Sedimentary Rocks

Sedimentary rocks are made of sediment that has settled to the bottom of water and stuck together. The sediment may include items like mud, clay, soil, leaves, animals, plants, pebbles, and sand. As sediment piles up, the pressure from the top layers forms the lower layers into rock.

If plants or animals are in the sediment, their imprint may remain in the rock, making fossils. Different materials that settle to the bottom have different colors. For that reason, many sedimentary rocks have layers of color.

Sources:

Anderson, Alan, et. al. Geology Crafts for Kids: 50 Nifty Projects to Explore the Marvels of Planet Earth. New York: Sterling Publishing Co., Inc., 1996.

Blobaum, Cindy. Geology Rocks! 50 Hands-On Activities to Explore the Earth. Charlotte, VT: Williamson Publishing, 1999.

Science and Technology for Children. Rocks and Minerals. Burlington, NC: Carolina Biological Supply Company, 1997.