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ตารางที่ 4.2 ตารางการจำแนกหินตะกอน (Dearman, 1991)

CHEMICAL/
DETRITAL SEDIMENTARY GENETIC GROUP
ORGANIC

Bedded Usual structure

Salts,
Grains of rock, quartz, At least 50% of grains Carbonates,
Composition
feldspar and clay minerals are of carbonate Silica
Carboneceous

Grains are of Saline rock: Very
coarse-
Rudaceous rock fragment Calcirudite Halite grained 60
Rounded grains:

Anhydrite
conglomerate
Gypsum Coarse-
grained

Angular grains: breccia 2
Arenaceous Grains are mainly Calarenite Medium-
mineral fragments
grained
Sandstone: grain are

mainly mineral fragments Limestone (undifferntiated) Calcreous rocks: 0.006 Predominant grain size (mm)
Siltstone: Limestone
50% fine Calcisiltite Dolomite Fine-
Agilliceous or Lutaceous Shale: particles Marlstone Chalk Siliceous rocks: Very fine- 0.002
grained
grained
Mudstone
Claystone:

Fissile

50% very

mudstone
fine-fine
grained Calcilutite Chert grained
Flint
particles Carbonaceous
rock:
Glassy
Lignite Amorphous
Coal