Marine sediment SG

what is the Pelagic zone?

It is the abyssal plane, where there is deeper water deposits, FINER-grained sediments that have deposited slowly.

What is sediment texture?

The size and shape of particles. It can be

\-work pieces of rocks

\-remains of living organisms

\-minerals dissolved in seawater

\-from outer space

Where do marine sediments come from?

From suspension settling, sediments settle out of water and accumulate on the ocean floor

Will you find well-sorted sediments closer to the coast or closer to the mountains?

Closer to the coast

What are lithogenous sediments?

They came from erosion of rocks from continents

What is the Neritic zone?

It is in the continental shelf (closer to land), and is of shallow-water deposits. Mostly lithogenous sediments settle here as they are settled quickly.

What is biogenous sediment

Skeletal remains of once-living organisms.

what are the two most common chemical compounds found in biogenous sediments

Macroscopic (shells, bones, teeth) remains and microscopic (tiny shells and tests)

What are tests?

Shells of microscopic organism

T

What are siliceous ooze composed of?

Tests from diatoms and radiolarians generate siliceous ooze

What are diatoms

Microscopic algae, They photosynthesize so they need strong sunlight and are found in the upper sunlit surface waters

what are radiolarians?

microscopic single celled protozoans. They do not photosynthesize but rely on external food sources such as bacteria and plankton.

What are foraminifera

The produce a hard calcium carbonate test in which the organism lives. They resemble shells on the beach.

what are cocolithophores?

Photosynthetic algae, When organisms dies, the individual plates coccoliths disaggregate and can accumulate on the ocean floor as coccolith ooze. When this ooze lithifies over time, it forms a white deposit called chalk (CALCIUM BASED)

What is calcareous ooze?

Deposits of tests from foraminifers, coccoliths

What controls the distribution of biogenous sediments?

organisms like plankton when Turbitheir exoskeletons break down.

What kind of sediment dominates the neritic zone?

lithogenous sediment, may contain biogenous sediment

What kind of sediment dominates the pelagic zone?

Volcanic ash (volcanic eruptions) Wind-blown dust Fine-grained material transported by deep ocean currents

Understand how siliceous ooze accumulates in areas of high productivity.

The accumulation of siliceous ooze begins with the growth and reproduction of siliceous microorganisms in surface waters. As these organisms die, their silica-based skeletons sink to the seafloor and accumulate over time. In areas of high productivity, this process can lead to the formation of thick deposits of siliceous ooze.

Understand how calcium carbonate is sensitive to depth and water temperature.

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pressure is greater, the water is colder, and it contains greater amounts of carbon dioxide, which forms carbonic acid which dissolves them

What is the lysocline

The depth of the ocean in which pressure is high enough and the temperature is low enough

what is CCD?

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Depth where CaCO3 readily dissolves. No calcite deposition occurs below this depth.

Understand how sea floor spreading at mid ocean ridges plays a role in calcareous ooze present below the CCD line.

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The calcareous ooze accumulates in the ridge axis area and can eventually be buried beneath younger sediments transported away from the ridge axis.

hydrogenous marine sediments.

Came from chemical reactions in the water

The environment in which the sediment is deposited

Mountains to ocean floor

Sediments can be transported by

Water, ice (glacier) and wind.

What does quartz contain

Sio2 (silicon and oxygen)