Sedimentary Rocks Sedimentary rocks. Formation of Sedimentary Rocks Most sedimentary rocks are...

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Sedimentar y Rocks Sedimentary rocks

Transcript of Sedimentary Rocks Sedimentary rocks. Formation of Sedimentary Rocks Most sedimentary rocks are...

Sedimentary Rocks

Sedimentary rocks

Formation of Sedimentary Rocks

Most sedimentary rocks are composed… ADD HERE

The sediments that are weathered from older rock are transported to new locations by an erosional agent –

like streams or glaciers.

Most of these sediments will eventually be deposited as horizontal beds in large bodies of water. Over

time, these deposited sediments will transform into sedimentary rock through a number of different

processes including:

-- COMPACTION-- CEMENTATION

-- CHEMICAL ACTION-- ORGANIC PROCESSES

Compaction and Cementation

Many sediments exposed to movements of the Earth and/or the weight of overlying large bodies of water over long periods of time are “compressed” together – reducing pore space and

volume between sediments or clasts. This is known as compaction.

Most sediments that experience compaction also experience cementation.

Cementation occurs when dissolved minerals in water precipitate in the pore space between sediments “cementing” them together.

Shale is formed from the… ADD

HERE

Sandstone is formed from

the… ADD HERE

Clastic Sedimentary Rocks

Chemical Action

Water at Earth’s surface contains many soluble minerals (minerals dissolved in water).

When water evaporates, the minerals in solution will precipitate out as a solid, crystalline form known as an evaporite. Evaporites

are composed of one mineral and are non-clastic. Non-clastic sedimentary rocks are rocks… ADD HERE

Evaporites are also called chemical sedimentary rock.

A B C

Examples of chemical sedimentary rocks (evaporites) include: rock salt (A), rock gypsum (B), and dolostone (C).

Non-Clastic Sedimentary Rocks

Organic Processes Bioclastic Sedimentary Rocks

Some sedimentary rocks are formed from the organic processes of living things. These rocks are often referred to as… ADD HERE

Bioclastic sedimentary rocks are those made by… ADD HERE

Bituminous Coal is compacted

remains of plants.

Fossiliferous Limestone is

formed by the compaction and cementation of shell fragments.

Distinguishing Features of Sedimentary Rocks

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Distinguishing Features of Sedimentary Rocks

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6. Some sedimentary rock preserves features that may

appear… ADD HERE

Identifying Sedimentary Rocks

RT = Pg. 7

The clasts within a sedimentary rock measure .002 cm in diameter. What is

the name of the rock?