Книга: Aquifer: Permeability (Earth Sciences), Water, Gravel, Sand, Silt, Clay, Water Well, Groundwater, Hydrogeology, Water Table, Water Content, Hydraulic Conductivity, ... Specific Storage, Saltwater Intrusion

An aquifer is an underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, silt, or clay) from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology. Related terms include: an aquitard, which is an impermeable layer along an aquifer, and an aquiclude (or aquifuge), which is a solid, impermeable area underlying or overlying an aquifer. The surface of saturated material in an aquifer is known as the water table