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1

(Earth's Changing Surface Part 1 : Plate Tectonics)
What is the theory of continental drift? What information was Wegener lacking when he created his hypothesis?

- Wegener's Idea : continents "fit" together, geologic and fossil similarities, proposed idea of continental drift
- scientists rejected Wegener's idea because it did not contain enough evidence to support the theory
- Wegener failed to provide a suitable mechanism that could cause the continents to move, couldn't explain how continents moved
- continents plow through solid rock, no viable mechanism

2

(Earth's Changing Surface Part 1 : Plate Tectonics)
What is the role of convection currents in plate tectonics?

- circular currents in the mantle caused by the magma being heated by the core off the Earth
- they help to drive the movement of the rigid plates making up the earth's surface

3

(Earth's Changing Surface Part 2 : Plate Boundaries)
At which kind of plate boundary would you expect to see the following :
(A) rift valleys
(B) subduction
(C) lateral faults
(D) mid-ocean ridge
(E) volcanoes
(F) chains of volcanic islands
(G) very tall non-volcanic mountains

(A) rift valleys : divergent plate boundary
(B) subduction : convergent boundary
(C) lateral faults : transform boundary
(D) mid-ocean ridge : divergent boundary
(E) volcanoes : divergent and convergent boundary
(F) chains of volcanic islands : divergent boundary
(G) very tall non-volcanic mountains : continental continental convergent boundary

4

(Earth's Changing Surface Part 3 : Weathering and Erosion)
What is weathering?

- breakdown of rock into smaller pieces from exposure to wind, water, or biological forces

5

(Earth's Changing Surface Part 3 : Weathering and Erosion)
What is the difference between mechanical and chemical weathering?

- mechanical weathering : type of weathering in which rock is PHYSICALLY broken into smaller pieces
- chemical weathering : process that breaks down rock through CHEMICAL changes

6

(Earth's Changing Surface Part 3 : Weathering and Erosion)
Describe the following types of mechanical weathering. For each type, describe where these forces are likely to occur, what their action does to the rock, and what the resulting changes to the Earth's surface will be :
(A) frost wedging
(B) exfoliation
(C) thermal expansion
(D) crystal growth
(E) tree roots
(F) abrasion

(A) frost wedging :
- mechanical breakup of rock caused by expansion of freezing water in cracks and crevices
(B) exfoliation :
- rock that cracks into layers because of pressure release physical
(C) thermal expansion :
- as sea and ocean temps increase, water molecules near the surface move further apart, so that water volume increases and the sea level rises
- also daily heating and cooling of rocks do not seem to have an effect
- sudden exposure to high temperature though such as in forest fires or a grass fire may cause expansion and eventual breakage of rock
(D) crystal growth :
- salts from sea water can crystallize in pores
- cracks in rocks and the pressure exerted by the growing salt crystals can cause rocks to break apart
(E) tree roots :
- plant roots can extend into fractures and grow, causing expansion of fracture
- growth of plants can break rock
(F) abrasion :
- removing small pieces of rock over time by wind or water
- slowly the rock is just worn away, causes the rounding of angular pieces

7

(Earth's Changing Surface Part 3 : Weathering and Erosion)
Describe the following types of chemical weathering :
(A) dissolution
(B) oxidation
(C) hydrolysis

(A) dissolution :
- breaking minerals into ionic constituents
- all of the mineral is completely dissolved by water
(B) oxidation :
- chemical change in which a substance combines with oxygen, as when iron oxidizes, forming rust
(C) hydrolysis :
- breaking down complex molecules by the chemical addition of water
- H+ or OH- replaces an ion in the mineral

8

(Earth's Changing Surface Part 3 : Weathering and Erosion)
How does acid rain contribute to weathering?

- acid rain contributes to weathering by chemically breaking down minerals are in rocks and soil

9

(Earth's Changing Surface Part 3 : Weathering and Erosion)
What is erosion? How is it different than weathering?

- natural process; weathered particles are removed from rocks; transported by streams, glaciers, wind or other mobile agents; rock normally angular and jagged; particle size decreases and edges are rounded off

10

(Earth's Changing Surface Part 3 : Weathering and Erosion)
Explain the process of erosion due to gravity, surface water, ground water, wind, and glaciers. How do each of these create changes to Earth's surface?

(A) gravity :
- causes water and glaciers to move downhill and particles carried by wind and water to settle
- can also cause landslides and mudflows; surface water
(B) surface water :
- carries sediment water to other areas
(C) groundwater :
- process of chemical weathering causes much ground water erosion including the formation of caves and sinkholes
(D) wind :
- primarily known for smoothing and rounding landscapes as sand and dust carried by wind wear away rocks and land surface
(E) glaciers :
- when large bodies of ice pick up rocks and soil as they move; can destroy forests, carve out valleys, alter the course of rivers and wear down mountains
- the type of erosion that can cause hills and moraines

11

(Earth's Changing Surface Part 3 : Weathering and Erosion)
How do gravity and groundwater contribute to land subsidence?

- water is pulled down from glaciers, rain, etc, due to gravity and therefore holds nutrients

12

(Earth's Changing Surface Part 1 : Plate Tectonics)
What is the theory of plate tectonics? What evidence supports this theory?

- theory that pieces of the Earth's lithosphere are in constant motion, driven by convection currents in the mantle
- evidence :
- along sea floor spreading zones, the continents are separating from one another
- as they spread apart, magma comes to the surface and becomes new continental crust

13

(Earth's Changing Surface Part 4 : Convection)
What are convection currents? Draw a diagram of a convection current.

- SEE PAPER

14

(Earth's Changing Surface Part 1 : Plate Tectonics)
How did the discovery of sea floor spreading contribute to our understanding of plate tectonics?

- World War II required submarine navigators to know the topography of ocean floor
- Discovered contains wide variety of land forms
- sediment is not uniform on ocean floors
- new crust forms at new volcanic ridges
- mid ocean ridge : formation of new crust
- subduction zone : destruction of old crust
- magnetic stripping : further evidence for sea floor spreading and subduction, poles exchange places, youngest crust at mid ocean ridges and oldest crust at subduction zone

14

(Earth's Changing Surface Part 4 : Convection)
Explain how convection cells cause the following types of air movement in the atmosphere : local winds and Hadley cells

- local winds :
- winds that blow over short distances caused by unequal heating of Earth's surface within a small area
- uneven surface heating on small scale, air above warm surface rises and warms, rising air cools and sinks, air moved from high pressure to low pressure (wind)
- Hadley cells :
- a large-scale atmospheric convection cell in which air rises at the equator and sinks at medium latitudes, about 30 degrees north or south (aides in creating the trade winds), uneven surface heating on global scale, transports heat from Equator to poles, produces global pressure systems

15

(Atmosphere Part 1 : Components of Earth's Atmosphere)
List the layers of Earth's atmosphere from surface to space

- troposphere :
- weather occurs
- lowest and thinnest layer
- most gases of atmosphere
- stratosphere :
- ozone layer
- temperature increases because of ozone absorption of UV rays
- mesosphere :
- middle, cold
- thermosphere :
- gets warmer
- no well defined upper limit
- absorbs much of the X-ray and UV radiation
- exosphere :
- exit, interface between Earth and space
- beyond 500 km, atoms and molecules can escape to space.

16

(Atmosphere Part 1 : Components of Earth's Atmosphere)
What is the ionosphere?

- an area of the atmosphere containing positively charged particles called ions (Aurora Borealis or Northern Lights) and found in the upper mesosphere and lower thermosphere
- not a true layer

17

(Atmosphere Part 1 : Components of Earth's Atmosphere)
What components of the atmosphere are in fixed amounts? List them from most to least plentiful.

- nitrogen, oxygen, argon, neon, helium, methane, hydrogen

18

(Atmosphere Part 1 : Components of Earth's Atmosphere)
What components of the atmosphere are in variable amounts?

- water vapor, carbon dioxide, ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, particles (pollen, dust)

19

(Atmosphere Part 1 : Components of Earth's Atmosphere)
What role does carbon dioxide play in the atmosphere?

- humidity : is the mass of water vapor a given volume of air contains; plays a role in weather
- carbon dioxide
- plant life : keeps plants alive
- greenhouse effect

20

(Atmosphere Part 2 : Air Masses and Fronts)
Describe the different types of air masses.

- maritime arctic : cool, moist, unstable :
- Arctic
- continental arctic : cool, dry, stable :
- Greenland
- maritime polar : cool, moist, unstable :
- North Atlantic, Pacific Ocean
- continental polar : cold, dry, stable : Alaska, Canada
- maritime tropical : warm, moist, usually unstable :
- Caribbean Sea, Gulf of Mexico
- continental tropical : hot, dry, stable aloft, unstable at surface
- Mexico, Southwestern U.S.

21

(Atmosphere Part 2 : Air Masses and Fronts)
Explain the difference in how the air masses are moving in a cold front versus a warm front.

- cold front : cold air mass on the move, cold air sinks, forces warm air to lift above cold air
- warm front : warm air mass rises

22

(Atmosphere Part 2 : Air Masses and Fronts)
What happens to the weather when a cold front moves into the area?

- cold air moves under warm air which is less dense and pushes air up (produces thunderstorms, heavy rain, or snow)

23

(Atmosphere Part 2 : Air Masses and Fronts)
What happens to the weather when a warm front moves into an area? How is this different than a cold front?

- warm air moves over cold air and brings drizzly rain or light snow and then are followed by warm and clear weather
- less dense, warmer air mass flows upward over more dense cooler air, frontal lifting

24

(Atmosphere Part 2 : Air Masses and Fronts)
airmass

- a volume of air that has a characteristic temperature and humidity throughout.
- tends to remain intact as it travels
- acquires temperature and moisture characteristics of its source region

25

(Atmosphere Part 2 : Air Masses and Fronts)
front

- associated with rapid changes
- boundary where air masses meet

26

(Atmosphere Part 3 : Coriolis Effect and Storms)
What is the cause of the Coriolis effect?

- causes moving air and water to turn left in the Southern Hemisphere and turn right in the Northern Hemisphere due to Earth's rotation
- deflection of wind varies according to speed and latitude : faster wind, greater direction; deflection greatest at poles, decreases to zero at equator

27

(Atmosphere Part 3 : Coriolis Effect and Storms)
Give an example of the Coriolis effect.

- hurricane formation :
- do not form at equator
- if in northern hemisphere the winds will flow counterclockwise
- air travel :
- flight path that might look arrow straight on a flat map actually appears curved on a globe

28

(Atmosphere Part 3 : Coriolis Effect and Storms)
What affect does the Coriolis effect have on rotation in storms?

- in the Northern Hemisphere, storms will rotate counterclockwise
- in the Southern Hemisphere, storms will rotate clockwise

29

(Atmosphere Part 3 : Coriolis Effect and Storms)
Describe the changes in weather associated with a low-pressure center (cyclone) and a high-pressure system (anticyclone)

- low-pressure center (cyclone) :
- usually associated with wetter, warmer and lousy weather; ascending air, horizontal winds, counterclockwise rotation, cyclonic rotation
- high-pressure center (anticyclone) :
- high pressure are created by sinking cold air