scholarly journals Origin of brackish groundwater in a sandstone aquifer on Bornholm, Denmark

2008 ◽  
Vol 39 (3) ◽  
pp. 209-222 ◽  
Author(s):  
N. O. Jørgensen ◽  
J. Heinemeier
Keyword(s):  
Water Body ◽  
Lower Cambrian ◽  
Crystalline Basement ◽  
Water Type ◽  
Rock Interaction ◽  
Isotopic Signatures ◽  
Sandstone Aquifer ◽  
Hydrochemical Data ◽  
Isotopic Studies ◽  
Water Rock Interaction

A multi-isotope approach in combination with hydrochemical data and borehole logging is applied to identify the source of brackish groundwater in a borehole in the well field of Neksø Municipal Waterworks in Bornholm, Denmark. The aquifer lithology consists of fractured Lower Cambrian sandstones resting on Proterozoic crystalline basement. The water body in the studied borehole is significantly stratified with respect to the hydrochemical and isotopic signatures and reveal a Na–Ca–Cl–HCO3 water type and TDS values >1,000 mg/L below a halocline at 40–55 m below measurement point (bmp). The occurrence of brackish groundwater is remarkable for this aquifer, which otherwise yields potable groundwater of good quality. The stable isotope (18O and 2H) compositions indicate a meteoric origin of the brackish groundwater, which rules out seawater intrusion into the aquifer. 14C activities show apparent 14C ages of the brackish groundwater in the range 2200–4300 yr (BP), whereas the freshwater samples above the halocline indicate modern age. Hydrochemical (Cl/Br and Sr) and isotopic studies (18O, 2H and 87Sr/86Sr) of the brackish groundwater point to a well-mixed and homogeneous water body reflecting long water–rock interaction and suggest a contribution of palaeowater from the fractured crystalline basement which has intruded into the Lower Cambrian sandstone aquifer.

Variation in kaolinite morphology with growth temperature in isotopically mixed pore-fluids, Brent Group, UK North Sea

Clay Minerals ◽  
1994 ◽  
Vol 29 (4) ◽  
pp. 591-608 ◽  
Author(s):  
M. Osborne ◽  
R. S. Haszeldine ◽  
A. E. Fallick
Keyword(s):  
Meteoric Water ◽  
Pore Space ◽  
Pore Waters ◽  
The West ◽  
Rock Interaction ◽  
Isotopic Studies ◽  
Reservoir Sandstones ◽  
Oxygen Isotopic ◽  
Low Degrees ◽  
Water Rock Interaction

AbstractDiagenetic kaolinite in reservoir sandstones of the Brent Group precipitated following the dissolution of detrial feldspar. Two distinct morphologies of kaolinite occur: (1) early diagenetic vermiform kaolinite which is often associated with expanded detrital micas; (2) later diagenetic ‘blocky’ kaolinite. Combined hydrogen and oxygen isotopic studies suggest that vermiform kaolinite precipitated at 25–50°C, and blocky kaolinite at 50–80°C, from pore-waters of a similar isotopic composition (δ18O = −6.5 to −3.5‰). These pore-waters are interpreted to be either a mixture of meteoric and compactional waters, or alternatively a meteoric water that had evolved isotopically due to water-rock interaction. Kaolinite precipitation occurred predominantly during the late Cretaceous to early Eocene. Influx of meteoric water into the Brent Group, probably occurred during the Palaeocene. Fluid flow across the entire basin was driven by a hydrostatic head on the East Shetland Platform palaeo-landmass to the west. The development of the two kaolinite morphologies is possibly related to the degree of supersaturation at the time of precipitation. At low degrees of supersaturation, vermiform kaolinite precipitated slowly upon detrital mica surfaces. Blocky kaolinite precipitated more rapidly into open pore-space at higher degrees of supersaturation. Precipitation of blocky kaolinite was perhaps triggered by the decay of oxalate.

scholarly journals Contamination risk assessment of the Transboundary Zeravshan River using chemical and isotopic studies

2019 ◽  
Vol 98 ◽  
pp. 07021
Author(s):  
Parviz Normatov ◽  
Inom Normatov
Keyword(s):  
River Water ◽  
Small Rivers ◽  
Rock Interaction ◽  
Low Salinity ◽  
Isotopic Studies ◽  
Rain Events ◽  
Isotope Analyses ◽  
Dissolution Of Minerals ◽  
Water Rock Interaction ◽  
Water Dissolution

The results of chemical and isotope analyses of water of the Zeravshan River are presented. Results show that the low salinity of the river water in the upstream reach is formed mainly by water dissolution of minerals in natural rocks, i.e. the existence of a water-rock interaction process. The detection of heavy cations in the composition of the river water is due to their transport long distances in the form of microparticles by wind and accumulation in snow cover and glaciers. During the melting of snow and glaciers, and during rain events, pollutants are carried by streams, small rivers, and finally by Zeravshan River that distributes the pollutants over long distances.

scholarly journals Hydrochemical Zoning and Chemical Evolution of the Deep Upper Jurassic Thermal Groundwater Reservoir Using Water Chemical and Environmental Isotope Data

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1162
Author(s):  
Florian Heine ◽  
Kai Zosseder ◽  
Florian Einsiedl
Keyword(s):  
Upper Jurassic ◽  
Cold Climate ◽  
Water Type ◽  
Molasse Basin ◽  
The South ◽  
Rock Interaction ◽  
Environmental Isotope ◽  
Water Types ◽  
Thermal Groundwater ◽  
Water Rock Interaction

A comprehensive hydrogeological understanding of the deep Upper Jurassic carbonate aquifer, which represents an important geothermal reservoir in the South German Molasse Basin (SGMB), is crucial for improved and sustainable groundwater resource management. Water chemical data and environmental isotope analyses of D, 18O and 87Sr/86Sr were obtained from groundwater of 24 deep Upper Jurassic geothermal wells and coupled with a few analyses of noble gases (3He/4He, 40Ar/36Ar) and noble gas infiltration temperatures. Hierarchical cluster analysis revealed three major water types and allowed a hydrochemical zoning of the SGMB, while exploratory factor analyses identified the hydrogeological processes affecting the water chemical composition of the thermal water. Water types 1 and 2 are of Na-[Ca]-HCO3-Cl type, lowly mineralised and have been recharged under meteoric cold climate conditions. Both water types show 87Sr/86Sr signatures, stable water isotopes values and calculated apparent mean residence times, which suggest minor water-rock interaction within a hydraulically active flow system of the Northeastern and Southeastern Central Molasse Basin. This thermal groundwater have been most likely subglacially recharged in the south of the SGMB in close proximity to the Bavarian Alps with a delineated northwards flow direction. Highly mineralised groundwater of water type 3 (Na-Cl-HCO3 and Na-Cl) occurs in the Eastern Central Molasse Basin. In contrast to water types 1 and 2, this water type shows substantial water-rock interaction with terrestrial sediments and increasing 40Ar/36Ar ratios, which may also imply a hydraulic exchange with fossil formation waters of overlying Tertiary sediments.

Geochemical modeling of chromium oxidation and treatment of polluted waters by RO/NF membrane processes

2020 ◽  
Author(s):  
Ilaria Fuoco ◽  
Alberto Figoli ◽  
Alessandra Criscuoli ◽  
Rosanna De Rosa ◽  
Bartolo Gabriele ◽  
...  
Keyword(s):  
Reaction Path ◽  
Geochemical Modeling ◽  
High Mobility ◽  
Water Type ◽  
Rock Interaction ◽  
Serpentine Minerals ◽  
Path Modelling ◽  
Reaction Path Modelling ◽  
Polluted Waters ◽  
Water Rock Interaction

<p>Geogenic Cr(VI) contamination is a worldwide environmental issue which mainly occurs in areas where ophiolitic rocks crop out. In these areas Cr (VI) can reach high concentrations into groundwaters becoming highly dangerous for human health. Indeed Cr(VI) is recognized as highly toxic element with high mobility and bioavailability [1]. Due to these features, starting from July 2017, Italian government has lowered the Cr(VI) limit value for drinking water to 10 µg/L. To improve the living standards in contaminated areas, it is needed (i) to understand the release and fate of contaminant during the water-rock interaction and (ii) to develop efficient remediation systems for natural polluted waters. In this regard, a complementary study on genesis and treatment of a Cr-rich groundwater coming from Italian ophiolitic aquifers was conducted. Reaction path modelling is a proven geochemical tool to understand the release of Cr and its oxidation from Cr(III) to Cr(VI) during the water-rock interaction. The generally accepted hypothesis of scientific community is that geogenic Cr(III) oxidation  is driven by the reduction of trivalent and tetravalent manganese (Mn(III); Mn (IV)) [2] whereas in this work the role of trivalent Fe hosted in serpentine minerals was re-evaluated. Unlike Mn, Fe is the main oxidant present in suitable amount in these rocks. Literature data confirmed the presence of Fe(III) into serpentine minerals hence reaction path modelling was performed varying the Fe (III)/Fe(tot) ratio ranging  from 0.60 to 1.00. The theoretical paths, reproduce the analytical concentrations of relevant solutes, including Cr(VI), in the Mg-HCO<sub>3</sub> water type hosted in the ophiolitic aquifers of Italy [3]. With increasing of Fe(III)/Fe(tot) ratio in serpentine minerals, high Cr(VI) concentration hold into solution until high alkalinity values. In addition, the spring with the highest Cr(VI) content (75 µg/L) was treated to lower its concentration below the threshold values.  In this work membrane technologies were used as  innovative method considering their many benefits, like the improvement of product quality without using chemicals [4]. A laboratory-scale set-up was used to carry out both Nanofiltration (NF) and Reverse Osmosis (RO) experiments. The experiments were conducted on different commercial membranes: one NF membrane module named DK (polyamide) and two RO membrane modules named AD (polyamide) and CD (cellulose).Tests were performed varying the operating pressures, and high Cr(VI) rejections (around 95%) were reached for all tested membranes, leading to a water containing Cr(VI) in concentrations below the threshold limits. The high flux, obtained already at lower operating pressures (27 L/m<sup>2</sup>h-10bar), combined with high selectivity towards Cr(VI) makes NF a favorable remediation option. The results obtained in this work are in line with the few data available in the literature for natural contaminated waters and there are quite promising for future scientific developments and application.</p><p> </p><p> </p><p>References</p><p>[1]Marinho B. A. et al., 2019. Environ Sci Pollut Res, 26(3), 2203-2227</p><p>[2]Oze C. et al., 2007. Proc. Natl. Acad. Sci. 104, 6544–6549</p><p>[3]Apollaro C. et al., 2019. Sci. Total Environ. 660, 1459-1471</p><p>[4]Figoli  A. & Criscuoli  A., 2017. Springer (Singapore); ISBN:9789811056215</p>

scholarly journals Comparison Of Isotope And Hydrochemical Characteristics Of Springs In Sembalun – Rinjani Area, East Lombok, West Nusa Tenggara, Indonesia Before And After The Earthquake Events In 2018

2021 ◽  
Vol 71 ◽  
pp. 215-226
Author(s):  
Satrio Satrio ◽  
◽  
Rasi Prasetio ◽  
B. Yoseph C.S.S. Syah Alam ◽  
M. Sapari D. Hadian ◽  
...  
Keyword(s):  
Meteoric Water ◽  
Hot Spring ◽  
Hydrochemical Characteristics ◽  
Rock Interaction ◽  
Piper Diagram ◽  
Hydrochemical Data ◽  
Hydrochemical Study ◽  
Before And After ◽  
Hydrochemical Composition ◽  
Water Rock Interaction

The current 2019 isotope and hydrochemical study of hot and cold springs in Sembalun - Rinjani area is a re-assessment of previous similar study in 2012. The aim of this study is to assess the isotope and hydrochemical characteristics of springs due to the earthquake events in 2018. After the earthquake events in 2018, the stable isotopes δ18O and δ2H composition of Sebau hot spring and most of cold springs is shifted into more depleted values which may indicate water-rock interaction or interaction with cold waters which has more depleted δ18O and δ2H values. Also, Sebau hot spring is still plotted at mixing line of meteoric and andesitic water, but still dominant meteoric water. The hydrochemical data of all cold springs and Orok river show the enrichment of Na, probably from silicates weathering or the cation exhchange. While hydrochemical composition of Sebau hot spring is significantly decreased, except SO4, probably due to dilution with cold waters before the thermal water reach the surface. The Piper diagram showed that cold springs and Orok river are Ca-Mg-HCO3 type before and after the earthquake events. While Sebau hot spring is shifted from Ca-Cl type into mixed Ca-Mg-Cl type after the earthquake events. The temperature of Sebau hot spring slightly decreased from 35.5 °C to 34.8 °C after the earthquake events, while Na/K geothermometer calculation also indicate decreasing of sub-surface temperature, i.e. from 146–165 °C to 130–150 °C.

Wipp Site Studies: Secondary Selenite Veins in the Rustler Formation and Dewey Lake Red Beds

1987 ◽  
Vol 112 ◽  
Author(s):  
D. G. Brookins ◽  
S. J. Lambert
Keyword(s):  
Surface Water ◽  
Trace Element Data ◽  
Isotopic Data ◽  
Red Beds ◽  
Rock Interaction ◽  
Near Surface ◽  
Secondary Sources ◽  
Isotopic Compositions ◽  
Isotopic Studies ◽  
Water Rock Interaction

AbstractDefense-generated transuranic (TRU) waste will be stored at WIPP in the bedded halite of the Salado Formation (Permian), which is overlain by the impure Permian evaporites of the Rustler Formation and the Dewey Lake Red Beds. Both the Rustler and Dewey Lake contain abundant to less common secondary selenite veins of uncertain origin, and dissolution zones occur in the Rustler. The Rustler Formation also contains two dolomite aquifers, the Magenta and Culebra members. The purpose of this study is to determine whether vein selenite is locally derived, or has been introduced in moving groundwater solutions. We have used Sr isotopic studies and REE, U and other trace element data to address the problem. The Sr isotopic data show that neither the Salado nor Rustler anhydrites have exchanged with secondary sources of Sr, and this is supported by the REE and U data. Further, selenite veins from the Rustler possess Sr isotopic compositions identical to the Rustler, indicating local origin, and this is also supported by the U and REE data. Selenite veins from the Dewey Lake Red Beds possess Sr isotopic compositions closer to surface caliche deposits, and may contain near-surface derived Sr. U and REE data show more scatter and evidence for extrinsic sources than the vein/host-rock pairs from the Rustler. Sr isotopic compositions of the Magenta and Culebra indicate that the Magenta has undergone less water/rock interaction than the Culebra. Collectively, the data argue for more possible surface or near-surface water/rock interactions in the Dewey Lake Red Beds than in the Rustler Formation; such interactions in the Salado Formation have been minimal.

87SR/86SR, δ18O AND NOBLE GASES AS TRACERS OF WATER-ROCK INTERACTION IN THE THEISTAREYKIR GEOTHERMAL FIELD

2020 ◽  
Author(s):  
Marie Haut-Labourdette ◽  
◽  
Daniele Pinti ◽  
André Poirier ◽  
Marion Saby ◽  
...  
Keyword(s):  
Noble Gases ◽  
Geothermal Field ◽  
Rock Interaction ◽  
Water Rock Interaction

scholarly journals Geochemical and isotopic evidence of groundwater salinization processes in the Essaouira region, north-west coast, Morocco

2021 ◽  
Vol 3 (7) ◽  
Author(s):  
Otman EL Mountassir ◽  
Mohammed Bahir ◽  
Driss Ouazar ◽  
Abdelghani Chehbouni ◽  
Paula M. Carreira
Keyword(s):  
Groundwater Recharge ◽  
West Coast ◽  
Exchange Process ◽  
Environmental Isotopes ◽  
Annual Rainfall ◽  
Groundwater Salinization ◽  
Rock Interaction ◽  
North West ◽  
The North ◽  
Water Rock Interaction

AbstractThe city of Essaouira is located along the north-west coast of Morocco, where groundwater is the main source of drinking, domestic and agricultural water. In recent decades, the salinity of groundwater has increased, which is why geochemical techniques and environmental isotopes have been used to determine the main sources of groundwater recharge and salinization. The hydrochemical study shows that for the years 1995, 2007, 2016 and 2019, the chemical composition of groundwater in the study area consists of HCO3–Ca–Mg, Cl–Ca–Mg, SO4–Ca and Cl–Na chemical facies. The results show that from 1995 to 2019, electrical conductivity increased and that could be explained by a decrease in annual rainfall in relation to climate change and water–rock interaction processes. Geochemical and environmental isotope data show that the main geochemical mechanisms controlling the hydrochemical evolution of groundwater in the Cenomanian–Turonian aquifer are the water–rock interaction and the cation exchange process. The diagram of δ2H = 8 * δ18O + 10 shows that the isotopic contents are close or above to the Global Meteoric Water Line, which suggests that the aquifer is recharged by precipitation of Atlantic origin. In conclusion, groundwater withdrawal should be well controlled to prevent groundwater salinization and further intrusion of seawater due to the lack of annual groundwater recharge in the Essaouira region.

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