A Chromatographic Model for Water Quality Variations in the Aquia Aquifer (Maryland, Usa)

C. A. J. Appelo
Faculty of Earth Sciences, De Boelelaan 1085, 1081 HV Amsterdam, NL

Abstract: Flushing of marine sediments with fresh water will induce a chromatographic pattern of the cations which are displaced from the exchange complex. Upstream from the salt/fresh water boundary, a sequence of Na+, K+, Mg2+ and lastly Ca2+ dominated water is expected (Ca2+ is the displacing cation; HCO3− is the major anion). This sequence is present in the Aquia aquifer. Field data from this aquifer have been modeled with a 1D geochemical transport model to satisfactory agreement. The upper 30 miles of the aquifer must have been flushed about 8 times under the model conditions, which means that the now observed chromatographic pattern can have been established in 100 ka.

Mineralogical Magazine; August 1994 v. 58A; no. 1; p. 23-24; DOI: 10.1180/minmag.1994.58A.1.15
© 1994, The Mineralogical Society
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