Sedimentary rocks are formed from material that has settled into layers. These layers have been squeezed together so much that they have hardened into rock.
Some classifications of sedimentary rocks are the following:
Clastic: Old pieces of rock cemented together by minerals such as calcite
Crystalline: Made of crystals that formed from minerals being deposited from water.
Organic: Made from pieces of organic materials, such as shells
Picture by Kimily
Fun Stuff: To understand sedimentary layers, take a glass jar and fill it about one-third full with rocks, pebbles, sand, and soil. Finish filling the jar by pouring water into it. Put the lid on it and shake it, then set it down. Take a piece of paper and write down a prediction of what you think will happen to the contents of the jar. Let the jar sit for a while, then look at it and see what happened. Record your results!
