Groundwater quality in the Tertiary Ledo-Paniselian aquifer in Belgium as a result of fresh-water intrusion into sediments in chemical equilibrium with the sea
Walraevens, K.; Lebbe, L. (1989). Groundwater quality in the Tertiary Ledo-Paniselian aquifer in Belgium as a result of fresh-water intrusion into sediments in chemical equilibrium with the sea. Natuurwet. Tijdschr. 70(1-4): 30-44
In: Natuurwetenschappelijk Tijdschrift. L. Walschot/Natuur- en Geneeskundige Vennootschap: Gent. ISSN 0770-1748, meer
Ook verschenen in:De Breuck, W.; Walschot, L. (Ed.) (1989). Proceedings of the 10th Salt-Water Intrusion Meeting Ghent (Belgium), 16-20 May 1988. Natuurwetenschappelijk Tijdschrift, 70(1-4). Natuurwetenschappelijk Tijdschrift: Gent. 408 pp., meer
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| Trefwoorden |
Geological time > Phanerozoic > Geological time > Cenozoic > Tertiary
Water > Ground water
Water quality
België, Belgische kust [Marine Regions]; België, Vlaanderen [Marine Regions]
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| Abstract |
The present distribution of the groundwater quality in the semi-confined Ledo-Paniselian aquifer is the result of the marine conditions prevailing in the sediments before the last regression. These marine conditions, evident in a marine pore solution and in a marine-cations adsorption on the clay-minerals surfaces, are being gradually expelled by infiltrating fresh water. First the marine pore solution has been diluted and then cation exchange started between the fresh water and the clay particles. In the course of time groundwaters of successively different qualities where thus leaking out from the overlying Bartonian clay into the Ledo-Paniselian aquifer. The resulting groundwater types are found in consecutive zones in the aquifer. The hydrochemistry of these different zones is described according to the classification of STUYFZAND (1986), the use of which allowed for examination of the different processes taking place in the clay layers during the expulsion of marine features. The distribution of the different groundwater types in the Ledo-Paniselian aquifer may be correlated with the calculated natural groundwater flow. Until now, this distribution, surveyed on a regional scale, is not influenced by the heavy pumpings of the last years, which have changed the groundwater direction and velocity completely. |
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