SEDIMENTARY ROCKS

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SEDIMENTARY ROCKS
CARBONATES
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
I Color II Texture gr. size, sorting,
roundness III Structure IV Allochemical
constituents V Orthochemical
constituents VI Name
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
I Color - little value II Texture gr.
size, sorting, roundness III Structure IV
Allochemical constituents V Orthochemical
constituents VI Name
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
I Color II Texture III Structure IV
Allochemical constituents V Orthochemical
constituents VI Name
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
II Texture gr. size allochems treated
like clasts orthochems like igneous rx sorting
roundess fairly meaningless packing
very important (see classification below)
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
I Color II Texture gr. size, sorting,
roundness III Structure IV Allochemical
constituents V Orthochemical
constituents VI Name
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
III Structure
mostly growth structures stromatolites, mounds
and reefs also dunes, ripples, x-bedding
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
I Color II Texture gr. size, sorting,
roundness III Structure IV Allochemical
constituents V Orthochemical
constituents VI Name
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
IV Allochemical constituents fossils pel
oids ooids limeclasts V Orthochemical
constituents microxtalline calcite (micrite)
clay to silt-size MUD originates as
disarticulated algal material coarsely xtalline
calcite (sparry calcite or sparite)
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
Terrigenous detritus (5 average)

chert quartz, clays minerals
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SEDIMENTARY ROCKS
Texture, structure and composition
Authigenic

Chert 2 origins detrital (minor) intrabasinal
xtallization of amorphous silica from SiO2
shells a) sponges (Cambrian present) b)
radiolaria (Ordovician present) c) diatoms
(Jurassic present) most abundant now
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SEDIMENTARY ROCKS
Texture, structure and composition
Form sheet for sedimentary rocks
I Color II Texture gr. size, sorting,
roundness III Structure IV Allochemical
constituents V Orthochemical
constituents VI Name
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SEDIMENTARY ROCKS
Carbonate Classifications
Dunhams classification
Grain supported
Original components not bound together during
depostion
Original components bound together during
deposition
Lacks mud, grain-supported
Contains mud
Mud supported
lt 10 grains
gt 10 grains
Mudstone
Packstone
Wackestone
Grainstone
Boundstone
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SEDIMENTARY ROCKS
Carbonate Classifications
Dunhams classification
Grain supported
Original components not bound together during
depostion
Original components bound together during
deposition
Lacks mud, grain-supported
Contains mud
Mud supported
lt 10 grains
gt 10 grains
Mudstone
Packstone
Wackestone
Grainstone
Boundstone
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SEDIMENTARY ROCKS
Carbonate Classifications
Dunhams classification
Grain supported
Original components not bound together during
depostion
Original components bound together during
deposition
Lacks mud, grain-supported
Contains mud
Mud supported
lt 10 grains
gt 10 grains
Mudstone
Packstone
Wackestone
Grainstone
Boundstone
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SEDIMENTARY ROCKS
Carbonate Classifications
Dunhams classification
Grain supported
Original components not bound together during
depostion
Original components bound together during
deposition
Lacks mud, grain-supported
Contains mud
Mud supported
lt 10 grains
gt 10 grains
Mudstone
Packstone
Wackestone
Grainstone
Boundstone
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SEDIMENTARY ROCKS
Carbonate Classifications
Dunhams classification
Grain supported
Original components not bound together during
depostion
Original components bound together during
deposition
Lacks mud, grain-supported
Contains mud
Mud supported
lt 10 grains
gt 10 grains
Mudstone
Packstone
Wackestone
Grainstone
Boundstone
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SEDIMENTARY ROCKS
Carbonate Classifications
Folks
Allochemical rocks Orthochemical rocks Reef
rocks allochems cement
sparry calcite micrite Intraclasts
intrasparite intramicrite
sparite biolithite Ooids
oosparite oomicrite Fossils
biosparite biomicrite Pellets
pelsparite pelmicrite