What term refers to a layer that restricts groundwater movement?

The term that refers to a layer that restricts groundwater movement is "Confining Unit." A confining unit is a geological layer, typically composed of materials like clay or silt, that has low permeability. This low permeability inhibits the flow of water, effectively separating different aquifer systems and controlling the movement of groundwater within those systems. This characteristic is essential for understanding groundwater dynamics, as it can influence the pressure and availability of both confined and unconfined aquifers.

Recharge areas, on the other hand, are regions where water infiltrates the ground to replenish an aquifer, and unconfined aquifers are groundwater systems that are not overlain by a confining layer, allowing water to flow freely. Artesian wells tap into confined aquifers, where groundwater is under pressure, but the defining feature of a confining unit is its role in restricting water movement.