Aquiclude: A geologic formation which may contain water but does not transmit it.
a formation which, although porous and capable of absorbing water slowly, will not transmit water fast enough to furnish an appreciable supply for a well or a spring.
A saturated geologic unit that is incapable of transmitting significant quantities of water under ordinary hydraulic gradients.
: An outdated term for a geologic layer of very low permeability located so that it forms an upper or lower boundary to a groundwater flow system. Aquitard or Confining Layer are preferred terms.
Aquiclude: rock formations impermeable to groundwater.
Aquifer: an underground layer of sand or rock that contains usable water. Can be unconfined (down to the first impervious rock layer) or confined (between the first and the second layers).
confined groundwater Groundwater held under an or an aquifuge, if the pressure is positive it is called artesian.
confining bed ...
See also: Treatment, Biological, Structure, Air, Sediment