Confined aquifer
"An aquifer whose upper and lower, boundary is de ned by a layer of natural material that does not transmit water readily. Water is “con ned” under pressure similar to water in a pipeline. Drilling a well into this type of aquifer is analogous to puncturing a pressurized pipeline. In some areas con ned aquifers produce water without pumps ( owing artesian well)." (U.S. Geological Survey, 2019)
Sources
U.S. Geological Survey (USGS). "Water Science Glossary Terms". USGS Water Science School. (2019). Link: https://water.usgs.gov/edu/dictionary.html#W