Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock.
Clay is a finely-grained natural rock or soil material that combines one or more clay minerals with possible traces of quartz (SiO2), metal oxides (Al2O3, MgO etc.) and organic matter.
A concretion is a hard, compact mass of matter formed by the precipitation of mineral cement within the spaces between particles, and is found in sedimentary rock or soil.
In geology, fissility is the ability or tendency of a rock to split along flat planes of weakness (“parting surfaces”).
Mud is a liquid or semi-liquid mixture of water and any combination of different kinds of soil (loam, silt, and clay).
Mudrocks are a class of fine grained siliciclastic sedimentary rocks.
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds.
Particle size is a notion introduced for comparing dimensions of solid particles (flecks), liquid particles (droplets), or gaseous particles (bubbles).
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) mineral particles or rock fragments.
Sedimentary rocks are types of rock that are formed by the deposition and subsequent cementation of that material at the Earth's surface and within bodies of water.
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.
Silt is granular material of a size between sand and clay, whose mineral origin is quartz and feldspar.
In geology and related fields, a stratum (plural: strata) is a layer of sedimentary rock or soil, or igneous rock that were formed at the Earth's surface, with internally consistent characteristics that distinguish it from other layers.
Weathering is the breaking down of rocks, soil, and minerals as well as wood and artificial materials through contact with the Earth's atmosphere, water, and biological organisms.