Sediment Types
Sediments made from rocks on the continents
What is terrigenous?
Which sediment type is derived directly from the physical and chemical weathering of continental rocks?
Lithogenous
Calcareous oozes are primarily composed of which chemical compound?
Calcium Carbonate
Underwater landslides along continental slopes create layered sediment deposits known as:
Turbidites
At what general ocean depth threshold does the Calcium Carbonate Compensation Depth (CCD) typically occur?
4,000--5,000 meters
At what general ocean depth threshold does the Calcium Carbonate Compensation Depth (CCD) typically occur?
4,000--5,000 meters
Which single-celled protozoans produce hard tests made of silica (SiO2)?
Radiolarians
These sediments are also called oozes
What is biogenous?
A deep-sea sediment deposit is classified as an ooze if it contains at least what percentage of microscopic biogenous remains by weight?
30%
Why do cosmogenous sediments make up less than 1% of all sea floor sediment deposits?
The influx rate from space is extremely small and heavily diluted by terrestrial and biological inputs.
Where on the ocean floor would you expect lithogenous sediment thickness to be the greatest?
Along continental margins and near major river mouths
Neritic sediments are found
What is on the continental shelf
Which grain size would you expect to find closest to shore in high-energy coastal environments?
Coarse sand and gravel
Explain the chemical and biological differences between calcareous ooze and siliceous ooze.
Calcareous ooze is composed of calcium carbonate (CaCO3) produced by organisms like foraminifera or coccolithophores.
Siliceous ooze is composed of silica (SiO2) produced by organisms like diatoms or radiolarians.
Calcium carbonate sediments form by
What is precipitation
Which microscopic photosynthetic algae are responsible for forming siliceous ooze?
Diatoms
Extremely fine lithogenous particles that drift into the deep ocean and settle very slowly over millions of years form
Abyssal Red Clay
Why do calcareous oozes rarely accumulate on the sea floor below the CCD?
High water pressure, low temperature, and acidity cause calcium carbonate to dissolve.