Sediment (A) may someday become a clastic rock (B) if compacted and cemented together.
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(A) courtesy of Bruce Molnia, Terra and (B) courtesy of Martin Miller, University of Oregon

Step 4: Turning a Pile of Sediment into Solid Rock!

Sediment is not a sedimentary rock unless the sediments become stuck together. The material that holds sediment together into a rock is called cement. It is made of mineral crystals. Cement forms when seawater or groundwater travels through the empty spaces between sediment and leaves mineral crystals behind.

A pile of sediment becomes a sedimentary rock more quickly when it is buried deep underground. This makes the sediment grains become squished closely together. However, turning a pile of sediment into solid rock takes a long time. It can take even take hundreds of thousands of years.

Last modified August 25, 2003 by Lisa Gardiner.

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