This document describes the various types of sediments found in marine environments. It discusses biogenic sediments like siliceous and calcareous ooze produced by organisms such as diatoms, radiolarians, coccolithophores, and foraminifera. It also describes lithogenous sediments, such as carbonate deposits, stromatolites, and chemical precipitates including manganese nodules, phosphates, and metal sulfides. Additionally, it discusses evaporites, meteoritic debris, and the economic resources obtained from marine sediments.

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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