The hydrochemical identification of groundwater flowing to the Bet She’an-Harod multiaquifer system (Lower Jordan Valley) by rare earth elements, yttrium, stable isotopes (H, O) and Tritium

doi:10.1016/j.apgeochem.2011.11.011

Applied Geochemistry

Volume 27, Issue 3, March 2012, Pages 703-714

https://doi.org/10.1016/j.apgeochem.2011.11.011 Get rights and content

Abstract

The Bet She’an and Harod Valleys in Israel are regional recipients and mixing zones for groundwater draining from a multiple aquifer system, which includes carbonate and basalt aquifers and deep-seated pressurized brines. The aquifers drain through two types of outlets, distinct and mixed. The latter type is mainly conditioned by the occurrence of fault-blocks related to the Jordan Rift system, which act as connecting media between the aquifers and facilitate interaquifer flow. Conjoint application of rare earth element distribution and water isotopes enables detection of the local areas replenishment by rainfall infiltration and, in connection with the position of wells or springs, the identification of groundwater flow paths. Once stationary equilibria are established changes of REY composition between REY in groundwater and their surface adsorption, are negligible. In areas with little soil coverage and vegetation even recharge over young Tertiary and diagenetic Cretaceous limestones is distinguishable by their REY distribution patterns. Groundwater recharged over Tertiary limestones show higher REY abundance and more significant Ce anomalies than those derived from the Cretaceous limestones. Weathering of alkali olivine basalts leads to REY patterns in groundwater depleted in the middle REE. The improved knowledge of the hydrological systems is thought to be useful for regional hydrogeological modeling and for designing rational water management schemes.

Highlights

► Recharge areas and flow-paths of water are detectable by conjoint analyses of stable isotopes and REY-pattern in groundwater. ► In semi-arid regions highly disturbed by faults in which intricate inter-aquifer flow occurs exercised method is worthwhile. ► A non-invasive system-knowledge is fundamental for smart water resources management. ► Identifying hydrogeological components is prerequisite do develop sustainable exploitation strategies. ► In areas with scarce groundwater but different societies the above items become highly politically.

Introduction

The rare earth elements (REE) La to Lu and Y (henceforth combined to REY) are ubiquitous and naturally occurring in all hydrological systems. In low-temperature aqueous systems REY behave non-conservatively unless strongly complexed as chelates (Möller et al., 2000) or strongly bound by natural organic matter (Johannesson et al., 2004). Redox changes, complexation and sorption by organic matter cause the REY distribution patterns to vary (Dia et al., 2000, Worral and Pearson, 2001, Tweed et al., 2006). REY distributions in groundwaters have been shown to reflect those of their aquifer rocks/sediments (Smedley, 1991, Johannesson et al., 1997a, Johannesson et al., 1997b, Johannesson et al., 1999, Johannesson et al., 2000, Takahashi et al., 2002, Möller et al., 2003) as long as limestones are involved. In sandstones (Möller et al., 2003), basalts (Paces et al., 2001) and granites (Möller et al., 1997), the REE patterns differ from those of the aquifer rocks because of incongruent dissolution of REY bearing minerals, coprecipitation of REY with alteration products and REY scavenging by Fe–oxyhydroxide. In such cases it takes a much longer time until saturation of the groundwater is achieved. Apart from carbonates and sulfates, REY are released from REY-bearing accessory minerals by the first water/rock interaction in the recharge area. Both aspects together qualify REY patterns as indicators of the lithology of the recharge area, whereas the major element chemistry characterizes the aquifer rocks that host the groundwater for long periods of time and over long subsurface flow-paths. REY concentrations and patterns reflect different types and rates of W/R reactions along the flow path of groundwater than those of the major solutes. Grouping stable isotopes of H₂O according to the REY signatures of the respective samples, improves the definition of the origin of groundwater (Möller et al., 2003, Möller et al., 2006, Möller et al., 2009a, Siebert et al., 2009). By including lithological and structural information on the available aquifers, it is possible to reconstruct the different flow paths of groundwater. Leakages or interaquifer flow may be detected by inconsistencies between the known lithologies of the recharge areas and the catchment-related interpretation of REY distribution patterns. Mixing with ascending brines is shown by the increased salinity of groundwater. REY patterns are less affected because the volumes of admixed brines are small and their REY patterns are often similar to those of the groundwaters.

The exact identification of different groundwater bodies, their natural replenishment areas and the definition of their flow regimes are necessary steps in establishing any reliable water balance and a smart water- and land-use management scheme which is even more important if transboundary groundwater basins are concerned.

Section snippets

Regional hydrogeological setting

The Bet She’an and Harod Valleys (32.37°–32.60°N and 35.42°–35.60°E) are the surface manifestation of a deep morphotectonic depression, which developed due to the Dead Sea rifting since the Miocene. The valleys diverge from the Lower Jordan Valley and separate the calcareous mountains of Gilboa and Faria (mountains of Judea and Samaria) to the south from the basaltic plateau of the eastern Lower Galilee to the north (locally known as the Issakhar plateau) (Fig. 1a and b). From these heights,

Behavior of REY in water–rock interaction in semi-arid regions

The study of REY patterns in river water from Norway showed some resemblance with the country rocks (Banks et al., 1999). While studying the characterization of recharge areas in the Central Jordan Valley by REY and stable isotopes of H₂O, it was shown that recharges from lithologically different replenishment areas could be identified by this methodology Möller et al. (2009a).

Under the semi-arid climate and poor vegetation cover of the study area, the influence of organic ligands on REY

Isotopes of H₂O

Apart from the effects of distance to the sea, elevation and temperature, the isotopic composition of recharge water is subjected to the origin of precipitation and hence to its initial composition. δD and δ¹⁸O are highly sensitive in respect to evaporation. The isotopic composition of intensely evaporated water bodies such as inland lakes, follow a distinct pattern up to highly enriched values, far beyond the standard V-SMOW (Gat, 1996, Siebert, 2006). Before infiltrating into subsurface

Sampling procedure

During a field campaign in November 2008, water samples were collected from 16 sources of groundwater in the Bet She’an and Harod areas. Samples were taken from distinct sources of the three main aquifers (Judea and Avedat Groups and basalts) as well as from springs, which were assumed to yield water from different sources. At each sampling site a total of about 4 L was collected in HD–PE bottles. REY samples were filtered using Sartobran 0.2 μm filter cartridges coupled to a peristaltic pump.

Major elements

Magnesium, Ca and Sr, were determined by ICP-MS, while K, Na, Ba and Li were determined by ICP-AES using matrix-adjusted standard solutions for calibration. Chloride, Br⁻ and ${SO}_{4}^{2 -}$ were determined by ion chromatography. The concentration of ${HCO}_{3}^{-}$ was Gran-titrated adjusting the waters to pH 4.3 with H₂SO₄. Data are presented in Table 2.

Rare earth elements and yttrium

Because of low concentrations, rare earths (REE) and Y were pre-concentrated by the following method. Approx. 3 L of filtered groundwater were adjusted to pH 2 by

Macrochemical indications

All groundwater from the Bet She’an region show lower Na/Cl molar ratios than those of halite dissolution and freshwater-diluted seawater (Fig. 3a). In the Br vs. Cl plot, the groundwater from limestone and basaltic catchments show different ratios (Fig. 3b). Irrespective of original aquifers, all waters are nearly saturated with respect to calcite; some are also saturated with dolomite. None is saturated with respect to anhydrite or gypsum (Table 4). In all waters the Ca/Mg molar ratios are

Water resources along the northern and eastern margins of Mt. Gilboa

Isotopic compositions of spring and well waters along the margins of Mt. Gilboa plot sub-parallel to the local MWL ranging from Revaya 1 (δ¹⁸O = −5.21‰ and δD = −25.65‰) to Mayan Harod (δ¹⁸O = −4.32‰ and δD = −20.28‰) (Fig. 4). The isotopically lightest waters appear in Revaya 1, Shoqeq 1, AMH 57, AMH 63 and AMH 66. Similar isotopic compositions were observed in groundwaters recharged in the Jerusalem/Ramallah district, which are assumed to be representative of the highest elevated regions along the

Conclusions

The present case study focused on the conjoint application of stable isotopes and REY distribution in groundwater aiming at the detailed elucidation of the replenishment areas of groundwater in wells, well-fields and springs located in areas highly disturbed by faults. In these areas intricate inter-aquifer flow is a common occurrence. This enables detecting the local areas of rainfall infiltration and, in connection with the position of wells or springs, the identification of groundwater flow

Acknowledgements

The authors greatly acknowledge the grant for this study from the German Federal Ministry of Education and Research (BMBF) within the multilateral IWRM-project SMART (02WM0801); (http://www.iwrm-smart.org; http://www.ufz.de/smart). The authors also thank K. Knöller, P. Blümel, D. Reichert, G. Stams, J. Steffen and H.J. Stärk (Helmholtz Centre for Environmental Research-UFZ) for the isotope and major ion analyses and P. Dulski and B. Zander (Helmholtz Centre Potsdam, GFZ) for REY analyses.

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Rare earth elements (REEs) have coherent properties and geochemical behaviours. Their distribution in groundwater has been investigated extensively owing to their characteristics and as a consequence of recently improved analytic accuracy (e.g. Willis and Johannesson, 2011; Yuan et al., 2014), can elucidate the water–rock interaction mechanisms (Dia et al., 2000; Leybourne et al., 2000; Hannigan and Sholkovitz, 2001; Worrall and Pearson, 2001; Biddau et al., 2002; Munemoto et al., 2015), the physico-chemical conditions of the aqueous system (Janssen and Verweij, 2003; Otsuda and Terakado, 2003; Gruau et al., 2004; Johannesson et al., 2004; Tang and Johannesson, 2003, 2006; Choi et al., 2009; Johannesson et al., 2005, 2011; Marsac et al., 2011; Stolpe et al., 2013; Davranche et al., 2015), and the dynamics of groundwater flow paths and mixing (Johannesson et al., 1997, 1999; Ojiambo et al., 2003; Tweed et al., 2006; Guo et al., 2010; Siebert et al., 2012). In groundwater REEs' concentrations and fractionation patterns (e.g. Noack et al., 2014, and references therein), are capable to add valuable constraints on the evolution experienced by the aquatic system during the flow in the aquifer rock(s).
The Mount Vulture basin, which mainly consists of pyroclastic and subordinate lava flow layers, is one of the most important aquifers for drinking water and irrigation supply in southern Italy. In this study, we investigated the geochemical behaviour of the rare earth elements (REEs) in the groundwater of this aquatic system, assessing fractionation patterns and performing speciation calculations to elucidate the geochemical processes affecting the REEs' distribution.
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The hydrochemical identification of groundwater flowing to the Bet She’an-Harod multiaquifer system (Lower Jordan Valley) by rare earth elements, yttrium, stable isotopes (H, O) and Tritium

Abstract

Highlights

Introduction

Section snippets

Regional hydrogeological setting

Behavior of REY in water–rock interaction in semi-arid regions

Isotopes of H2O

Sampling procedure

Major elements

Rare earth elements and yttrium

Macrochemical indications

Water resources along the northern and eastern margins of Mt. Gilboa

Conclusions

Acknowledgements

Appl. Geochem.

Geochim. Cosmochim. Acta

Appl. Geochem.

Chem. Geol.

Geochim. Cosmochim. Acta

Geochim. Cosmochim. Acta

Geochim. Cosmochim. Acta

Earth Planet. Sci. Lett.

Geochim. Cosmochim. Acta

Water Res.

Geochim. Cosmochim. Acta.

Chem. Geol.

Geochim. Cosmochim. Acta

Chem. Geol.

Chem. Geol.

Geochim.Cosmochim. Acta

Chem. Geol.

J. Geochem. Explor.

J. Hydrol.

J. Hydrol.

J. Hydrol.

Israel J. Hydrol.

Geochim. Cosmochim. Acta

Geochim. Cosmochim. Acta

Chem. Geol.

Chem. Geol.

Assessment of hydraulic parameters of the aquifers around the Sea of Galilee

Ground Water

Isotopes of H₂O