Download Oceanography Review for Final

 Name__________ANSWER KEY___________ Oceanography Review for Final 1. Structure of the Earth 1.1.
Origin of the Earth 1.
How old is the universe thought to be? 13.7 billion years 2.
How old is the Earth thought to be? 4.5 billion years 1.2.
Layers of the Earth 3.
Draw and label the layers of the Earth. Keep the scale of the layers. crust
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outer core inner core What states of matter (solid/liquid/gas) are each of the layers of the Earth? The crust is solid, the mantle is a very thick liquid, outer core is liquid, inner core is solid. 5.
What three physical properties increase as you go deeper in the Earth? temperature, pressure, density 6.
What two things do scientists study in order to determine the interior structure of Earth? earthquake waves and the Earth’s magnetic field 7.
What is oceanic crust made of? basalt 8.
What is continental crust made of? granite 9.
Which is more dense – continental crust or oceanic crust? Which is thicker? Oceanic crust is more dense; Continental crust is thicker 10. What is the Earth’s core made of? iron and nickel 11. Why is the Earth’s inner core solid rather than liquid? because of the immense pressure at the center of the Earth 2. Our Dynamic Earth 2.1. Plate Tectonics 12. Who is credited with coming up with the original idea of continental drift? German scientist Alfred Wegener 13. What pieces of evidence support the theory of continental drift? How does each support the theory? 1) Fit of continents like a puzzle – the continents look like they were once one big continent; 2) Rock type and structural similarities – rocks and mountain ranges formed together, and then the continents separated; 3) Fossil evidence – plants and animals 4.
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which are not suited to cross oceans are found on shores across the ocean from each other, showing that perhaps the plants and animals evolved together on one land mass, and then the land separated; 4) Paleoclimatic evidence – similar glacial deposits and grooves carved by glaciers were found across the ocean from each other implying that the land was probably together at some point; 5) Paleomagnetism – magnetic properties of rocks indicates that at some point the land was together and separated. Who revised the theory of continental drift by explaining plate tectonics? Harry Hess (Princeton University) What is the difference between the theory of continental drift and the theory of plate tectonics? Continental drift says that the continents float around the world, while plate tectonics says that the continents are on tectonic plates which move and interact with one another. Plate tectonics gives a mechanism for continental drift. What is Pangaea? One large supercontinent, about 200 million years ago What has happened to the continents in the last 200 million years? Pangaea started to break apart and have been moving at the rate of the growth of a fingernail, 2‐10cm per year Name the seven major tectonic plates. (There are many more though.) North American, South American, Eurasian, African, Antarctic, Australian‐Indian, Pacific Name the major plate boundary types. What is happening at each boundary? What types of plates are involved in each boundary? What geographic features are typical for each type of boundary? Name a specific example of each boundary. Boundary Description Plates Features Example 2 oceanic or Mountains Himalayas Convergent Two plates And Japan (collisional) moving towards 2 continental or islands each other Oceanic and Volcanoes and Andes Convergent Plates moving continental trenches Mountains and (subduction) towards each Peru‐Chile other and one Trench sinks underneath Divergent Plates are Usually 2 Mid‐ocean Mid‐Atlantic separating oceanic ridge Ridge Transform Plates sliding Usually 2 Fault and San Andreas past each other continental earthquakes Fault What mechanism inside the earth aids in moving plates? In what layer? convection currents in the mantle What is the most important source of energy for plate tectonics? heat energy from the interior of the earth What is seafloor spreading? the process of plates diverging at the bottom of the ocean, forming new oceanic crust at the mid‐ocean ridge Is the Atlantic Ocean getting bigger? If so, why is the Earth as a whole not getting bigger? yes, because of a divergent plate boundary at the Mid‐Atlantic Ridge, the Atlantic Ocean is constantly growing, but the whole Earth is not getting bigger because the Pacific Ocean is shrinking due to subduction at the Ring of Fire. 2 24.
Which continents are moving closer to each other? Which are moving farther away? Asia and North America are getting closer because of subduction in the Pacific, while Europe and North America are moving farther away and Africa and South America are also moving farther away. 25. Remember how to identify locations using latitude and longitude. Look this up and practice! 2.2. Earthquakes 26. What are earthquakes? Vibrations in the Earth caused by sudden movement of rock 27. What causes earthquakes? Sudden movement of rock 28. Where are earthquakes most common? Why? At plate boundaries where plates are sliding against each other. 29. What causes the most death and injury in an earthquake? Falling debris from damaged buildings 30. Do earthquake waves carry energy or matter? All waves carry ENERGY, not matter 31. What is the difference between the focus and the epicenter? The focus of the epicenter is the place along the fault where the earthquake begins, while the epicenter is the point on the Earth’s surface directly above the focus. The epicenter is what you would locate on a map. You need to know the depth below the surface to identify the focus. 32. What instrument is used to measure, detect, and record earthquakes? Seismograph 33. Know how to read a seismogram! Look back through your notes at “Can you read a quake?” 34. What are the different types of seismic waves? P waves, S waves, and surface waves. Which type is the fastest? P waves Which type is the slowest? Surface waves Which waves are longitudinal? P waves Which waves are transverse? S waves (surface waves are a combination.) Which layers of Earth do each type travel through? P waves travel through all layers. S waves only travel through crust and mantle. Surface waves only travel through the crust. Which one only travels through solid, not liquid? P waves travel through solids and liquids. S waves only travel through solids and stiff materials. Surface waves only travel through the solid crust. 35. How can you use distance = speed x time (d = vt) to determine lag time? See examples in Plotting the Epicenter Activity (prelab questions) 36. What is lag time? The amount of time between P wave and S wave arrivals at a particular location. The longer the lag time, the farther the location is from the epicenter. How can you use lag time to determine the distance from one city to the epicenter of an earthquake? 37.
where lag time for 100km = 8s Why do you need seismograms from three cities to find the epicenter? This is called triangulation, and when you have data from three cities, you can locate the epicenter because there is only one point given three distances. 3 38.
Know how to use triangulation to determine the epicenter of an earthquake on a map. Know how to use a compass with distances from three cities to locate the epicenter. 39. Do earthquakes only occur at plate boundaries? No, as you saw in Tennessee Shakes, earthquakes can occur in the middle of plates, but it is rare. 2.3. Volcanoes 40. What is the Pacific Ring of Fire? Why is it called that? The Pacific Ring of Fire is an area around the edge of the Pacific Plate where large numbers of earthquakes and volcanic eruptions occur due to the subduction of the Pacific Plate underneath the surrounding plates. It is called that because of the volcanic eruptions. 41. Name the different types of volcanoes. For each type, know: The type of lava The type of eruption (explosive/flowy) How it’s formed An example Volcano Lava Type Eruption Type How it’s formed Example Pari’cutin, Explosive Steep, loosely Cinder Cone “tephra” – Mexico arranged sides ash, cinders, of tephra and bombs Shield Runny lava Flowy Lava hardens Mauna Loa, into flat layers Hawaii Mt. St. Helens, Composite or Combination Both explosive Alternating Stratovolcano tephra and and flowy layers of tephra Washington runny lava and hardened lava Caldera Ash and dust Explosive Top collapses to Crater Lake, Oregon form an enormous caldera Lava bulges up Inside Lava Dome Thick and Lava blocks and blocks vent Mt. St. Helens sticky lava vent, pressure or Novarupta, builds up and Alaska eventually blows its top Iceland Pressure builds Fissure Thin and sticky Explosive up under a crack lava in the Earth’s (sheet lava or surface wall of fire) 42. What is the difference between magma and lava? Magma is molten rock underneath the surface of the Earth, while lava is molten rock once it’s above the surface 43. What is the difference between active, dormant, and extinct volcanoes? An active volcano is one that has erupted in the last 10,000 years. An active volcano can be erupting or dormant. A dormant volcano is an active volcano that is not erupting but is expected to erupt again. An extinct volcano is one that has not erupted in the last 10,000 years and is not expected to erupt again. 4 44.
Identify the parts of a volcano on a diagram. Ash cloud Side vent Crust Vent Lava Conduit Magma Chamber 2.4. Ocean Floor 45. Can you see the ocean floor? What three factors prevent us from going down to see the bottom of the ocean? Other than in the shallowest sections, you cannot usually see the ocean floor. The low temperatures, lack of light, and immense pressure make it difficult to go down and see the bottom of the ocean. 46. What technology have scientists developed in the last 100 years that aid us in “seeing” the seafloor? Sonar is a widely used technique to explore the ocean floor. Sonar uses sound waves – the emitter will send out a sound wave signal and the receiver will detect the sound wave bouncing back. Based on the time, the device will figure out how deep the ocean is at a certain point. When this is done repeatedly, we can “see” what the bottom of the ocean looks like. 47. What features are at the bottom of the ocean floor? Be able to define each and identify each on a diagram. A: Continental Slope – steep incline on the edge of the Continental Shelf B: Seamount – mountains on the seafloor which are completely underwater C: Abyssal Plain – smooth, nearly flat area of the ocean floor D: Mid Ocean Ridge – continuous underwater mountain range at divergent boundaries 5 E: Volcanic Island – Volcanoes on the ocean floor that reach above the ocean surface F: Continental Shelf – gently sloping, shallow area on the edge of continents G: Trench – deep, steep‐sided canyons at subduction boundaries 48. What is the deepest place on Earth? Marianas Trench 49. How have scientists used seafloor features to support the theory of plate tectonics? Mid‐Ocean Ridges are evidence of divergent boundaries and trenches are evidence of subduction boundaries. 3. Chemistry and Water 3.1.
Periodic Table 50. What information can you get from the periodic table? Atomic Number – number of protons or electrons in neutral atom Element Symbol Element Name 51.
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Atomic Mass/Mass Number if rounded – number of protons and neutrons or number of particles in nucleus
What are the three main subatomic particles? protons, neutrons, and electrons Where can you find each of the subatomic particles in the atom? (nucleus/electron cloud) protons and neutrons in nucleus, electrons in electron cloud What electrical charge does each subatomic particle have? Protons are positive, neutrons are neutral, and electrons are negative. What does the atomic number tell you? Tells you the number of protons OR the number of electrons in a neutral atom. The number or protons defines what element an atom is. An atom with 8 protons is an atom of oxygen no matter how many neutrons or electrons it has. What does the mass number tell you? What’s the difference between atomic mass and mass number? The mass number tells you the number of protons plus the number of neutrons, or the number of particles in the nucleus. The atomic mass is the AVERAGE mass of an atom of a particular element. What does it mean to have a neutral atom? The number of protons EQUALS the number of electrons. How do you calculate the number of neutrons in an atom? number of neutrons = atomic number – mass number (SUBTRACT) What is the difference between an atom and a molecule? A molecule is more than one atom bonded together. What is the “glue” that holds atoms together? A chemical bond Properties of Water What types of atoms and how many of each are found in a water molecule? One water molecule is made up of 2 hydrogen atoms and 1 oxygen atom What is a hydrogen bond? Why does it form? A weak bond between water molecules. It forms because the hydrogen atoms in the water molecule are attracted to the oxygen atoms of other molecules. Which state of matter (solid/liquid/gas) has the most hydrogen bonds? 6 63.
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solid In which state of matter do the molecules move the fastest? gas Slowest? solid In which state of matter are the molecules farthest apart? gas Closest together? solid Which state of matter has the lowest temperature? solid Highest temperature? gas Which state of matter has the lowest density? gas Highest density? (You may answer differently for water and for other substances.) liquid for water, solid for most other substances What happens to hydrogen bonds as you heat water? they break Explain at least two reasons why hydrogen bonding makes water special. surface tension, makes ice less dense than water Heat Curve and Density What is the formula for density? Density = mass ÷ volume D = m/V Name two ways that you can change the density of a substance? change the mass, increase the volume What is the density of water (approximately)? 1.0 g/mL At what temperature is water’s density maximum? Why? 4oC because hydrogen bonding moves molecules farther apart at lower temperatures. When will an object float in water? When will an object sink in water? An object will float in water when its density is less than 1.0 g/mL. It will sink when its density is greater than 1.0 g/mL. An object has a density of 0.8 g/cm3. Will it float or sink in water? It will float because its density is less than 1.0 g/mL How does the density of ice compare to the density of liquid water? Ice is less dense than water In general, how does density of cold water compare with the density of warm water? Generally, above 4oC, the density of cold water is greater than the density of warm water In general, how does density compare in solids, liquids, and gases? For most substances, solids have the greatest density, gases have the lowest density, and liquids are in between. Water is an exception because it is most dense as a liquid. Define evaporation, condensation, freezing, and melting in terms of states of matter. Evaporation – turning from a liquid to a gas Condensation – turning from a gas to a liquid Freezing – turning from a liquid to a solid Melting – turning from a solid to a liquid What is the difference between latent heat and sensible heat? Latent heat occurs at phase changes where the temperature is constant. Sensible heat occurs when the temperature is changing in only one state of matter. What changes when adding latent heat? phase Sensible heat? temperature Why does temperature not increase when adding latent heat? The energy goes into breaking bonds between molecules. What is the difference between latent heat of fusion and latent heat of vaporization? 7 83.
Latent heat of fusion is between the states of solid and liquid. Latent heat of vaporization is between the states of liquid and gas. Know how to read a heat curve. Using the phase change graph, be able to identify: The phase(s) of matter present at each segment Location where latent heat of vaporization is being added Location where latent heat of fusion is being added Locations where sensible heat is being added Freezing/melting point and boiling/condensation point Melting Point Latent heat of vaporization
Latent heat of fusion Solid & liquid Liquid & gas Sensible Heat Condensation point Sensible Heat Melting point Freezing point Sensible Heat Identify if the substance is water. You can tell if the substance is water if the melting/ freezing point is at 0oC and the condensation/melting point is at 100oC. The above graph is for water. 84. Which requires more energy – melting ice into water or boiling water into gas? Why? Boiling water into gas takes more energy because ALL of the hydrogen bonds have to be broken to turn from liquid to gas, while melting only requires some bonds to be broken. 85. What is the difference between heat and temperature? Heat is the TOTAL thermal energy in a substance, while temperature is the AVERAGE energy of motion (kinetic energy) of each molecule in the substance. 86. A 50mL cup of 5o water is mixed with a 100mL cup of 80o water. What happens to the temperature? What happens to the heat? Temperature will be a weighted average – around 55OC. The heat of the mixture will be equal to the sum of the two individual heats before the cups were mixed. 87. What happens to the freezing point of water when salt is added? (ice cream) The freezing point of water goes down below 0oC when salt is added. 4. The Ocean 4.1.
Layers of the Ocean 88. As you travel deeper in the ocean, what happens to temperature? Density? Salinity? Temperature decreases, density increases, and salinity increases. 89. Identify the layers of the ocean. What divides the ocean into layers? 8 Surface, thermocline (pycnocline), deep‐sea. Differences in temperature, salinity, and density. 90. Define the thermocline. Middle mixing layer in the ocean where temperature changes rapidly with increasing depth. 4.2.
Chemical Properties of Ocean Water 91. What are the two most abundant elements in the ocean? Hydrogen and oxygen. Together, they make __water__. 92. What are the next two most abundant elements in the ocean? Chlorine and sodium. Together, they make __sodium chloride__, commonly known as __table salt__. 93. Define salinity. The amount of dissolved salt in water. 94. What happens to the density of water as you increase salinity? Density increases as salinity increases. 95. What percentage of the ocean is pure water? 96.5% 96. How are sea surface temperature and sea surface salinity related? In general, areas of higher sea surface temperature have higher salinity due to evaporation. 4.3.
Currents 97. What causes the most surface currents? Wind 98. How can you tell if a current is a warm water current or a cold water current? If it starts in the tropics, it’s a warm water current. If it starts near the poles, it’s a cold water current. 99. Which currents affect the continental US? How do these currents affect the climate of each coast? The Gulf Stream – warm water current that keeps the east coast warmer than it would be without the current. California Current – cold water current that keeps the California climate more temperate. 100. Why do surface currents generally move in a circular pattern? Major surface currents originate because of global wind patterns. Once the currents are formed, they bend because of the Coriolis Effect (to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.) Because of their original direction and then their deflection, they form large circular gyres which move clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. 101. In which direction to surface currents in the northern hemisphere circulate – clockwise or counterclockwise? clockwise 102. What is thermohaline circulation? What drives sinking water? How is it affected by global warming? Large scale ocean circulation including surface and deep waters which are driven by differences in density. As surface currents in the Atlantic move northward, the water evaporates, cools, and freezes. All three of these processes lead to increased density which results in sinking in the Northern Atlantic. Global warming may not only raise sea levels, but slow the thermohaline circulation, because density would not increase as much due to melting in the Northern Atlantic and the water would then not sink as fast. 9 This could affect climate all over the globe by slowing the movement of heat away from the tropics and could result in another ice age. 4.4.
Waves 103. Do waves carry matter or energy? energy 104. Identify the parts of a wave on the diagram: 1 2 4 5 6 3
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1: Amplitude 2: Wavelength 3: Wavelength 4: Wave height 5: Crest 6: Trough When do ocean waves start to “break”? In shallow water, friction causes the bottom of the wave to move slower, while the top continues to move at the original speed. A breaker is formed when the top of the wave falls over. How do orbital waves differ in deep and shallow water? Orbital waves are circular waves. Deep water orbitals become increasingly smaller but never touch the ocean floor. Shallow water orbitals flatten out as they reach the ocean floor. What causes longshore current? In what direction does it travel? Longshore current is caused by waves approaching the shore at an angle. The longshore current travels parallel to the shore and carries sand and sediment. Tides 108. What are tides? The periodic variations in the surface water levels of oceans, bays, gulfs, and inlets. 109. What causes tides? The gravitational attraction of the moon and the sun on the earth. 110. If the mass of an object is greater, will the pull on that object by gravity be stronger? yes, gravitational attraction will be stronger if the mass is greater or the distance between objects is smaller. 111. How many high tides in a day usually? 2 How many low tides? 2 So a high tide and a low tide are separated by about _6_ hours. 112. What is the difference between a spring tide and a neap tide? 10 Spring tides bring extreme high tides and extreme low tides and occur when the sun, earth, and moon are in line with one another. Neap tides bring high and low tides which are not as extreme and occur when the sun, earth, and moon form a 90o angle with one another. 5. The Beach 5.1.
Beach Features 113. Define erosion and deposition. erosion – process by which the products of weathering are transported deposition – process by which products of weathering are deposited in a new location 114. Give examples of geological features constructed by the process of longshore current. barrier islands, spits, tombolos 115. Draw a diagram and label the parts of a typical beach. dune
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scarp sandbar 116. Which beach feature(s) are ALWAYS underwater? trough and sandbar 117. If the ridge is covered, does this mean high tide or low tide? high tide 118. What manmade features help prevent beach erosion? groin, jetty, seawall, and breakwater 6. Bringing it all together… 119. How are convection and density related? Differences in density drive convection currents in a material which is unevenly heated. 120. What is convection? How does convection happen in oceanography and meteorology? Convection is the transfer of heat through the movement of heated material. In both oceanography and meteorology, convection is driven by uneven heating of materials. 121. Give examples of convection from both oceanography and meteorology? Oceanography examples: ‐ convection currents in the mantle which aids the movement of tectonic plates. ‐ convection currents in the ocean Meteorology examples: ‐ convection currents in the atmosphere lead to global wind patterns ‐ convection currents in the atmosphere are responsible for local wind patterns 11 including land and sea breezes ‐ convection currents in a cumulonimbus cloud result in the formation of hail There are many more examples. Come up with some on your own. 122. Give as many examples as you can of how oceanography and meteorology are related. In other words, how does the ocean affect weather/climate or how does weather/climate affect the ocean? ‐ Winds cause the formation of surface currents and ocean waves. ‐ Cold and warm water currents affect the climate of coastal areas. ‐ Precipitation affects salinity and therefore density of the oceans. ‐ Climate differences around the globe affect thermohaline circulation. ‐ Evaporation from oceans and other bodies of water provide the atmospheric moisture which enables the formation of clouds and precipitation. ‐ Events like El Niño and La Niña link winds and weather to ocean currents and upwelling. There are many more examples. Come up with some on your own. 12