‘An aquifer is best described as a saturated permeable geologic unit that can transmit significant quantities of water under ordinary hydraulic gradients’??’It is used to refer to individual geologic layer, to complete geologic formation, and even to groups of geologic formations’ .
- Freeze, R.A., and Cherry, J.A. 1979. Groundwater. Prentice-Hall, Inc., Eaglewood Cliffs, N.J.., pg. 47.