Homework 4

On average, at what ocean depth does calcite readily dissolve into seawater?

4500 meters (14,764 feet)

Which of the following statements about the calcite compensation depth (CCD) is correct?

Below the calcite compensation depth (CCD), physical conditions cause calcium carbonate to dissolve.

Which of the following explains why calcareous ooze is sometimes found below the calcite compensation depth (CCD)?

Calcareous ooze can be deposited above the CCD and covered with other sediment, which protects it as the tectonic plate, and the ooze moves into deeper water.

Of the following sediments, which one(s) is/are considered hydrogenous?

Manganese nodules Coatings of metal sulfides near black smokers

Of the following, which energy resource(s) can be extracted from marine sediments?

Petroleum Gas hydrates

Of the following sediments, which one(s) is/are considered biogenous?

Tests of foraminifera Radiolarian ooze

Why do some organisms thrive in warm surface waters?

Warm water is generally saturated in carbonate.

Which of the following are examples of neritic sediments?

beach sand evaporite deposits

Which of the following sediments would you expect to find in a lagoon?

broken bits of coral salt

Where might one find calcareous oozes on the seafloor?

buried beneath abyssal clay buried beneath siliceous oozes along the crests of mid-ocean ridges, above the CCD

Which sediment below cannot accumulate below the CCD?

calcareous tests

Where on the ocean floor do abyssal clays develop?

on the deep-ocean floor, far from land

Which of the following organisms thrive in cold surface waters?

radiolarians siliceous organisms

In which of the following environments would you expect lithogenous sediment to be the dominant sediment type?

the abyssal plains at the base of the continental slope a sandy beach

Which of the following are examples of pelagic sediments?

volcanic dust biogenic ooze abyssal clay

Which of the following factors affect the distribution of biogenic oozes on the seafloor?

water depth dissolution biological productivity seafloor spreading

Where is calcareous ooze most likely to be found in surface sediments in the ocean?

Calcareous ooze is most likely to be found in relatively shallow areas with warm surface water.

Tektites and chondrites fall under which sediment classification?

Cosmogenous