This document provides an overview of key concepts about the Earth and its movement. It begins by outlining the objectives of the chapter, which are to describe how the Earth's tilt, rotation, and revolution cause seasons; analyze how geological processes shape the Earth's surface; identify major landforms; and understand earthquakes, volcanoes, and the water cycle. It then provides details about the Earth's movement, including its daily rotation and annual revolution around the sun. It explains how this movement, combined with the planet's 23.5 degree tilt, results in the four seasons. The document also describes the structure of the Earth's interior layers and explains plate tectonics, including how the movement and collision of tectonic plates

1. The Earth
Chapter 2, Section 1

2. Section Objectives
• Describe how Earth’s tilt, rotation, and revolution
around the sun cause the four seasons.
• Analyze how processes deep within the Earth
affect its surface
• Identify major landforms and analyze how they
affect life on Earth
• Identify the causes of earthquakes and
volcanoes
• Understand the importance of water and the
hydrologic cycle.

3. A Tour Through the Rest of
the Solar System
Mercury Venus Earth Mars

5. The Solar System
• Our solar system = 8 planets (including Earth)
and many smaller bodies, all orbiting the sun

6. Disqualified: Poor Little Pluto!

7. Earth’s
Movement
Every planet rotates, or spins, on its axis
Axis: an imaginary line the runs through Earth’s
center between the North and South Poles
 It takes 24 hours to finish a complete spin on Earth’s
axis
24 hours = 1 day, or rotation
365 ¼ days = 1 year, or revolution
As Earth rotates, different parts of the planet are in
light or darkness

9. The Sun and
the Seasons
• Earth is tilted 23 ½° (degrees)
on its axis
• Seasons change as the Earth
orbits around the Sun
– When the Northern or Southern
Hemispheres receive DIRECT RAYS from the Sun,
they experience summer
– When those hemispheres receive INDIRECT
RAYS from the Sun, they experience winter
– This is why hemispheres have opposite seasons
• Winter in the Northern Hemisphere = summer in the
Southern Hemisphere!

11. PICK A SIDE!
•Which is your favorite
season?
–North Wall = Winter
–East Wall = Spring
–South Wall = Summer
–West Wall = Fall

12. The Sun and Seasons (cont.)

13. Solstices and Equinoxes
• Four days mark the beginning of the four
seasons:
– Summer Solstice (June 21)
• North Pole is tilted toward the Sun
• Sun is directly over Tropic of Cancer (23 1/2˚ N)
• Northern Hemisphere - longest day, shortest night
(opposite in Southern Hemisphere)
– Winter Solstice (December 22)
• North Pole is tilted away from the Sun
• Sun is directly over Tropic of Capricorn (23 1/2˚ S)
• Northern Hemisphere - shortest day, longest night
(opposite in Southern Hemisphere)
– Vernal (Spring) Equinox (around March 21) and
Autumnal (Fall) Equinox (around September 23)
• Day and night of equal length
• Sun shines directly over the Equator

15. QUICK CHECK!
•Indicate your answer by
raising your hand:
–1 = Winter
–2 = Spring
–3 = Summer
–4 = Fall

16. Inside the Earth
• Earth has three layers:
- Crust
- 31 to 62 miles deep
- Thickest under continents; thinner
below the oceans
- Mantle
- Layer of rock 1,800 miles thick!
- Outer mantle = sometimes melts,
creating magma, or melted rock
- Inner mantle = solid
- Outer Core
- Mostly liquid; molten iron and nickel
- 1,400 miles thick
- Inner Core
- Solid iron due to pressure from above!
- 700 miles thick; reaches 12,000°F

17. Tectonic Plates
• Earth’s crust is divided
into sections called
tectonic plates:
– The earth’s crust consists of
plates, or huge slabs of
rock, that move
– Plates float on top of liquid
rock just below the crust
– Plates often move in
different directions
– Oceans and continents sit
on top of these gigantic
plates!Iceland, where the North American
plate meets the European plate

18. Plate Tectonics Map

19. Pangea
• Scientists believe
that long ago all
the continents were
joined together in a
land mass called
Pangea
• However,
eventually, the
continents drifted
apart - this is called
“continental drift”
– Bill Nye: Pangea &
Plate Tectonics (Cut
at 2:00)

20. Pangea, cont.
• The plates are still moving today
– Plate under the Pacific moves west at 4”/year
– Plate along west edge of S. America moves east at
1.8”/year
• Some scientists believe that in another 250 million
years, the continents will be rejoined!

21. When Plates Meet
• Sometimes plates push against
each other, leading to one of
four things
– Plates smashing into each other =
mountain ranges, like the
Himalayas
– Thicker continent plate sliding over
a thinner ocean plate = volcanic
mountains, which erupt when
pressure between plates builds up
– Plates sliding alongside each other
= earthquakes along faults, or
cracks in the earth’s crust
– Plate movement along faults, like
the San Andreas Fault in California,
can produce damaging
earthquakes and tsunamis, or
underwater earthquakes.

22. The Ring of Fire
• The Ring of Fire is a circle
of volcanoes and
earthquakes along the
rim, or outer edge of the
Pacific Ocean.
• A large tectonic plate
under the ocean slides
against plates in the
surrounding continents.

23. Today’s Questions:
How does the movement of tectonic
plates impact landforms on earth?
What landforms are created?
How does this impact us,
the people who live on or
around these landforms?

24. Earthquakes & Tsunamis
– An earthquake is a violent shaking of the Earth’s crust
• Occur along faults, or cracks in the earth’s crust
• Happens often in the Ring of Fire, but also in other areas,
• Earthquakes beneath the ocean can produce tsunamis, or
large, powerful ocean waves which can cause great
destruction along the ocean coast.
• Earthquake Destruction (2:21)
• Killer Tsunamis (3:28) 2011 Japanese Tsunami Footage (5:39)
Earthquake Damage! Tsunami - November 2006!

25. Earthquake!
San Andreas Fault, CA, USA
China, 2008 - 8.0 Richter
Italy, 2009 - 6.3 Richter
Pakistan, 2005 - 7.6 Richter

26. Volcanoes
• A volcano is a mountain that erupts in an
explosion of molten rock, gases, and ash.
– Lava, which is molten rock, flows down the sides of
the mountain.
– The Ring of Fire contains more than 75% of the
world’s volcanoes.
– In spite of their destructive tendencies, volcanoes
can benefit, or be useful to, plants and animals by
making the soil richer
Volcano 101 (3:04)
Yellowstone Volcano (1:36)

27.  Landforms are physical
features on the Earth’s
surface.
 They are continually
reshaped by physical
processes
Landforms

28. Surface Landforms
 Mountain – a high,
steep elevation
 Hill – slopes upward,
but is lower and more
rounded
 Plain – a level area
 Plateau – a plain that
sits high above sea
level and usually has a
cliff on all sides

29. Ocean
Landforms
 Mountains, valleys, and
volcanoes also exist at
the bottom of the
ocean.
 Continental shelf – the
edge of a continent
that extends several
miles under the
ocean’s surface
 At the edge of the shelf,
the land slopes steeply
to the ocean floor
Diving along the Eurasian Continental Shelf!

30. Ocean Landforms, cont.
 Valleys under the
ocean are called
trenches
 Lowest spots in the
earth’s crust
 Mariana Trench =
deepest trench in the
world, located in the
west Pacific
Dive the Mariana
Trench! (:47)

31. Ocean Landforms, cont.
Computer imaging of Puerto
Rico Trench, Atlantic Ocean
Deep Sea - Exploring the
Zones (5:54)

32. The Changing Earth
• Changes in the earth
affect plant and animal
life
• Erosion: the process by
which rocks and soil
slowly break apart and
are swept away
• Weathering: when air,
water, wind, or ice
slowly wear away rocks
and soil
– Bill Nye: Erosion (Cut at
6:48ish)

33. Erosion and Weather at Work

34. Waters of the Earth
 Water flowing in rivers
is essential – or
necessary – for all
forms of life!
 About 70% of the
earth is water!
 Most of it is salt water,
which people can’t
drink

35. Fresh Water
 People use fresh
water to drink, cook,
and irrigate crops
 River – a path of
water that flows
from a higher
elevation to a lower
elevation
 Streams, brooks, and
creeks – like rivers,
only smaller
 Lake – a large body
of water surrounded
by land

36. Salt Water
 Salt water is a major
source of seafood
and a means of
transportation
 Oceans – large bodies of
Salt Water
 Currents – continuously
moving flows of water
– circulate through
oceans affect the
climates on land
 Seas – Smaller bodies
of salt water
 Ex. Red Sea

37. The Water Cycle
• Evaporation – The sun heats the ocean and
water vapor rises up into the atmosphere
• Condensation – Cooler temperatures in the
atmosphere cause the water vapor to
change into droplets that form clouds
• Precipitation -- Water droplets grow heavier
and fall back to Earth in the form of
precipitation, which is rain or snow
• Runoff (or Collection) – Precipitation soaks into
the ground and runs into rivers , underground
water reservoirs, and eventually, the ocean

39. Percentage of Water on Earth:
– 96.5% Oceans
– 1.7% Ground Water
– 1.8% Surface Water
– .024% Other Water
• (Ground ice, atmospheric water vapor,
marshes/wetlands, and in lorganisms
Of the amount of water on earth, only
2.5% is available for human use!
• Water Cycle Rap
• Thirstin's Water Cycle
• Soccer Game
• Stuck In Your Head Song

40. Landforms:
An Amazing Variety!

41. Escarpment
DEFINITION: A long, steep, cliff-like
ridge of land or rock, commonly
formed by faulting or fracturing of
the earth's crust

42. Terrace
DEFINITION: A leveled section of a
hilly cultivated area, designed to
slow or prevent rapid run-off of
irrigation water

43. Valley
DEFINITION: The
low area between
mountains or hills

44. Gully
DEFINITION:
Similar to a valley,
only smaller

45. Archipelago
DEFINITION: A
large group or
chain of islands

46. Coral Reef
DEFINITION: a reef or underwater ridge
composed mainly of coral and other organic
matter which has hardened into limestone.

47. Cove
DEFINITION: A
round indentation
or recess with a
narrow entrance,
located in the
shoreline of a sea,
lake, or river.

48. Headland
DEFINITION: An
area of land with
water on three sides
(large headlands are
called peninsulas).

49. Lagoon
DEFINITION: An area of salt
water separated from a larger
sea by a sandbank or coral reef

50. Cave
DEFINITION: A natural
underground opening in a
cliff or rock, big enough for a
person to enter.

51. Gorge & Canyon
Above: Royal Gorge, CO
Right: Grand Canyon
DEFINITION: A deep valley
with steep sides, formed
by streams carving
through plateaus. (A gorge
is a small canyon!)

52. Waterfall
DEFINITION: A flow of water that drops over
rocks, usually from a height of several feet.

53. Spring
Big Spring, Ozarks, MO (Largest spring in the U.S.!
Right: Grand Prismatic
Spring, Yellowstone
(160 degrees F!)
DEFINITION:
A place where
groundwater flows
out of the ground.

54. Crevasse
Gorner Glacier,
Zermatt, Switzerland
Easton Glacier,
Mount Baker, WA
Exploring bottom of
crevasse in Antarctica
DEFINITION:
A crack in a
glacier or
snow field.

55. Fjord Above: Fjords on coast of Greenland
(Bottom is largest fjord in the world!)
DEFINITION: A valley
with steep sides, which
is below sea level and
filled with salt water.

56. Mountain
DEFINITION: A natural elevation of
the earth's surface rising to a summit,
steeper and higher than a hill.

57. Cinder Cone
DEFINITION: A small,
cone-shaped volcano
built of ash and cinders.

58. Oceanic Trench
DEFINITION: A long narrow steep-sided
depression in the earth's crust under the
ocean.

59. Lava Dome
DEFINITION: A mound-shaped
growth resulting from the
eruption of lava in a volcano

60. Tea Table
DEFINITION: A rock
formation that has been
eroded away in the shape
of a table

61. Limestone Pavement
DEFINITION: Exposed limestone
rock that looks like artificial
pavement with cracks in it.

62. Hoodoo
DEFINITION:
A tall, thin
spire of rock
that sticks up
from the
bottom of an
dry drainage
basin or
badland.

63. Work Time Guidelines
 Planning sheets must be turned in with your project!
 Conserve supplies. We only have so much of everything
– take only what you need.
 Use paint carefully. IT STAINS! Put small amounts on
plates, and use cups for water to rinse your brushes.
Return brushes clean and toss plates at period’s end.
 Use computers and paint, etc. at separate tables!
 Play dough must be DRY before you paint it!
 If you need to store your landform, you may place it with
your name on it in Mr. Greenwald’s lab.
 BE CONSIDERATE! Be quiet if you are going into or
through other classrooms!
 You should be busy the ENTIRE TIME. If necessary, read or
work on other things while you wait for help.
 REMEMBER, this time is yours. Use it wisely!

64. Today’s Questions:
What makes a good project?
What makes a good presentation?
What makes a good
audience?

65. Presentation Expectations
 Have your project in front of you and be
ready to present when your name is called.
 Explain why you chose the project you did.
 Give the definition of at least one landform
present in your project.
 Share one thing that you are most proud of
about this project.
 Take your presentation seriously. Your
classmates want to learn from you!

66. Audience Expectations
 Give the presenter your full attention.
 Cause no distractions, either by talking or in
other ways (making faces, etc).
 Respect that presenting is a difficult task.
More people fear public speaking than
death. Be considerate of your classmates!
 Ask good questions. Be curious!
 Offer respectful applause – full, relatively
quick, and enthusiastic.

67. Any questions?