glarea

Glarea is a term used in historical and Latin-influenced geological literature to denote coarse granular sediment, typically translated as gravel. In modern English geology, the word is uncommon; gravel remains the standard term for clastic sediment with particle sizes roughly 2 to 64 millimeters.

Glarea comprises clasts of various lithologies, usually larger than granules and smaller than cobbles, and may range from well-sorted to poorly sorted. Clean glarea contains little fines, resulting in relatively high porosity and permeability, whereas a muddy matrix reduces both.

Depositional environments associated with glarea include high-energy braided rivers, glacial outwash plains, alluvial fans, and channel lag deposits where finer material has been removed by transport. The texture and sorting of glarea reflect the transport history and energy of the depositional setting.

Although historically used as a general descriptor for gravel-like sediments, glarea is not a discrete mineral or mineralogical phase. It serves as a sedimentological term for describing texture and sedimentary environment, with gravel as the precise modern label.

Related topics include gravel, sedimentology, glacial outwash, and alluvial fans.