Más contenido relacionado La actualidad más candente (20) Similar a Marine Sediments Types (Detailed) (20) Marine Sediments Types (Detailed)1. Diatoms
Photosynthetic
algae
Diatomaceous
earth
Radiolarians
Protozoans
Use external
food
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2. Tests from diatoms
and radiolarians
generate siliceous
ooze.
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3. Coccolithophores
Also called
nannoplankton
Photosynthetic algae
Coccoliths –
individual plates
from dead organism
Rock chalk
Lithified coccolith-
rich ooze
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4. Foraminifera
Protozoans
Use external
food
Calcareous ooze
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5. Depends on three processes:
Productivity
Destruction
Dilution
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6. Dominated by lithogenous sediment, may
contain biogenous sediment
Carbonate Deposits
Carbonate minerals containing carbon trioxide (CO3 )
Marine carbonates primarily limestone – CaCO3
Most limestones contain fossil shells
Suggests biogenous origin
Ancient marine carbonates constitute 25% of all
sedimentary rocks on Earth.
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7. Stromatolites
Fine layers of
carbonate
Warm, shallow-
ocean, high salinity
Cyanobacteria
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10. Minerals precipitate directly from
seawater
Manganese nodules
Phosphates
Carbonates
Metal sulfides
Small proportion of marine
sediments
Distributed in diverse environments
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11. Fist-sized lumps of
manganese, iron,
and other metals
Very slow
accumulation rates
Grows ~1 centimeter
over several million
years
Many commercial
uses
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12. Phosphates
Phosphorus-bearing
Occur beneath areas in surface ocean of very high
biological productivity
Economically useful as fertilizer
Carbonates
Aragonite and calcite
Oolites
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13. Metal sulfides
Contain:
Iron
Nickel
Copper
Zinc
Silver
Other metals
Associated with hydrothermal vents
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14. Evaporites
Minerals that
form when
seawater
evaporates
Restricted open
ocean circulation
High
evaporation rates
Halite (common
table salt) and
gypsum
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15. Macroscopic
meteor debris
Microscopic iron-
nickel and silicate
spherules (small
globular masses)
Tektites
Space dust
Overall,
insignificant
proportion of
marine sediments
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17. Energy resources
Petroleum
Mainly from continental shelves
Gas hydrates
Sand and gravel (including tin, gold, and so
on)
Evaporative salts
Phosphorite
Manganese nodules and crusts
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