In coastal aquifers, lighter fresh water lies above a wedge of more dense salt water, and is separated from it by a mobile transition zone. If aquifers are pumped at rates exceeding their natural capacity to transmit water, seawater is drawn into the system to maintain the regional groundwater balance. See Qahman and Larabi (2006) Hydrogeol. J. 14, 5 on Gaza.
Subjects: Earth Sciences and Geography.