Sedimentary Rock

Sediment Different sizes of clasts are broken down through the many processes of erosion. They are then carried by wind, water, moving ice, and dropped or left in a new place in a process called deposition. Over time, layers of clasts become compacted and cemented together (also known as lithified) forming sedimentary rock.

Sediment The process of leaving material behind by wind, water, or moving ice in a process called deposition.

Sedimentary rock Rock created when different grain size particles (known as clasts) of Earth become compacted, cemented (lithification).

Grain size from largest to smallest Boulders Pebbles Gravel Sand Silt Clay

Types of Sedimentary rock I Clastic – coarse grained to fine grained Conglomerate Breccia Sandstone Siltstone also known as shale

Sedimentary - conglomerate Large grained Rounded pebbles or gravel compacted and cemented together are called…

Sedimentary - Breccias Large grained jagged edged pebbles or gravel compacted and cemented together are called…

Sedimentary - sandstone Small sand sized clasts Give a “gritty” texture to this stone called…

Sedimentary - siltstone Fine grained – smooth texture Siltstone stone is also called…

Sedimentary - shale Very fine almost no grain. Very smooth texture.

Types of Sedimentary rock II Organic – made from once living organisms. Coal Limestone

Sedimentary - organic Coal – made from the remains https://www.uky.edu/KGS/coal/coalform_download.htm Sedimentary - organic Coal – made from the remains of decayed plant and animal material. Peat- plant matter Lignite- brown coal/still some moisture present Bituminous- soft black coal/almost all moisture removed Anthracite – hardened black coal/ almost pure carbon/ no moisture.

Coal formation bituminous peat lignite anthracite

Sedimentary organic Limestone – begins as shells or calcium bearing animals or plants. These die and float to the bottom of the ocean or lake they inhabit. Eventually enough accumulates to create enough pressure to create limestone.

Sedimentary organic Limestone formation 1. Shells and bones and other organic matter settle To the ocean floor. 2. Over time, the accumulation builds enough to compress lower layers and the silica rich environment lithifies the pieces of broken debris forming fossiliferous limestone. The shell fragments are still visible.

Sedimentary organic Limestone formation 3. Eventually the fragment and debris are so interconnected and lithifies that the stone takes on a different characteristic and is called coquina where few if any fragments are visible. 4. Finally the compression and combined with lithification create a true limestone with no hint of the organic matter that created it. White, grey, red, brown, black in color depending on the type and amount of the differing organic matter that is lithified.

Sedimentary rock III Chemical sedimentary rock Evaporates Lime stone can also be formed through chemical process of evaporation. Uses of limestone Calcite Halite Formed when mineral rich water evaporated leaving the mineral behind to chrystalize.