Distribution of Clays Types of Ooze Calcareous Ooze

Distribution of Clays

Types of Ooze �Calcareous Ooze: Forms mainly from shells of Foraminifera-Planktonic, amoeba-like animals Pteropods- small plaktonic mollusk (snail) Coccolithophores- Planktonic algae �Calcareous ooze accumulation dependent upon the carbonate compensation depth, which is about 4, 500 meters deep on average. Below this depth, no calcareous ooze accumulates and animals cannot make shells out of calcium carbonate (calcite).

Carbonate Compensation Depth (CCD) �Depth is deeper in warm waters and shallower in cold waters �About 48% of all deep-ocean sediments are calcareous oozes.

Siliceous Ooze �Forms mainly from shells of: Radiolarian-planktonic amoeba-like animals. Occur in equatorial regions, particularly in the zone of equatorial upwelling west of South America. Diatoms-Efficient phytoplanktonic single-celled algae. Occur mostly in the Antarctic where strong ocean currents and seasonal upwelling support them. Siliceous ooze can dissolve in deep water but occurs much more slowly than calcareous ooze. This means it can accumulate more quickly.

Distribution of Diatoms

Distribution of Pelagic Sediments

Hydrogenous Sediment �Often use biogenous and terrigenous sediments as a nucleus to form a larger, chemically altered precipitate. �Manganese Nodules: Composed of iron oxides and magnesium. Grow at 1 -10 mm per million years Size of a potato but can be larger Located mostly in Pacific where 20 -30% of the ocean floor is covered in these nodules. Very valuable resource

Distribution of Nodules

Hydrogenous Sediments �Evaporites: Salts that precipitate out of sea water due to evaporation. As salinity increases, evaporites precipitate in the following order: Limestone-Calcium Carbonate Dolomite-Magnesium Calcium Carbonate Gypsum-Calcium Sulfate Halite-Sodium Chloride (salt)

Distribution of Marine Sediments