2How sedimentary rocks form… Wind, water, ice, sunlight, and gravity cause rocks to weather into sediments.These sediments are moved from one location to another by the process of erosion.Erosion: The movement of the material from one place to another
3Formation of Sedimentary Rocks The sediments are eventually deposited on to older layers and form new ones.The sediments become compacted and dissolved minerals separate from water and form a natural cement—Lithification.Sedimentary rocks are formed
4Strata and stratification Layers of rockSTRATIFICATIONprocess in which sedimentary rocks are arranged in layers
5How are were the stripes formed? Wind blew over thousands of yearsCarried mineral/rock fragments, “sand” to ocean floors, lakes riversThe sand mixes with quartz or calcite.Pressure over time causes them to become rock
6How are the Stripes Formed? But not all sand is the same!Over millions of years, smaller grains separated from the larger grains and were layered on the bottome
7Petra Why do you think there are so many colors in the stone? Can you describe the pattern on this structure?Does this structure support the idea that layers of sediments piled on top of each other and exposed to heat and pressure form sedimentary rock?
8Organic sedimentary rocks Form from remains or fossils of once living things.EXAMPLE: limestone, coalCOAL----Forms underground when partially decomposed plant material is buried beneath sediment and is changed into coal the pressure from layers above.This process takes millions for years.Non-renewable fossil fuel
10Clastic sedimentary rocks Made from fragments (sediments) of rocks that are cemented together by minerals .They are classified according to the size of the fragments.EXAMPLES: conglomerate, sandstone, siltstone, shale