Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Sedimentary Rocks Written by Denise Ulrich, DSD Writing Committee ©Davis School District Farmington, Utah 2012-2013 2 The Big Sandwich Sedimentary rock is made of bits and pieces of rock. The pieces have been broken off of other rocks over time by wind, water or ice. These pieces of rock are called sediments. The sediment is moved from place to place and settles into layers. The layers become pressed together over millions of years. It’s kind of like nature’s own giant sandwich! Layers of sedimentary rock 3 How Sedimentary Rock Is Formed Wind, water or ice can wear down a large rock or side of a mountain, creating sediments. This process is called weathering. Then running water, such as streams or rivers, rushes by and picks up the sediments. The sediments are carried to a new place such as the bottom of a lake or ocean. As the sediments settle on the floor of the lake or ocean, a layer is created. Water carries and leaves sediments in layers 4 Over millions and millions of years, new and different layers of sediments are brought to the same spot in the same way. The layers of sediments stack on top of each other. The pieces of rock are pressed together by the weight from the sea and the many layers above. This is how sedimentary rock is formed. A rock formation in Utah made from sedimentary rock How People Use Sedimentary Rocks You may use sedimentary rock and not even know it. Coal is a sedimentary rock that is burned to create energy for electricity to 5 light our homes and schools. Sedimentary rocks, such as sandstone or limestone, are used as stones for large buildings. Clay is mixed with sand and used to Coal make bricks for houses and other buildings. Limestone is also used in our roads, and is cooked to make cement for sidewalks and driveways. During winter storms, people use rock salt to break down the ice on roads and walkways. Sandstone Limestone 6 Glossary sand- loose grains made up of broken pieces of rock sedimentary rock- rock formed in layers from sediment sediments- pieces of rock or sand that are deposited by wind, water, or ice weathering- the breaking down of rocks into smaller pieces called sediments 7