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| Author | Siarkos, I.; Latinopoulos, P. | ||||
| Title | Modeling seawater intrusion in overexploited aquifers in the absence of sufficient data: application to the aquifer of Nea Moudania, northern Greece | Type | Journal Article | ||
| Year | 2016 | Publication  |
Hydrogeology Journal | Abbreviated Journal | Hydrogeology J. |
| Volume | 24 | Issue | Pages | 2123–2141 | |
| Keywords | Groundwater flow, Seawater intrusion, Numerical modeling, Greece, Sensitivity analysis | ||||
| Abstract | In many coastal areas, overexploitation of groundwater resources has led both to the quantitative degradation of local aquifers and the deterioration of groundwater quality due to seawater intrusion. To investigate the behavior of coastal aquifers under these conditions, numerical modeling is usually implemented; however, the proper implementation of numerical models requires a large amount of data, which are often not available due to the time-consuming and costly process of obtaining them. In the present study, the investigation of the behavior of coastal aquifers under the lack of adequate data is attempted by developing a methodological framework consisting of a series of numerical simulations: a steady-state, a false-transient and a transient simulation. The sequence and the connection between these simulations constitute the backbone of the whole procedure aimed at adjusting the various model parameters, as well as obtaining the initial conditions for the transient simulation. The validity of the proposed methodology is tested through evaluation of the model calibration procedure and the estimation of the simulation errors (mean error, mean absolute error, root mean square error, mean relative error) using the case of Nea Moudania basin, northern Greece. Furthermore, a sensitivity analysis is performed in order to minimize the error estimates and thus to maximize the reliability of the models. The results of the whole procedure affirm the proper implementation of the developed methodology under specific conditions and assumptions due to the lack of sufficient data, while they give a clear picture of the aquifer’s quantitative and qualitative status. |
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| Address | Ilias Siarkos: isiarkos@civil.auth.gr; Pericles Latinopoulos latin@civil.auth.gr | ||||
| Corporate Author | School of Civil Engineering, Aristotle University of Thessaloniki, GR54124 Thessaloniki, Greece | Thesis | |||
| Publisher | IAH | Place of Publication | Editor | Springer | |
| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1431-2174 | ISBN | Medium | ||
| Area | Hydrogeology; groundwater modelling, sea water intrusion | Expedition | Conference | ||
| Notes | Approved | yes | |||
| Call Number | MGRE @ redha.menani @ | Serial | 52 | ||
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| Author | Liu, Y.; Jin, M.; Wang, J. | ||||
| Title | Insights into groundwater salinization from hydrogeochemical and isotopic evidence in an arid inland basin | Type | Journal Article | ||
| Year | 2018 | Publication |
Hydrological Processes | Abbreviated Journal | |
| Volume | 32 | Issue | 20 | Pages | 3108-3127 |
| Keywords | deuterium excess, groundwater salinization, Northwest China, Manas River basin, stable isotopes | ||||
| Abstract | Abstract In the Manas River basin (MRB), groundwater salinization has become a major concern, impeding groundwater use considerably. Isotopic and hydrogeochemical characteristics of 73 groundwater and 11 surface water samples from the basin were analysed to determine the salinization process and potential sources of salinity. Groundwater salinity ranged from 0.2 to 11.91 g/L, and high salinities were generally located in the discharge area, arable land irrigated by groundwater, and depression cone area. The quantitative contributions of the evaporation effect were calculated, and the various groundwater contributions of transpiration, mineral dissolution, and agricultural irrigation were identified using hydrogeochemical diagrams and δD and δ18O compositions of the groundwater and surface water samples. The average evaporation contribution ratios to salinity were 5.87% and 32.7% in groundwater and surface water, respectively. From the piedmont plain to the desert plain, the average groundwater loss by evaporation increased from 7% to 29%. However, the increases in salinity by evaporation were small according to the deuterium excess signals. Mineral dissolution, transpiration, and agricultural irrigation activities were the major causes of groundwater salinization. Isotopic information revealed that river leakage quickly infiltrated into aquifers in the piedmont area with weak evaporation effects. The recharge water interacted with the sediments and dissolved minerals and subsequently increased the salinity along the flow path. In the irrigation land, shallow groundwater salinity and Cl− concentrations increased but not δ18O, suggesting that both the leaching of soil salts due to irrigation and transpiration effect dominated in controlling the hydrogeochemistry. Depleted δ18O and high Cl− concentrations in the middle and deep groundwater revealed the combined effects of mixing with paleo-water and mineral dissolution with a long residence time. These results could contribute to the management of groundwater sources and future utilization programs in the MRB and similar areas. | ||||
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| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ doi:10.1002/hyp.13243 | Serial | 178 | ||
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| Author | Kim, Y.; Lee, K.-S.; Koh, D.-C.; Lee, D.-H.; Lee, S.-G.; Park, W.-B.; Koh, G.-W.; Woo, N.-C. | ||||
| Title | Hydrogeochemical and isotopic evidence of groundwater salinization in a coastal aquifer: a case study in Jeju volcanic island, Korea | Type | Journal Article | ||
| Year | 2003 | Publication |
Journal of Hydrology | Abbreviated Journal | |
| Volume | 270 | Issue | 3 | Pages | 282-294 |
| Keywords | Jeju volcanic island, Coastal aquifer, Groundwater salinization, Hydrogeochemistry, Environmental isotopes, Mixing process | ||||
| Abstract | In order to identify the origin of saline groundwater in the eastern part of Jeju volcanic island, Korea, a hydrogeochemical and isotopic study has been carried out for 18 observation wells located in east and southeast coastal regions. The total dissolved solid contents of groundwaters are highly variable (77–21,782mg/l). Oxygen, hydrogen, sulfur, and strontium isotopic data clearly show that the saline water results from mixing of groundwater with seawater. Strontium isotopic compositions and Br/Cl and I/Cl ratios strongly suggest that the source of salinity is modern seawater intrusion. Hydrogeochemical characteristics based on bivariate diagrams of major and minor ions show that changes in the chemical composition of groundwater are mainly controlled by the salinization process followed by cation-exchange reactions. The highly permeable aquifers at the east coastal region are characterized by low hydraulic gradient and discharge rate and high hydraulic conductivity as compared with other regions. These properties enhance the salinization of groundwater observed in the study area. Based on the Cl, Br, and δ18O data, seawater was determined to have intruded inland some 2.5km from the coastline. Considering the poor correlation of sampling depth and Cl concentrations observed, the position of seawater-freshwater interface is not uniformly distributed in the study area, due to heterogeneities of the basaltic aquifers. | ||||
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| ISSN | 0022-1694 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ Kim2003282 | Serial | 172 | ||
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| Author | Han, D.M.; Song, X.F.; Currell, M.J.; Yang, J.L.; Xiao, G.Q. | ||||
| Title | Chemical and isotopic constraints on evolution of groundwater salinization in the coastal plain aquifer of Laizhou Bay, China | Type | Journal Article | ||
| Year | 2014 | Publication |
Journal of Hydrology | Abbreviated Journal | |
| Volume | 508 | Issue | Pages | 12-27 | |
| Keywords | Laizhou Bay, Coastal aquifers, Groundwater hydrochemistry, Stable isotopes, Saltwater intrusion | ||||
| Abstract | Summary A hydrochemical-isotopic investigation of the Laizhou Bay Quaternary aquifer in north China provides new insights into the hydrodynamic and geochemical relationships between freshwater, seawater and brine at different depths in coastal sediments. Saltwater intrusion mainly occurs due to two cones of depression caused by concentrated exploitation of fresh groundwater in the south, and brine water for salt production in the north. Groundwater is characterized by hydrochemical zonation of water types (ranging from Ca–HCO3 to Na–Cl) from south to north, controlled by migration and mixing of saline water bodies with the regional groundwater. The strong adherence of the majority of ion/Cl ratios to mixing lines between freshwater and saline water end-members (brine or seawater) indicates the importance of mixing under natural and/or anthropogenic influences. Examination of the groundwater stable isotope δ18O and δ2H values (between −9.5‰ and −3.0‰ and −75‰ and −40‰, respectively) and chloride contents (∼2 to 1000meq/L) of the groundwater indicate that the saline end-member is brine rather than seawater, and most groundwater samples plot on mixing trajectories between fresh groundwater (δ18O of between −6.0‰ and −9.0‰; Cl<5meq/L) and sampled brines (δ18O of approximately −3.0‰ and Cl>1000meq/L). Locally elevated Na/Cl ratios likely result from ion exchange in areas of long-term freshening. The brines, with radiocarbon activities of ∼30 to 60 pMC likely formed during the Holocene as a result of the sequence of transgression-regression and evaporation; while deep, fresh groundwater with depleted stable isotopic values (δ18O=−9.7‰ and δ2H=−71‰) and low radiocarbon activity (<20 pMC) was probably recharged during a cooler period in the late Pleistocene, as is common throughout northern China. An increase in the salinity and tritium concentration in some shallow groundwater sampled in the 1990s and re-sampled here indicates that intensive brine extraction has locally resulted in rapid mixing of young, fresh groundwater and saline brine. The δ18O and δ2H values of brines (∼−3.0‰ and −35‰) are much lower than that of modern seawater, which could be explained by 1) mixing of original (δ18O enriched) brine that was more saline than presently observed, with fresh groundwater recharged by precipitation and/or 2) dilution of the palaeo-seawater with continental runoff prior to and/or during brine formation. The first mechanism is supported by relatively high Br/Cl molar ratios (1.7×10−3–2.5×10−3) in brine water compared with ∼1.5×10−3 in seawater, which could indicate that the brines originally reached halite saturation and were subsequently diluted with fresher groundwater over the long-term. Decreasing 14C activities with increasing sampling depth and increasing proximity to the coastline indicate that the south coastal aquifer in Laizhou Bay is dominated by regional lateral flow, on millennial timescales. | ||||
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| ISSN | 0022-1694 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ Han201412 | Serial | 174 | ||
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| Author | Cary, L.; Petelet-Giraud, E.; Bertrand, G.; Kloppmann, W.; Aquilina, L.; Martins, V.; Hirata, R.; Montenegro, S.M.G.L.; Pauwels, H.; Chatton, E.; Franzen, Melissa; Aurouet, A.; Lasseur, E.; Picot-Colbeaux, G.; Guerrot, C.; Fléhoc, C.; Labasque, T.; Santos, Jeane Glaucia; Paiva, Anderson L.R.; Braibant, G.; Pierre, D. | ||||
| Title | Origins and processes of groundwater salinization in the urban coastal aquifers of Recife (Pernambuco, Brazil): a multi-isotope approach | Type | Journal Article | ||
| Year | 2015 | Publication |
Science of the Total Environment | Abbreviated Journal | |
| Volume | 530-531 | Issue | Pages | 411-429 | |
| Keywords | Salinization origins; Salinization processes; Groundwater; Coastal aquifer; Strontium isotopes; Boron isotopes; Recife; Brazil | ||||
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| Publisher | Elsevier | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ cary:hal-01161949 | Serial | 85 | ||
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