Practice Questions for Chapter 17
Geology 1200
Use these questions to test your knowledge of Chapter 17.
A. Short answer:
1. A beach is a narrow strip of land, washed by ______or tides.
2. Waves are produced by the action of ______.
3. ______is defined as the distance a wave-producing wind travels before hitting land.
4. The water within a mid-ocean wave has an ______motion.
5. Waves erode coastal rocks by forcing water and ____ under high pressure into rock crevices.
6. A ______is a pile of sand on the backshore deposited by a storm.
7. The movement of sand along a beach face is called beach ______.
8. Rock walls intended to protect boats at anchor from waves are called ______.
9. Roots of ______trees dissipate wave energy, creating quiet waters where coastal deposition can occur.
10. Coral Reefs around eroding volcanoes eventually form an ______.
B. Match the Terms.
1. Hook_____ a. cliff that juts seaward
2. Tombolo____ b. curved spit
3. Primary coast____ c. products of marine erosion and deposition
4. Jetty ____ d. deposition behind sea stack
5. Wave refraction____ e. generated by nonmarine processes
6. Headland_____ f. circular coral reef
7. Atoll_____ g. parallel to main coast
8. Secondary coast______h. keeps the inlet clear of sediment
9. Barrier Island______i. mostly due to the moon
10. Tides ____ j. lower speed in shallow water
C. True or False? Circle the correct answer.
1. Waves are produced by the gravitational pull of the Moon. True or False?
2. The water within a surf zone travels with translatory motion. True or False?
3. Wave refraction refers to the bending of the direction of travel of waves as part of the wave front drags bottom. True or False?
4. Our small moon has much more tidal influence than the Sun because the Moon is closer. True or False?
5. Tidal bores can move water upstream, against the normal flow. True or False?
6. Coastlines that are gently sloping are easier to erode than coastlines with steep cliff faces. True or False?
7. Barrier Islands line the East Coast for 850 miles and the Gulf Coast for an additional 850 miles. True or False?
8. Mangrove swamps help to extend the coastline seaward. True or False?
9. Long Island and Cape Code began as Terminal Moraines when sea-level was lowered by glaciation. True or False?
10. Erosional features such as sea stacks and wave-cut benches may be found along recently rifted divergent plate boundaries. True or False?
D. Multiple choice:
- A beach is defined as:
(a) the entire region bordering a body of water.
(b) the precise boundary where a body of water meets dry land.
(c) a sandy strip of land.
(d) a narrow strip of land, washed by waves or tides.
- Waves are produced by:
(a) the gravitational pull of the Moon.
(b) the gravitational pull of the Sun.
(c) the rotation of the Earth.
(d) the action of wind.
- Due to the influence of fetch on the production of ocean waves, the largest wave would be expected to occur:
(a) in the Pacific Ocean at the equator.
(b) in the Atlantic Ocean between Africa and northern South America.
(c) in the northern parts of any ocean.
(d) in the ocean south of the southern tip of South America.
- Which of the following statements about the motion of water within a wave is NOT true?
(a) The water within a mid-ocean wave has an oscillatory motion.
(b) The water within a mid-ocean wave travels toward a shoreline with a translatory motion.
(c) The water within a surf zone travels with translatory motion.
(d) The water within a surf zone moves toward the beach.
- Wave refraction refers to:
(a) the change within an ocean wave from oscillatory motion to translatory motion.
(b) the bending of waves until they break, or fracture, to become breakers within the surf zone.
(c) the bending of waves by constructive or destructive interference, as the waves encounter other waves.
(d) the bending of the direction of travel of waves as part of the wave front drags bottom.
- Longshore currents are propelled by:
(a) tidal fluctuations.
(b) the zigzag motion of swash and backwash, i.e. wave reflection
(c) wave refraction.
(d) destructive interference between currents.
- The Sun’s proportional influence over tides is best explained by the fact that:
(a) the Sun is larger than the Moon.
(b) only one side of the Earth is facing the Sun at any given time.
(c) solar warming initiates movement of water molecules.
(d) gravitational influence decreases as distance increases.
- Two high tides occur on opposite sides of the Earth because:
(a) one is caused by the Moon and one by the Sun.
(b) one is in the Southern Hemisphere and one is in the Northern Hemisphere.
(c) the gravitational pull of the Moon and the lack of pull on the opposite side.
- A turbulent tide that moves up a stream and can reverse the direction of stream flow is called:
(a) a reverse flood tide.
(b) a reverse current.
(c) a tidal bore.
(d) a tidal flood.
- The principal mechanism by which waves erode coastlines is:
(a) abrasion by the sediment load.
(b) by forcing water and air under high pressure into rock crevices.
(c) dissolution.
- All of the following conditions increase the erosion of coastlines EXCEPT:
(a) soft or fractured bedrock.
(b) coastlines with prominent headlands.
(c) coastlines that are gently sloping.
(d) coastlines oriented perpendicular to the dominant wind direction.
- Erosion of an irregular coastline begins with:
(a) headlands.
(b) sea stacks.
(c) sea caves.
(d) wave-cut benches.
13. Which of the following statements about beaches is NOT true?
(a) The beach face is the portion of the beach visible at high tide..
(b) The foreshore extends from the low- to the high-tide line.
(c) The backshore extends from the high-tide line to the sea cliff or vegetation line.
(d) A berm is a horizontal bench or mound deposited by storm waves.
14. The most likely location for the formation of a spit is:
(a) landward from a sea stack.
(b) seaward from a barrier island.
(c) at the base of a cliff.
(d) at the entrance to a bay.
15. Which man-made structure is designed specifically to interrupt the longshore current and trap sand?
(a) Spit.
(b) Breakwater.
(c) Groin.
(d) Jetty.
16. Which man-made structure is built in pairs to extend the banks of a stream beyond the coastline?
(a) Spit.
(b) Breakwater.
(c) Groin.
(d) Jetty.
17. The main difference between a primary coast and a secondary coast is:
(a) primary coasts are much longer than secondary coasts.
(b) primary coasts represent the main coastline, while secondary coasts are the shoreline within coastal inlets.
(c) primary coasts are shaped principally by nonmarine processes, while secondary coasts are shaped primarily by marine processes.
(d) primary coasts are relatively even, smooth coastlines, while secondary coasts are characterized by numerous headlands and inlets.
18. Which of the following statements about mangrove swamps is NOT true?
(a) Mangroves live in standing tidal water in tropical climates.
(b) Mangrove swamps help to extend the coastline seaward.
(c) Mangroves grow an extensive root system that dissipates much of the energy of waves.
(d) Many mangrove swamps are endangered by coastal erosion.
19. Variations in the northeastern United States coastal topography are primarily due to:
(a) inundation of stream valleys as sea level rises.
(b) submergence due to the weight of continentally derived sediments.
(c) the redistribution of wave action by barrier islands.
(d) past glacial activity and diverse bedrock composition..
E. Short Answer
1. Describe the methods used to protect coasts from wave erosion and keep shipping inlets clear.
2. Discuss both local and global factors that influence change in sea level.