An aquifer is an underground layer of rock that holds groundwater. Groundwater is rain or melted snow that has seeped into the ground and is held there. Aquifers are filled slowly. For this reason, aquifers can dry up when people drain them faster than they can be refilled—a process called aquifer depletion. Aquifers can be drained by man-made wells or they can flow out naturally in springs.
an underground layer of rock or earth which holds groundwater.
process by which people pump more water out of aquifers than can be replaced by rain or snow.
water found in an aquifer.
natural substance composed of solid mineral matter.
to slowly flow through a border.
precipitation made of ice crystals.
small flow of water flowing naturally from an underground water source.
a hole drilled in the Earth to obtain a liquid or gaseous substance.