geography homework

15. Engineers often build ______________ perpendicular to a beach in an effort to trap sand and prevent beach erosion.

Select one:

a. groins

b. levees

c. berms

d. spits

16. In the winter, a beach is typically:

Select one:

a. narrow with sand mostly in offshore bars

b. narrow and covered with sand

c. broad and covered with sand

d. broad with sand mostly in offshore bars

17. A smooth, gently sloping surface on the California coast positioned high above the beach but still covered with seashells and beach sand is called:

This feature is pictured below. (The golf courses were built thousands of years after it formed.)

Select one:

a. beach face

b. flood plain

c. wave-cut platform

d. marine terrace

e. landslide toe

18. Which statement best describes what happens to waves as they move closer to the coast?

Select one:

a. They become taller and steeper.

b. Their motion becomes more circular.

c. Their motion does not reach the seafloor.

d. They become more widely spaced.

19. Sea-cliff erosion is a major issue along the coast of Pacifica, located south of San Francisco. Go to the following USGS web site, which describes coastal erosion along the U.S. West Coast during the 1997-98 El Nino: http://coastal.er.usgs.gov/lidar/AGU_fall98/. 

Figures 3 and 4 show the amount of cliff erosion at Pacifica during that one winter... The data on Figure 4A show the sea cliff at this part of Pacific retreated by how much?

Select one:

a. 4-6 meters.

b. 10-13 meters.

c. 2-3 meters.

d. 7-9 meters.

20. Cave formation is mostly favored by:

Select one:

a. the solubility of the bedrock

b. the geothermal gradient

c. unusually high precipitation

d. the relative height of the water table

21. Which condition is not necessary for sinkholes to form

Select one:

a. lowering of the groundwater table

b. dissolution of bedrock

c. subsidence

d. groundwater flow

22. Which geologic feature is not related to sinkholes (i.e., can for due to similar processes)?

Select one:

a. karst

b. cave

c. lake

d. geyser

23. Why does the state of Florida have limestone as bedrock (a rock easily dissolved by water!)

Select one:

a. sea level was higher during the last glacial minimum

b. sea level was higher during the last glacial maxima

c. sea level was lower during the last glacial minimum

d. sea level was lower during the last glacial maxima

24. Which of the following is not a sign of a sinkhole?

Select one:

a. cracking pavement and walls

b. surface water flow that vanishes into the ground

c. doors that shut tightly

d. damage to home foundations

25. Geyser formation is mostly favored by:

https://www.youtube.com/watch?v=X4zA_YPCyHs

https://www.youtube.com/watch?v=x9UEKCYlM-I

Select one:

a. high solubility of the bedrock

b. unusually high precipitation

c. a high geothermal gradient

d. the height of the water table

26. Arrange the following 6 steps necessary for a geyser eruption in correct order, from beginning to end:

https://www.youtube.com/watch?v=X4zA_YPCyHs

And, yikes! Beware...

https://www.youtube.com/watch?v=AygmNZ_FVtU

1.Continued heating from below warms the entire fluid until if finally boils

Answer 1

Choose...123456

2.Cooler shallow groundwater helps raise the water level in the conduit over time

Answer 2

Choose...123456

3.A subsurface conduit fills with superheated water that rises from passageways in the rock (fractures) below the conduit

Answer 3

Choose...123456

4.Siliceous sinter (a hydrothermal mineral) is deposited where the geyser reaches the ground surface and constricts the opening

Answer 4

Choose...123456

5.The cooler water and overall weight of the fluid inhibits boiling, thus pressure builds in the system

Answer 5

Choose...123456

6.Boiling reduces pressure for the system, and a phase change turns much of the water into a violent eruption of steam

Choose….123456

27. As you now know, the east coast of North America is a passive tectonic margin. Choose the best explanation for why a wave-cut terrace could feasibly be found along this coastline:

Select one:

a. The east coast is submerging due to repeated earthquakes

b. The east coast is emerging due to repeated earthquakes

c. waves are actively eroding the edge of the continent

d. A long time ago, sea level must have been lower than it is today

e. A long time ago, sea level must have been higher than it is today