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Final Study Guide I
Name __________________________________
Date____________
Period __________
1. What is the circumference of the Earth at the equator? 25,000 mi
2. About how long would it take to drive around Earth’s equator at 60 mph? 17 days (1 month)
3. About how long would it take to fly around Earth’s equator? 45 hours
4. What percent of Earth’s surface is covered in water? 71%
General Ocean
5. The global ocean contains ___60__% of Earth’s water and has an average depth of about 2.5 mi.
6. Earth’s largest ocean is the PACIFIC Ocean and Earth’s smallest ocean is the ARCTIC Ocean.
7. The Pacific Ocean was named by FERDINAND MAGELLAN “Pacific” means PEACEFUL.
8. MAGELLAN tried to sail around the world but was killed by Philippine natives with spears & rocks even
though he & his men had guns & cannons.
9. Modern oceanography began in the decade of the 1850’S when American Naval officer MATTHEW F.
MAURY wrote the first book on oceanography. Between 1872 and 1876, the H.M.S. CHALLENGER
gathered extensive oceanography data.
10. In the 1940’s, JACQUES COUSTEAU invented the first fully functional aqua-lung. He also made an
awesome tv show that brought the underwater world to land lubbers everywhere.
11. What is sonar used for? LOCATING OBJECTS, COMMUNICATION, MAPPING SEAFLOOR
12. Sonar involves bouncing SOUND waves off of the ocean floor.
13. 50 m = 164 ft
1 m = ________ ft
3,000 km = 1860 mi
d = st
D = st/2
14. How many meters deep is the water if the sonar time is 0.350 s?
15. How many meters deep is the water if the sonar time is 6.70 s?
Plate Tectonics & Features of the Ocean Floor
16. The Theory of PLATE Tectonics states that Earth’s crust is broken into huge pieces that slowly move around. It
explains how mountains are formed and how EARTHQUAKES and VOLCANOES occur.
17. At CONVERGENT boundaries, Earth’s tectonic plates move towards each other. When one of the plates is denser,
it sinks under the other. This is called SUBDUCTION. At areas of subduction you can find deep OCEAN
TRENCHES on the ocean floor and active VOLCANOES on the top plate.
18. An underwater mountain range called the mid ocean ridge is found at a DIVERGENT boundary where plates move
apart. Rocks are near the mid ocean ridge are (younger/older) than rocks further away.
19. The ABYSSAL PLAINS are the flattest places on Earth because they are COVERED IN FINE SEDIMENT.
20. TRENCHES are the deepest features in the ocean floor, and they exist at SUBDUCTION zones (CONVERGENT
boundaries). The deepest spot in the ocean, called the CHALLENGER Deep, is in the MARIANAS Trench south of
JAPAN. It is about 37,000 ft deep...almost 7 miles!
21. Underwater volcanic mountains are called SEAMOUNTS
22. A flat-topped submerged seamount is called a GUYOT.
23. Underwater mountain ranges called MID OCEAN ridges are found along DIVERGENT boundaries. ICELAND
and the AZORES islands are two of the few places where a mid-ocean ridge rises about sea level.
24. In the SUNLIT zone, (0-600 ft) photosynthesis can occur. 90% of ocean life lives here. PHYTOPLANKTON form
the base of the food chain.
25. In the TWILIGHT zone, 600 ft to 3000 ft), there is very little sunlight…not enough for photosynthesis to occur. At
this depth, the human eye could not see any color.
26. In the MIDNIGHT zone, there is no sunlight. Most life in this zone lives in HYDROTHERMAL vent communities.
Bacteria use methane and hydrogen sulfide to create food via CHEMOSYNTHESIS, forming the base of the food
chain. Unlike almost all other animals on Earth, these creatures live off geothermal energy (heat energy inside Earth).
They don’t need sunlight! BACTERIA form the base of the food chain near hydrothermal vents and cold seeps.
27. Cold seeps are underwater lakes at the bottom of the ocean. The water in the lake is BRINE.
28. Hydrothermal vents were discovered in 1977 near the GALAPAGOS Islands. Here water seeps into cracks in the
ocean floor, becomes superheated (662oF) and dissolves minerals, then shoots out of the ocean floor. Towers of
minerals called CHIMNEYS form. This is probably how many of Earth’s mineral deposits formed.
29. Ring shaped coral islands are called CORAL ATOLLS.
30. The ALGAE living inside coral provide the coral with food and give them their awesome colors. The GREAT Barrier Reef,
the largest coral reef on Earth, is off the NORTHEAST coast of Australia.
31. Blue holes were created WHEN SINKHOLES filled up with water when ice melted at the end of the last ice age.
32. 1 nautical mile = 1.15 mi
1 knot = 1.15 mi/hr
1 fathom = 6 ft
33. Which rock on the ocean diagram is oldest? THE ONE FURTHEST FROM THE MID OCEAN RIDGE
34. Which margin is active, the one on the left or the one on the right? How do you know? RIGHT, TRENCH THERE
Name __________________________________
Final Study Guide II Period __________
Ocean Sediments
35. Most sand on beaches is made of tiny pieces of ROCK from land. It is carried into the ocean by
RIVERS__.
36. Most beaches are sandy instead of muddy because the COARSER particles settle out near shore, but the
finer MUD particles don’t settle out until they reach the slow moving waters of the open ocean.
37. The average depth of sediments on the ocean floor is 1300 feet.
Properties of Ocean Water
38. In 221 pounds of water from the Dead Sea, there would be 65.04 pounds of salt. What is the salinity of the
Dead Sea? (Give answer in % and o/oo.)
39. Ocean water has a salinity of 3.51 %. How many pounds of salt are in one gallon of ocean water (8.35 lbs)?
40.
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44.
Where did the oceans come from? VOLCANOES & COMETS
Water molecules “stick together”, which is called COHESION
SURFACE TENSION is the tendency of surface of a liquid to resist an outside force.
Why can water bugs sit on water? IT HAS A HIGH SURFACE TENSION
How does the high heat capacity of water help Earth? KEEPS EARTH FROM GETTING TOO COLD
OR HOT
45. List the 3 main gases found in ocean water. NITROGEN OXYGEN CARBON DIOXIDE
46. A carbon SOURCE releases more carbon than it absorbs and a carbon SINK absorbs more carbon than it
releases. The ocean is a carbon SINK because it removes carbon dioxide from the atmosphere.
47. The ocean is absorbing (more or less) carbon than it used to because Earth is getting (warmer/colder).
48. How many gallons of water are in the ocean? 36 QUINTILLION Humans use 1 QUINTILLION gallons
of fresh water per year.
49. Which is denser, warm water or cold water? COLD Fresh water or salt water? SALT
50. What are 2 processes that increase the salinity of ocean water? EVAPORATION FREEZING
51. What are 3 processes that decrease the salinity of ocean water? ICE MELTING, RIVERS ENTERING
OCEAN, PRECIPITATION
52. The top 100 – 300 meters (328 - 1000 ft) of ocean water that is warmed by the sun is called the MIXED
layer. Its temperature is affected by AMOUNT OF SUNLIGHT and SURFACE CURRENTS.
53. In cold regions of the ocean, PACK ICE insulates the ocean water. It prevents the water from cooling
through EVAPORATION. This is why pack ice only gets 5 m (16 ft) thick. Ice is LESS dense than water,
so it floats. If it didn’t float, the ocean would FREEZE.
54. Layer of ocean water in which the temperature drops with increased depth - THERMOCLINE
55. Salt is washed into the oceans by RIVERS, falls into the water when VOLCANOS erupt,
HYDROTHERMAL VENTS, CHEM. WEATHERING OF NEW SEA FLOOR.
56. Pure water is blue because it ABSORBS red, orange, and yellow light more than blue, which it REFLECTS. A glass of water
appears clear because there’s not much water there, so almost none of the light is absorbed. The thicker the layer of water is, the
bluer it will appear.
57. One gallon of water weighs about 8 pounds.
Life in Oceans
58. In general, where does upwelling occur? ALONG COASTS
59. Because the Earth is ROTATING, the water doesn’t move in the exact direction of the wind.
60. Explain how upwelling occurs. (3 steps) 1. Wind blows PARALLEL to shore. 2. Surface water moves AWAY FROM SHORE.
3. COLD, NUTRIENT RICH WATER RISES.
61. Upwelling is important because it brings NUTRIENTS to the surface.
62. What are 5 things found in areas of upwelling? NUTRIENTS, PHYTOPLANKTON, ZOOPLANKTON, SMALL FISH, BIG
FISH, MAMMALS, BIRDS, FISHERMEN
63. What is el Nino? AN ABNORMAL WARMING OF THE SURFACE WATER OFF THE COAST OF PERU
64. Organisms that float or drift freely in aquatic environments are called PLANKTON.
65. Organisms that swim actively in water are called NEKTON.
66. Organisms that live on the ocean floor are called BENTHOS.
67. PHYTOPLANKTON form the base of most marine food webs.
68. Jellyfish have no BRAINS, HEART, OR BONES. They’re basically a floating STOMACH.
69. What are the cells that sting you called? NEMATOCYSTS Should you pee on a jellyfish sting? ONLY AS LAST RESORT
70. What are the 3 steps you should follow if stung by a jellyfish?
a.
RINSE WITH SALTWATER
b.
APPLY VINEGAR OR MEAT TENDERIZER
c.
RUB WITH SAND, SCRAPE WITH CREDIT CARD, OR SHAVE
71. HAB stands for HARMFUL ALGAE BLOOMS Sometimes referred to as RED tides, they can be harmful by creating TOXINS
or causing all of the oxygen in the water to be used up. An area in the ocean without oxygen is called a “dead zone”.
72. Do fish sleep? NO, THEY REST
73. people are killed annually by sharks = 10 Sharks killed annually by people = 100 MILLION
74. What should you while being attacked by a shark? ATTACK THE EYES, GILLS, & NOSE
75. What is the largest FISH in the ocean? What does it eat? WHALE SHARK, PLANKTON
76. The biggest animal ever is the BLUE WHALE. It can reach a length of 120 feet. It is almost extinct due to OVERHUNTING.
It has a life span of about 90 years.