given area within 30 to 100 years.

52. Because earthquakes and volcanoes occur at plate boundaries, areas along faults are most likely to experience these hazards

53. EEn2.1.3 Weathering, Erosion and Soil Formation

54. Mechanical vs Chemical Weathering
Occurs when physical forces break down rocks – temperature & pressure
Three process:
1.) Frost Wedging
2.) Unloading
3.) Biological Activity
Chemical
Transformation of a rock from one form to another
Water (hydrolysis), oxygen (oxidation), carbon dioxide (carbonic acid), acid rain
Water: A major factor!

55. Mechanical Weathering

56. Chemical Weathering

57. Rate of Weathering Three factors are:
1.) Rock Characteristics: the physical way a rock looks
2.) Climate: Temperature and moisture
3.) Differential Weathering: Different parts of rock mass weather at different rates.

58. Just a little soil information
An important product of weathering
Supports growth of plants
Four major components:
1.) Mineral Matter: about 45% of the matter in soil
2.) Organic Matter: 5% (decayed things)
3.) Water: 25% water
4.) Air: 25% air

59. How Soil is Formed Requires 5 things: Creates soil horizons
parent material, topography, climate, organisms, time
Creates soil horizons

60. Topography

61. Climate Cool, dry, sparse vegetation Warm, wet, abundant vegetation
Predominantly physical weathering
Warm, wet, abundant vegetation
Increased chemical weathering

62. The Soil Profile
Soil varies in texture, composition, structure, and color at different levels.
A Horizon – Topsoil
B Horizon – Subsoil
C Horizon – Bottom true to the parent material
R Horizon - Bedrock

63. Erosion Movement of weathered material from one location to another
Rates of Erosion:
More plants, grass, and trees helps to hold the soil in place.
Human activity that removes these things help to speed up erosion.

64. EEn2.1.4 Mass Movement and Geohazards

65. Mass Movement

66. What it is and its Triggers
The transfer of rock and soil down slope due to gravity and caused by weathering and erosion
Water
Saturating surfaces creating mudflows
Over-steepened Slopes
Water cuts under the bank of a river
Removal of Vegetation
Taking away plants and roots
Earthquakes
Shake loose soil creating a landslide

67. Types of Mass Movement
Based on the kind of material, how it moves and the speed of the movement.
Rockfall = rocks fall from a steep slope
Slides = land sides down suddenly
High mountain areas
Slumps = downward movement of a block of material in a curved surface
Creep = the slowest form of movement
Flows = mass amounts of movement
2 types:
Mudflow – Moves quickly
Earthflow – Moves slowly

70. Geohazards

71. Geohazards Landslides Mudslides Avalanches Falling rock Volcanoes
Earthquakes
Floods

72. Geohazard Protections
It is impossible to prevent geohazards or to know exactly where and when they will occur
Can use levees, damns, wire netting, breaks and special building codes to help limit damage and save lives
Having a disaster preparedness plan in place is extremely important for EVERYONE!
Mention Hurricane Hugo…

73. Geohazard Protection

75. Family Disaster Preparedness Plan Due September 18th
Unit 1 Project
Family Disaster Preparedness Plan
Due September 18th