Oceanography 101

Quiz Questions - Chapter 6 - Marine Sediments

1. Manganese nodules are considered to be:
a. hydrogenous sediments.
b. terrigenous sediments.
c. biogenous sediments.
d. cosmogenous sediment.

2. Which is NOT a lithogenous sediment?
a. river sand
b. quartz-rich beach sand
c. lime mud
d. wind-blown dust

3. Which is NOT a biogenous sediment?
a. calcareous oozes
b. siliceous oozes
c. coral reef deposits
d. quartz-rich beach sand

4. Anhydrite is a “dry” (water free) variety of:
a. gypsum.
b. rock salt.
c. limestone.
d. quartz sand.

5. Where are the thickest accumulations of sediments mostly found around the world?
a. the outer margins of continental shelves
b. on continents
c. on ocean ridges
d. on abyssal plains

6. Which of these best describe weathering?
a. the transfer of rock material downslope by gravity
b. the mechanical and chemical disintegration of rock on or near the surface
c. the alteration of igneous rocks into sand and clay minerals
d. the removal of material by flowing water, air, or ice

7. The high level of salt in seawater comes from:
a. the weathering and erosion of rocks on the surface or the seafloor.
b. salts dissolved in water flowing off of the continents or water flowing through sediments or rocks underground.
c. the concentration of water through evaporation of ocean water.
d. all of the above.

8. Regarding the size of clastic sediment particles, which selection below arranges particles from LARGEST to SMALLEST?
a. cobbles - boulders - gravel - sand - silt - clays
b. cobbles - boulders - gravel - silt - sand - clays
c. boulders - cobbles - gravel - silt - sand - clays
d. boulders - cobbles - gravel - sand - silt - clays

9. Which of the following would be considered a clastic sedimentary rock?
a. shale
b. conglomerate
c. sandstone
d. mudstone
e. all of the above

10. A sedimentary rock formed from the consolidation of gravel with a matrix of some sand and silt is called:
a. sandstone.
b. limestone.
c. conglomerate.
d. graywacke.

11. As sediments are transported by flowing water, over time, they tend to become:
a. more angular and poorly sorted.
b. more rounded and poorly sorted.
c. more angular and well sorted.
d. more rounded and well sorted.

12. A layer of sediment or sedimentary rock layer only a small fraction of an inch (less than a centimeter) in thickness, and is typically associated with fine-grained sediments is called:
a. a rock formation.
b. bedding.
c. lamination.
d. strata.

13. If you find a rock that was part of an ancient coral reef, you know that the rock must have formed in:
a. cold, deep water.
b. turbid waters, such as near a river delta.
c. cool, clear, shallow, polar water.
d. warm, clear, shallow, tropical water.

14. A turbidite is a kind of rock formed from:
a. sediments deposited by an underwater landslide on a deep-sea fan on a continental rise.
b. sediment deposited around a shallow water coral reef.
c. sediment deposited along a beach near a river delta.
d. sediment that accumulates from the underwater rain of pelagic biogenous sediments.

15. Which deposits are not likely found on a continental shelf?
a. delta sand and mud deposits.
b. siliceous oozes.
c. carbonate mud and reef deposits.
d. offshore bars and beach sand deposits.

16. Where are the thinnest sediments generally found in deep ocean basins?
a. the mid-oceanic ridges.
b. trenches.
c. abyssal plains.
d. along a continental rise.

17. Coccolithopores are single-cell plants that grow in the warmer upper layers of the ocean. Their remain accumulate on the seabed forming:
a. siliceous ooze.
b. calcareous ooze.
c. turbidites.
d. mudstone.

18. What kind of sediment or rock are you likely NOT to find below the Carbonate Compensation Depth (CCD)?
a. lime mud
b. siliceous ooze
c. basalt
d. all of the above

18. Diatoms are the most abundant form of microplankton in the world oceans. Their remains accumulate on the seabed forming:
a. siliceous ooze.
b. calcareous ooze.
c. turbidites.
d. limestone.

20. A siliceous rock that forms from the accumulation of the remains diatoms and radiolarian on the seafloor is called:
a. chalk.
b. chert.
c. graywacke.
d. quartz sandstone.