sedimentid

Sedimentid refers to a broad category of sedimentary rocks that are classified based on their grain size. This classification system, commonly used in geology, distinguishes between different types of clastic sedimentary rocks. The primary factor determining a rock's sedimentid classification is the average diameter of the individual mineral or rock fragments that make up the rock.

The coarsest sedimentids are conglomerates and breccias. Conglomerates consist of rounded pebbles and cobbles, indicating that the sediment has been transported a significant distance, allowing for abrasion. Breccias, on the other hand, are composed of angular fragments, suggesting less transport or deposition closer to the source.

Sandstones are the next largest sedimentid, formed from sand-sized grains, typically between 0.0625 and 2 millimeters in diameter. These grains can be composed of quartz, feldspar, or rock fragments. Siltstones are composed of silt-sized particles, which are finer than sand but coarser than clay, ranging from 0.0039 to 0.0625 millimeters.

The finest sedimentids are shales and mudstones, both made up of clay-sized particles, which are less than 0.0039 millimeters in diameter. Shales are characterized by their fissility, meaning they split into thin layers, while mudstones are typically massive and lack this layering. The specific sedimentid is determined by the dominant grain size present in the rock.