Sedimentary Rock (pg.30) Strata Rock that formed through a sequence of processes: weathering, erosion, deposition, compaction and cementation. weathering: effects of freezing & thawing, plant roots, acid and other forces on rock Erosion: the process by which running water, wind, ice carry away bits of broken rock Sediments come from weathering and erosion of igneous and metamorphic rock – even other sedimentary rock Rock fragments – called sediment, make up sedimentary rock (pg. 37) The layers of sedimentary rock New layers of sediment are deposited and compressed – compacted Minerals dissolve into natural glue i.e. the Grand Canyon

Composition of Sedimentary Rock Clastic Chemical Classified by the way it forms 3 main catagories Clastic Chemical Organic Made from the fragments of other rocks & minerals Fragments in clastic influence the names i.e. sandstone, siltstone Forms solutions of minerals and water i.e. Limestone is calcium carbonate – or calcite that is crystallized with sea water

Sedimentary Rock Structures Organic Sedimentary Rock Structures Most limestone forms from remains of animals that once lived in the ocean Shells or skeletons (calcium carbonate) Fossils are the remains or traces of plants or animals preserved in sedimentary rock Fossils give us information about ancient life forms The way the rock is formed Tells you a lot about the sedimentary rock

Stratification Layering of the rock Different depending on size, kind & color of sediment How fast the sediment is deposited also effects the stratification Can be record of wind and water waves