Sedimentary Rocks

 Sedimentary Rocks

Most sedimentary rocks are composed of the weathered rocks fragments and particles called sediments.  Sedimentary rocks usually form from the burial of sediments that are compacted, and cemented under layers of other sediments. 
The Grand Canyon

Sedimentary rocks are mainly caused by the gradual weathering and erosion of pre-existing rock and organic material.  These rocks are broken down into smaller sediments that may be carried away by wind, water, ice, and gravity.  


Sedimentary rock cliffs. Image credit: Leene/Shutterstock.com

The material that is transported by the process of erosion will finally be deposited and buried at a new location.  Often the buried sediments will be cemented together under the pressure of overlying sediments.   The process of burial causes the buried sediments to lose water and the dissolved minerals in the pore spaces, between the sediments, act as a cement that hold the solid sediments together.

Location: Queens, NY, USA

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