Geology Cafe

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) 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 beach sand

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

5. Salt in seawater comes from:
a) the mechanical and chemical breakdown of rocks on land.
b) comes from salts dissolved in water running off of the continents.
c) the concentration of water through evaporation of ocean water.
d) all of the above.

6. 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

7. 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.

8. 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.

9. A “turbidite” is a kind of rock formed from:
a. sediments deposited by an underwater landslide on a deep-sea fan.
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.

10. Which deposits are not likely found on a continental shelf?
a) deltas.
b) oozes.
c) carbonates.
d) beaches.

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

12. 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.

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

14. 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.