Carbonate ro Carbonate rockscks

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Carbonate rocks are composed of two minerals

Calcite CaCO3 Dolomite Ca Mg (CO3 ) The principal constituents of limestones ar

e 1. Allochemical components (ooids, biocla sts, peloids and intraclasts) 2 . Micrite (microcrystalline calcite: refers t

o a crystal size less than 5 um) 3. Sparite (sparry calcite; refers to crystal

5s of um or more in diameter)

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Dunham classification of limestone

Carbonate rocks Carbonate rocksOoid GrainstoneOoid Grainstone

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Carbonate rocks Carbonate rocksOoid PackstoneOoid Packstone

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Carbonate rocks Carbonate rocksBioclast PackstoneBioclast Packstone

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Carbonate rocks Carbonate rocksBioclast WackstoneBioclast Wackstone

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Carbonate rocks Carbonate rocksIntraclast GrainstoneIntraclast Grainstone

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Carbonate rocks Carbonate rocksPeloid GrainstonePeloid Grainstone

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Carbonate rocks Carbonate rocksCarbonate MudstoneCarbonate Mudstone

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Carbonate rocks Carbonate rocksDolomitic limestoneDolomitic limestone(The original sediment is a peloidal packstone)(The original sediment is a peloidal packstone)

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The matrix have been replaced by dolomite, showing its characteristic euhedral rhombic shape

Carbonate rocks Carbonate rocksDolomitic limeatoneDolomitic limeatone

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A limestone sec tion which has

been treated wi th Alizarine Red

S. Calcite showi ng shades of pi nk, red, and bro wn. The dolomit

e is colorless to grey and appea

rs to be replacin g matrix and/or

cement.

Carbonate rocks Carbonate rocksDolomite rock or dolostoneDolomite rock or dolostone

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Dolomitic carbonate are classified according to their dolomite content:

dolomite

0-10% Limestone

10-50% dolomitic limestone

50-90% calcitic dolomite

90-100% dolomite

Carbonate rocks Carbonate rocks

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THE END