EAPS 106, Geosciences in the Cinema
Exam 1 Study Guide
From the lectures you should know the following:
Unit 1 – Plate Tectonics
1. What a solar nebula is:
● Disc of gas and dust surrounding all new stars
2. Why new planets are hot inside
● Planet accretion results from lots of collisions, each producing heat.
● Stopping a moving object converts motion to heat.
● Combined with heat from decaying radioactive elements, interiors of all new planets are
hot inside.
3. What a rogue planet is
● One that does not orbit a star.
4. Why the interior of the Earth is layered and what those layers are
● Internal structure is differentiated
● Separation of metals and rocks because of density differences
● Differentiation
● Crust, mantle, outer core, inner core
5. Why the inner core is solid despite it being hotter than the outer core
● Outer core is still liquid because it’s the only layer that remains hotter than its melting
temperature
● Inner core is cooler than its personal melting temperature
○ Greater pressure deeper in earth causes the melting temperature to be higher
6. The meanings of lithosphere, asthenosphere, and plate tectonics
● Lithosphere: Strong outer shell of the earth consisting of the cold crust and cold
uppermost mantle
● Asthenosphere: Mantle weakened by high temperatures that underlies the lithosphere that
flows like a fluid
● Lithosphere broken into (13) plates, and their subsequent motion is plate tectonics
○ Fluidity of the asthenosphere enables the lithosphere to move around
7. Why mantle beneath the asthenosphere does not flow easily
● Mantle below the asthenosphere does not flow as easily because of higher pressures at
depth.
8. The evidence for continental drift and why scientists of Wegener’s time did not accept it
● North and South American coastlines fit with Europe and Africa
● Identical Volcanic Rocks on both sides of Atlantic
● Fossils of non swimmers found on both sides of modern oceans.
● Disbelieved because nobody knew what force could be strong enough to make the
continents move
○ It would cause strong oceanic crust to get out of the way
9. What a magnetic reversal is and how we know it has reverses
, ● Magnetic reversal is when north and south switch places.
● Timing is known by dating the age of lava flows.
○ Magnetic crystals in volcanic rock act like little compasses
10. The breakthrough observation that led to the theory of plate tectonics
● Magnetic reversals revealed the age of ocean crust, and saw it spreading away from
spreading centers.
● Led to the theory of plate tectonics by showing that all the earth’s crust was mobile.
11. What mid-ocean ridges are and the relative age of oceanic and continental crust
● Mid ocean ridges are spreading centers where new ocean crust forms then spreads out
● Mid atlantic ridge has been spreading new crust for 180 million years
● Oceans are relatively young (<200 million) continents are (>1 billion) years old
12. Understand subduction zones and the processes they lead to
● Crust must be destroyed to account for growth, subduction zones are where ocean plates
dive back into earth’s interior
● Give rise to high mountains, deep trenches, volcanoes and large earthquakes
13. Understand transform plate boundary that the San Andreas Fault is one
● Tectonic plates that slide past each other on the surface of the earth.
● San Andreas Fault is a transform plate boundary between the pacific and NA plates.
15. Understand what is meant by a passive margin
● Not all boundaries between continental and oceanic crust are plate boundaries.
● These are referred to as passive margins because there is no relative motion
○ No earthquakes or volcanoes
● Passive margins are locations where super continents originally broke up.
15. Whether Hawaii lies on a plate boundary
● Hawaii does not lie on a plate boundary.
16. How earthquakes are triggered
● Triggered when very slight stress increases push an already highly stressed fault passed a
threshold
17. What a supercontinent is
● Collections of many continents
18. How plate tectonics may have influenced the evolution of whales and dolphins
● Ties to shallowing of the Tethys Sea when India first collided into Asia
19. How conduction, convection, and radiation transfer heat
● Convection: Heat transfer through fluid motions of liquids and gasses, as well as solids
that flow like a fluid.
● Conduction: Heat transfer through a solid through the spread of vibrations on the atomic
scale.
● Radiation: Heat transfer through electromagnetic waves (light) through a transparent
medium
20. That a solid, crystalline material can convect
● When it acts as a fluid. Think silly putty.
21. What drives plate tectonics
● Arises from the process that serves to remove heat from Earth’s deep interior.
Exam 1 Study Guide
From the lectures you should know the following:
Unit 1 – Plate Tectonics
1. What a solar nebula is:
● Disc of gas and dust surrounding all new stars
2. Why new planets are hot inside
● Planet accretion results from lots of collisions, each producing heat.
● Stopping a moving object converts motion to heat.
● Combined with heat from decaying radioactive elements, interiors of all new planets are
hot inside.
3. What a rogue planet is
● One that does not orbit a star.
4. Why the interior of the Earth is layered and what those layers are
● Internal structure is differentiated
● Separation of metals and rocks because of density differences
● Differentiation
● Crust, mantle, outer core, inner core
5. Why the inner core is solid despite it being hotter than the outer core
● Outer core is still liquid because it’s the only layer that remains hotter than its melting
temperature
● Inner core is cooler than its personal melting temperature
○ Greater pressure deeper in earth causes the melting temperature to be higher
6. The meanings of lithosphere, asthenosphere, and plate tectonics
● Lithosphere: Strong outer shell of the earth consisting of the cold crust and cold
uppermost mantle
● Asthenosphere: Mantle weakened by high temperatures that underlies the lithosphere that
flows like a fluid
● Lithosphere broken into (13) plates, and their subsequent motion is plate tectonics
○ Fluidity of the asthenosphere enables the lithosphere to move around
7. Why mantle beneath the asthenosphere does not flow easily
● Mantle below the asthenosphere does not flow as easily because of higher pressures at
depth.
8. The evidence for continental drift and why scientists of Wegener’s time did not accept it
● North and South American coastlines fit with Europe and Africa
● Identical Volcanic Rocks on both sides of Atlantic
● Fossils of non swimmers found on both sides of modern oceans.
● Disbelieved because nobody knew what force could be strong enough to make the
continents move
○ It would cause strong oceanic crust to get out of the way
9. What a magnetic reversal is and how we know it has reverses
, ● Magnetic reversal is when north and south switch places.
● Timing is known by dating the age of lava flows.
○ Magnetic crystals in volcanic rock act like little compasses
10. The breakthrough observation that led to the theory of plate tectonics
● Magnetic reversals revealed the age of ocean crust, and saw it spreading away from
spreading centers.
● Led to the theory of plate tectonics by showing that all the earth’s crust was mobile.
11. What mid-ocean ridges are and the relative age of oceanic and continental crust
● Mid ocean ridges are spreading centers where new ocean crust forms then spreads out
● Mid atlantic ridge has been spreading new crust for 180 million years
● Oceans are relatively young (<200 million) continents are (>1 billion) years old
12. Understand subduction zones and the processes they lead to
● Crust must be destroyed to account for growth, subduction zones are where ocean plates
dive back into earth’s interior
● Give rise to high mountains, deep trenches, volcanoes and large earthquakes
13. Understand transform plate boundary that the San Andreas Fault is one
● Tectonic plates that slide past each other on the surface of the earth.
● San Andreas Fault is a transform plate boundary between the pacific and NA plates.
15. Understand what is meant by a passive margin
● Not all boundaries between continental and oceanic crust are plate boundaries.
● These are referred to as passive margins because there is no relative motion
○ No earthquakes or volcanoes
● Passive margins are locations where super continents originally broke up.
15. Whether Hawaii lies on a plate boundary
● Hawaii does not lie on a plate boundary.
16. How earthquakes are triggered
● Triggered when very slight stress increases push an already highly stressed fault passed a
threshold
17. What a supercontinent is
● Collections of many continents
18. How plate tectonics may have influenced the evolution of whales and dolphins
● Ties to shallowing of the Tethys Sea when India first collided into Asia
19. How conduction, convection, and radiation transfer heat
● Convection: Heat transfer through fluid motions of liquids and gasses, as well as solids
that flow like a fluid.
● Conduction: Heat transfer through a solid through the spread of vibrations on the atomic
scale.
● Radiation: Heat transfer through electromagnetic waves (light) through a transparent
medium
20. That a solid, crystalline material can convect
● When it acts as a fluid. Think silly putty.
21. What drives plate tectonics
● Arises from the process that serves to remove heat from Earth’s deep interior.
