What is the definition of an aquifer?

An aquifer is best defined as permeable rock that contains or carries water. This is crucial because an aquifer acts as a natural underground reservoir, allowing water to flow through the rock or sediment, which is essential for replenishing freshwater supplies. The permeable nature of the rock or sediment means that it has spaces or pores that can be filled with water, making it possible for water to be stored and moved within the aquifer. This property is what distinguishes aquifers from other geological formations and is key to their function in the hydrological cycle and water supply systems.

In groundwater management, understanding the characteristics of aquifers helps in identifying sources of water for wells and assessing sustainability in water extraction practices. The other options do not accurately describe an aquifer’s characteristics or function.