Sedimentary Rocks Facts
Sedimentary rocks are types of rock that are formed by the deposition of material at the Earth’s surface and within bodies of water.
Sedimentary rocks have also been found on Mars.
Sedimentary rocks are formed by sediment that is deposited over time, usually as layers at the bottom of lakes and oceans.
Sedimentary rocks forms layers called strata which can often be seen in exposed cliffs.
Examples of sedimentary rocks include limestone, sandstone, mudstone, greywacke, chalk, coal, claystone and flint.
Limestone forms the metamorphic rock marble when subjected to extreme heat and pressure over time (metamorphism).Limestone is rock containing many fossils and made of calcium carbonate and/or very tiny shells.
Sandstone forms the metamorphic rock quartzite.Sandstone is a soft stone made when sand grains cement together. Sometimes the sandstone is deposited in layers of different colored sand.
Mudstone forms the metamorphic rock slate.
Shale is clay that has been hardened and turned into rock. It often breaks apart in large flat sections.
Chalk is a soft, white form of limestone.
Flint is a hard, sedimentary form of the mineral quartz.
Gypsum is a common white or colourless mineral used to make cements and plasters.
Sedimentary rocks are very important in helping us to find clues about the Earth’s past
Table salt actually comes from a chemical sedimentary rock called halite.
Sedimentary Rocks Vocabulary
Sediment: debris of weathered rocks and minerals, as well as dead plants and animals
Lithify: to change sediment to stone
Decay: rot, decompose
Compress: when something is pressed to become dense and compact