Card Set Information
FSU Burnett Unit
OCE1001 Flashcards to study for exam 1 FSU
1. Has the chemical composition of ocean water remained constant through geologic time?
No b/c acidity of rain broke down minerals which mixed into ocean water
2. Could the earth’s mantle have produced enough water to fill the oceans?
No, outgassing was not enough, ice comets also contributed.
3. What do we call organisms that can make their own food from inorganic carbon sources?
4. What do we call organisms that can break down organic molecules produced by other organisms to release energy?
5. Why did the separation of the Earth into layers occur?
b/c of plate tectonics
6. What gases did the earth’s early atmosphere (from outgassing) include?
amonia, carbon dioxide, hydrogen, methane
7. How can we use natural radioactive isotopes to determine the age of earth materials?
Comparing the amount of radioactive material and the amount of decay in rocks
8. What do we call lines on the earth’s grid system that run parallel to each other in an east-west direction and measure locations north or south?
Lines of latitude
9. What is a simple and reliable way to measure latitude?
The Sun or the North Star
10. Where is the deepest spot in the world’s ocean?
11. What are manganese nodules?
Rock concentrations found on the seafloor containing rare minerals like nickel, cobalt, and copper
12. What are gas hydrates?
Ice formations of CH4 and H2O. Potential source of NRG in future
13. Who was the 1st European explorer to circumnavigate the earth?
14. Is population growth linear or exponential?
What is the “Rule of 70” for estimating population growth?
70 divided by the doubling time = number of years until population doubles
15. What countries have some of the fastest growing populations in the world?
Developing countries (Nigeria, Ethiopia).
Are some countries losing population?
Developed countries (Japan).
16. There are 17 “megacities” (greater than 10 million population) in the world today. Most of them (11) are in what region of the world?
17. What city has the highest population in the world at around 30 million?
18. What are some mineral resources that are currently exploited from the sea bed? What mineral resources may be a future resource?
Petroleum, sand, gravel, salt
19. What is the “Exclusive Economic Zone?”
coastal zone of 200 nautical miles which the U.S. claims ownership of minerals and resources in oceans around our territories
20. The world fish catch seems to have leveled off at around 80-90 million tons annually in spite of the fact that we have better technology and more ships involved in fishing. Why has this happened?
Overfishing, shark-fining, and trophy fishing
1. True/False: The Earth's climate system involves the exchange of heat and water among the atmosphere, hydrosphere, geosphere, biosphere, and cryosphere.
2. True/False: Feedback loops are the interactions among the Earth's five spheres that either reinforce or negate changes in climate.
3. True/False: There is a significant positive correlation with sunspot activity and mean global temperature.
4. True/False: Volcanic eruptions have no impact on global climate patterns, they only affect local climate.
5. True/False: Decrease of summer ice cover in the Arctic Ocean has had a significant impact on Arctic wildlife.
6. The zone in the ocean where sound can travel extremely long distances is called ____.
7. The atmospheric component that contributes to the majority of greenhouse warming on Earth is ___.
8. Natural causes for global climate change include which processes?
Movements of Earth’s Plates, orbital variations, solar energy changes (minimal), volcanic eruptions
9. Which atmospheric constituent has the greatest ability to absorb heat (on a per molecule basis)?
10. An agreement amongst 60 nations to voluntarily limit greenhouse gas emissions is called the _____ Protocol.
11. Sea level rise worldwide can be attributed to what factors?
12. A reduction in the strength of the North Atlantic Current and a decrease in North Atlantic bottom water formation would most likely result in what climatic effect in Europe?
13. List the five parts of the Earth’s climate system.
14. What are climate feedback loops?
15. When we talk about past climates we mention “proxy data” – what do we mean by that?
16. Why has the carbon dioxide level of the atmosphere been rising for more than 150 years?
17. Describe several changes that are already occurring in the oceans because of global warming.
18. What is the ocean’s “biological pump” and how does it help reduce global warming?
19. What is the “iron hypothesis”?
20. What’s the difference between “weather” and “climate”?
Weather is day to day. Climate is over long time
21. What causes the annual up and down cycles in CO2 concentration in the atmosphere?
1. What characteristic of the seafloor supports the idea that subduction must take place?
Symmetric pattern of ocean floor ages
2. What is the relationship between the magnetic north pole and the geographic north pole?
because the magnetic north pole is constantly changing
3. New crust is formed at ___________ (ocean-floor feature) and old crust is subducted at _________ (ocean-floor feature).
Mid-oceanic ranges, convergent plate boundaries
4. Do you find older seafloor rocks at mid-ocean ridges or in trenches?
5. What type of plate boundary has the most earthquakes?
6. Are deep-focus earthquakes more common in trenches or along mid-ocean ridges?
7. Does the magnetic field of the Earth reverse itself each time magma erupts at a mid-ocean ridge?
8. Give an example of a fast-moving spreading ridge and a slow-moving ridge. Which one tends to be more gently sloped than the other?
East Pacific Rise is fast moving. Mid-Atlantic Ridge is slow moving.
9. Are deep-sea trenches found at convergent or divergent plate boundaries?
10. Are the earthquakes at divergent plate boundaries shallow or deep focus?
11. How can fossils found in marine sediments provide evidence concerning plate tectonics?
Dating fossils can show age of separation
12. All continents fit together with the least number of overlaps and gaps when the continents are matched along what depth contour?
2,000 meters below sea level
13. How is it that fossils of ancient polar plants are currently found near the equator?
B/c all the continents used to fit together on Pangaea
14. Is the climate distribution on Earth primarily controlled by latitude or longitude?
15. Provide four pieces of evidence that supported continental drift.
1. Fit of continents 2. Matching sequence of rocks and mountains 3. Glacial ages and other climatic evidence 4. Distribution of organisms
16. What was the principal line of evidence that confirmed continental drift?
Pattern of alternate reversals of the earth’s magnetic field
17. The scientists Vine and Matthews determined that new ocean floor was being produced at ocean ridges by examining what evidence from the sea floor?
The unrelated pattern of magnetic sea floor stripes with the process of sea floor spreading
18. What is the relationship between the age of the sea floor and seafloor spreading?
If spreading does occur, youngest sea floor would be atop the mid-oceanic ridge and would become older on either side in a symmetric pattern
19. Describe the seafloor magnetic pattern that is found around mid-ocean ridges.
20. Why do oceans become deeper moving away from the mid-ocean ridges?
There are mountain ranges near the center of mid-ocean ridges and they become extremely deep trenches at the end of ocean basins
21. How do we explain the differences in height (thickness) between continental crust and oceanic crust?
Oceanic crust – mass of rock with basaltic composition (5 km thick), continental crust – composed of ingneous rock and granite (35-60 km thick)
22. What is the “asthenosphere?”
layer of earth that lies just below lithosphere in upper mantle, which is involved in plate movements and isostatic adjustments
23. What is the “lithosphere?”
outer layer of earth’s structure includes the crust and upper mantle, major component in plate tectonic movement
24. Is there any change in the thickness of the lithosphere as one moves from the oceanic ridge towards an oceanic trench?
25. What is the relationship between deep ocean trenches and subduction zones?
Deep ocean trenches are the beginning of subduction zones
26. What is a “hot spot?”
area of intense volcanic action, unrelated to plate boundaries
27. Is the Mid-Atlantic Ridge an example of a divergent or convergent plate boundary?
29. What type of plate boundary are volcanic island arcs associated?
30. Along what type of plate boundary would you expect to find andesitic volcanoes?
Oceanic-continental convergent boundary
31. Assume the width of the North Atlanta Ocean Basin is 9600 km. If the half spreading rate of the Mid-Atlantic Ridge is 4 cm/yr, how long did it take for the ocean basin to form?
32. Based on your estimates of distances from the hotspot and the ages of the Hawaiian Islands shown on Figure 2.25, calculate the rate of movement of the Pacific Plate.
1. Are abyssal plains more extensive on the floor of the Atlantic or on the floor of the Pacific?
2. A sediment-laden current that flows off of the continental shelf is called a ______ current.
3. What are submarine canyons?
Canyons found on the seafloor
4. Do hydrothermal vents have a significant impact on ocean chemistry?
5. What do the two relatively flat areas on the hypsographic curve represent:
6. What method is most frequently used to investigate sediment and rock layers of the sea floor?
Multi-beam echo sounding and side scan sonar
7. What are the characteristics of passive continental margins?
Low tectonic activity
8. What are the characteristics of active continental margins?
high degree of tectonic activity
9. Give the correct order of marine provinces from the coast out to the mid-ocean ridge.
Continental Margin, Ocean Basin Floor, Mid-Ocean Ridge
10. What is the continental slope?
Lies beneath the shelf and is where deep ocean basins begin
Generally flat zone extending from beneath the ocean surface to a point at which a marked increase in slope angle occurs
11. What provinces make up “continental margins”?
12. How did submarine canyons form?
Turbidity currents moved downwards
13. Where are the steepest slopes in the ocean found? Deep ocean trenches
14. What is an abyssal plain?
A flat depositional surface extending seaward from the continental rise or oceanic trench
16. Where is old lithosphere destroyed?
Convergent plate boundaries
17. Where does new lithosphere form in the ocean?
18. Describe the direction of motion along a seafloor transform fault.
One plate slides horizontally past another
19. Are transform faults perpendicular or parallel to the axes of mid-ocean ridges?