SEDIMENTARY ROCK

Mod E. U.3 L.3

Definition•Rock that forms when sediments are compacted and cemented together

Sedimentary Rock Layers

Formation (processes)•Weathering and erosion break down existing rock into sediment.

•Sediment is deposited in layers called strata

(Think Grand Canyon)

•Rocks get compacted and cemented

- compaction – due to pressure

- cementation – glue together

Three types:1. Clastic, 2. Organic, and 3. Chemical

1. Clastic

Classified by texture• Fine grained e.g. Shale (from

mud)• Medium –grained e.g.

Sandstone (from sand)• Coarse-grained e.g.

Conglomerate (from pebbles)

Shale - Fine grained

Sand stone - fine to medium grained

Breccia

Conglomerate

Coarse-grained

2. Organic •Sediment made up of remains of living organisms

•Shells, fossils, coal

Coquina

Chalk: A fine-grained, light-colored limestone formed from the calcium carbonate skeletal remains of tiny marine organisms.

Coal

3. Chemical•Minerals dissolved in water are crystallized when water evaporates

e.g.Limestone: calcium carbonate or calcite

Limestone

Limestone

Rock Salt or "halite" is a chemical sedimentary rock - forms from the evaporation of ocean or saline lake waters.

Sedimentary rocks formed as chemical precipitates.

 Name of Rock

 Precipitate Type

 Halite  Sodium Chloride

 Gypsum  Calcium sulfate

 Silcretes  Silica

 Limestone  Calcium Carbonate

 Dolomite  Calcium Magnesium Carbonate

Halite Limestone

Dolomite Chalk

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