2Mechanical (Physical) WeatheringThe process that breaks down rocks at Earth’s surface into sediments.Mechanical (Physical)Freezing and thawingRelease of pressureGrowth of PlantsActions of AnimalsAbrasion- grinding away rock by particles of rock.ChemicalChemical ChangesWaterOxygenCarbon DioxideLiving OrganismsAcid Rain
3ErosionThe process by which wind,water,ice,or gravity Running water or wind loosen and move rock fragments (sediments).*Moving water * winds * gravity
4DepositionProcess by which particles (sediments) settle out of water or the wind carrying it.Sediments- fragments and particles of rocks, and pieces of living things such as shells, bones, leaves and stems. (The pieces from living things form fossils.
5CompactionThe process that presses rocks together due to gravity and the weight of overlying layers.Loose LayersLayers build and become heavier pressing down.More layers form and add weight, which presses down and compacts the rock.Creates visible layers
6CementationThe process in which dissolved minerals crystallize and glue particles of sediment together.Occurs during compaction.Dissolved minerals fill in the spaces between sediments.
7Clastic RocksRock fragments are squeezed together. Grouped by the size of the fragments.Size- from extremely small clay size to boulders.ShaleForms from tiny particles of clay.Very thin layersNo cement is needed.Shale is smooth and splits easily into pieces.SandstoneForms from sand on beaches, the ocean floor, in river beds and sand dunes.Compaction and cementation of sand.Mostly made of quartzAbsorbs water easilyConglomerateForms from a mixture of rock fragments of different sizes.Conglomerate- has rounded edges.Breccia- sharp edges
8Organic RocksForms where the remains of plants and animals are deposited in thick layers.CoalForms from the remains of swamp plants buried in water.The weight of each layer squeezes the decaying plants.Millions of years later, coal is formed.LimestoneForm from the hard shells of living things. (Calcite)Layers of shells build up.Pressure squeezes the shells together.Dissolved calcite cements the shells together.Chalk
9Chemical RocksForms when minerals that are dissolved in solution crystallize.Rock SaltMade of haliteForms from evaporation.Gypsumformed from evaporation.LimestoneCan form when dissolved calcite comes out of solution.
10Uses of Sed. RocksSandstone and Limestone have been used for building materials for thousands of years.Easily cut into slabs.Limestone is used in cement.White House is built of Sandstone.