Groundwater-rock interactions

Processes controlling nuclide distributions. The general equations for onedimensional advective transport along a groundwater flow path of groundwater constituents, and the incorporation of water/rock interactions, are given in such texts as Freeze and Cherry (1979). The equations can be applied to the distribution in groundwater of each isotope I with a molar concentration Iw and parent with Pw to obtain... 

There are four naturally occurring isotopes of Ra " " Ra (ti/2 = 5.8 a) and " Ra (3.7 d) in the Th series, (1600 a) in the series, and Ra (11.7 d) in the series (Table 1). The data for Ra are more limited, since it is generally present in low concentrations due to the low abundance of The differences in half lives and the connections across the different decay series have been used to infer a variety of groundwater and water-rock interaction features. For the short-lived Ra isotopes, the dominant input term to groundwater is recoil, rather than weathering, and steady state concentrations are often achieved (see Section 2.2). 

Patterson CG, Runnells DD. 1992. Dissolved gases in groundwater as indicators of redox conditions. Water-Rock Interaction, Proc Int Symp, 7th 1 517-520. 

Fig. 2.11. Configurations of reactive transport models of water-rock interaction in a system open to groundwater flow (a) linear domain in one dimension, (b) radial domain in one dimension, and (c) linear domain in two dimensions. Domains are divided into nodal blocks, within each of which the model solves for the distribution of chemical mass as it changes over time, in response to transport by the flowing groundwater. In each case, unreacted fluid enters the domain and reacted fluid leaves it.

The increased solute-loading in terrestrial waters is due to dissolution of minerals in rock, soil and overburden materials as rainwater infiltrates them. Groundwater experiences the largest degree of water-rock interaction and consequently has the highest average... 

Frape SK, Fritz P, McNutt RH (1984) Water-rock interaction and chemistry of groundwaters from the Canadian Shield, Geochim Cosmochim Acta 48 1617-1627 Freeman KH (2001) Isotopic biogeochemistry of marine organic carbon. Rev Miner Geochem 43 579-605... 

Harris, W.H. (1971) Groundwater-carbonate rock interactions, Barbados, W.l. Ph.D. dissertation, Brown Univ., Providence, R.I. 

The discussion on the application of dissolved ions as indicators of the rocks passed through by groundwater is of a generalized nature—to show the direction of hydrochemical thinking—and is useful in establishing the constrains needed to formulate phenomenological conceptual hydrological models (section 1.5). The topic of chemical water-rock interactions is discussed by Drever (1982), Erikson (1985), and Hem (1985). 

Chloride is unique as being most conservative among the common ions. Once it is introduced into the groundwater it stays in it, as there exists no water-rock interaction that can remove chlorine from groundwater. Bromide and lithium are similarly conservative, but their concentrations are low in fresh groundwater, and hence they are seldom analyzed. 

Answer 11.8 The Issy well pumps very old water. The 513C value, <513C = — 15%o, reveals no dilution of carbon isotopes occurred in the aquifer beyond the initial water-rock interactions. Hence, an initial groundwater 14C of 60pmc (at least) may be assumed, and the present value of 3.7 pmc indicates four half-lives have passed (reducing the 14C from 60pmc to 30, 15, 7, and 3.5 pmc respectively). Thus the water has an age of 5.730 x 4 = 23,000 years. 

Kroitoru, L., Carmi, I., and Mazor, E. (1987) Groundwater 14C activity as affected by initial water-rock interactions in a carbonatic terrain with deep water tables Judean Mountains, Israel. Ini. Symp. on the Use of Isotope Techniques in Water Resources Development, IAEA, Vienna, extended abstract, 134-136. 

Many different forms of models are utilized, usually dictated by the objectives of research. Conceptual models are the most fundamental. All of us have some kind of concept of water-rock interactions. For a groundwater interacting with the aquifer minerals during its evolution, one might conceive that most minerals would be undersaturated in the area of recharge but that some minerals (those that dissolve fastest) would become saturated at some point down gradient, having reached their equilibrium solubility... 

Johnson T. M. and DePaolo D. J. (1996) Reaction-transport models for radiocarbon in groundwater the effects of longitudinal dispersion and the use of Sr isotope ratios to correct for water-rock interaction. Water Resour. Res. 32, 2203-2212. 

Erape S. K., Bryant G., Durance P., Ropchan J. C., Doupe J., Blomqvist R., Nissinen P., and Kaija J. (1998) The source of stable chlorine isotopic signatures in groundwaters from crystalline shield rocks. In Proc. 9th Int. Symp. Water-Rock Interaction (eds. G. B. Arehart and J. R. Hulston). Taupo, New Zealand Balkema, Rotterdam, The Netherlands, pp. 223-226. 

Kamineni D. C., Gascoyne M., Melnyk T. W., Frape S. K., and Blomqvist R. (1992) Cl and Br in mafic and ultramafic rocks significance for the origin of salinity in groundwater. In Proc. 7th, Int. Symp. Water-Rock Interaction (eds. Y. K. Kharaka and A. S. Maest). Park City, UT Balkema, Rotterdam, The Netherlands, 801-804. 

Nordstrom D. K., Ball J. W., Donahoe R. J., and Whittemore D. (1989a) Groundwater chemistry and water-rock interactions at Stripa. Geochim. Cosmochim. Acta 53, 1727-1740. 

Waters containing 10-25 p.gL selenium may have a garlic odor, whereas waters containing 100-200 p,gL selenium also have an unpleasant taste. Groundwaters generally contain higher selenium concentrations than surface waters, because water-rock interactions have been more extensive (Frankenberger and Benson, 1994 Jacobs, 1989). 

NicolU H. B., Tineo A., Garcia J., Falcon C., and Merino M. (2001) Trace-element quality problems in groundwater from Tucuman, Argentina. Water—Rock Interaction. AA Balkema, Rotterdam, pp. 993—996. 

Characterization of natural colloids in groundwaters of El Berrocal, Spain. In Water-Rock Interaction... 

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