Sedimentary Rocks

THE PRODUCTION OF SEDIMENTARY ROCKS

Sedimentary rocks are rocks formed from layers of sediment such as sand, mud, small stones, and dead plants or animals. Over millions of years, these layers are pressed together and become solid rock. Sedimentary rocks usually form in places where water is present, like rivers, lakes, and seas.

Main features:

• Made in layers called strata

• Often contain fossils

• Formed by compaction and cementation of sediments

Examples:

• Sandstone

• Limestone

• Shale

How they form:

1. Rocks break down through weathering.

2. The pieces are carried by water or wind.

3. Sediment settles in layers.

4. Pressure and minerals turn the layers into rock.