Extraction of fresh water from a groundwater source or surface, permanently or temporarily, and conveyed to the place of use. Water abstractions include all activities related levies generated by agriculture, industry (including energy), the supply of drinking water, or other (mineral spring authorized, production artificial snow).
Rechercher un terme
Portion of the Earth's crust on which has been deposited, or still is depositing, many layers of sediment, produced by the alteration of preexisting rocks. Over time, significant accumulation of sediments causes the depression of the deposition zone, and allows the addition of new layers, creating a sedimentary basin.
According to the hydro-geological meaning, a water volume supplying an aquifer over a given time. Rainfalls are mainly recharging groundwater. Unconfined groundwaters are recharged rather fast at each rainfall event. The rise in water levels and rainfall events are observed on a piezometric curve.
Continuous or discontinuous geological formation, containing temporary or permanent water that can be mobilized. It consists of permeable rock (porous or fractured formation) able to provide water naturally or though exploitation (drainage, pumping).
Elevation defined either in NGF level (French levelling network) or in relative depth. The NGF level, established under the control of the National Geographic Institute (IGN), is the reference. NGF can indeed express altitudes in one and unique reference system, i.e. as compared to the same and unique fundamental point (or "origin-zero" or point zero). The "0" level is the average sea level in Marseilles. This point is used to determine the altitude of any other point. The elevation of the piezometric record can also be expressed in relative depth with respect to the benchmark of the