Hydrogeochemical interpretation of South Korean groundwater monitoring data using Self-Organizing Maps

Choi, Byoung Young; Yun, Seong Taek; Kim, Kyoung-Ho; Kim, Ji Wook; Kim, Hyang Mi; Koh, Yong–Kwon

doi:10.1016/j.gexplo.2013.12.001

Cited by 90 publications

(22 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…PC4 has a high positive loading in Na + and high negative loadings in other three cations: Ca 2+ , K + and Mg 2+ . Therefore, it may represent the cation exchange process of clay particles, which is common in arid and semi-arid environments [53,54,57]. …”

Section: Pca Resultsmentioning

confidence: 99%

“…NO 3 − in groundwater is not significantly influenced by rock-water interactions. Instead, it reflects the influences of anthropogenic activities, such as fertilization in irrigated farmlands, where excessive nitrate may leach into groundwater [14,54]. Among the 73 samples, 8 samples have NO 3 − concentrations greater than 44.3 mg/L, which exceed the drinking water standards defined by the WHO.…”

Section: Descriptive Statisticsmentioning

confidence: 99%

See 1 more Smart Citation

Investigating Hydrochemical Groundwater Processes in an Inland Agricultural Area with Limited Data: A Clustering Approach

Zheng

Zhang

et al. 2017

Water

View full text Add to dashboard Cite

Abstract:Groundwater chemistry data are normally scarce in remote inland areas. Effective statistical approaches are highly desired to extract important information about hydrochemical processes from the limited data. This study applied a clustering approach based on the Gaussian Mixture Model (GMM) to a hydrochemical dataset of groundwater collected in the middle Heihe River Basin (HRB) of northwestern China. Independent hydrological data were introduced to examine whether the clustering results led to an appropriate interpretation on the hydrochemical processes. The main findings include the following. First, in the middle HRB, although groundwater chemistry reflects primarily a natural salinization process, there are evidence for significant anthropogenic influence such as irrigation and fertilization. Second, the regional hydrological cycle, particularly surface water-groundwater interaction, has a profound and spatially variable impact on groundwater chemistry. Third, the interaction between the regional agricultural development and the groundwater quality is complicated. Overall, this study demonstrates that the GMM clustering can effectively analyze hydrochemical datasets and that these clustering results can provide insights into hydrochemical processes, even with a limited number of observations. The clustering approach introduced in this study represents a cost-effective way to investigate groundwater chemistry in remote inland areas where groundwater monitoring is difficult and costly.

show abstract

Section: Pca Resultsmentioning

confidence: 99%

Section: Descriptive Statisticsmentioning

confidence: 99%

Investigating Hydrochemical Groundwater Processes in an Inland Agricultural Area with Limited Data: A Clustering Approach

Zheng

Zhang

et al. 2017

Water

View full text Add to dashboard Cite

show abstract

“…In recent years, the assessment of both the geochemical state of groundwater and the impact of anthropogenic pollutants have become more important [4,16]. Most hydrogeochemical studies take the understanding of geology as a starting point, and later, analyze the quality of groundwater in order to define flow patterns and hydrogeological units [17].…”

Section: Figure 1 Location Of Study Areamentioning

confidence: 99%

Hydrogeochemical characterization and identification of a system of regional flow. Case study: the aquifer on the Gulf of Urabá, Colombia

Ossa

Betancur-Vargas

2018

Rev. Fac. Ing. Univ. Antioquia

View full text Add to dashboard Cite

ABSTRACT:Hydrogeochemistry is an essential tool for the verification of conceptual models, especially of groundwater flow models. This is even more relevant when dealing with complex hydrogeological models that have intercalating layers with different degrees of permeability, and regional flows contributing to the system. The hydrogeochemical characteristics of the Urabá-Colombia Aquifer and geological cross-sections were studied to establish possible processes that explain the groundwater flow evolution and the recharge zones. 4 flow lines were considered to show the groundwater evolution from Ca 2+ -HCO 3 -facies and a TDS concentration of approximately 400 mg/L, trough Ca 2+ -Mg 2+ -HCO 3 -and Na + -Mg 2+ -HCO 3 -facies, ending with Na + -HCO 3 -facies close to discharge area, with TDS=1,550 mg/L. Data on stable isotopes confirmed the groundwater flow directions. It is also clear that evolution orders correspond to the possible flow rates in areas with a homogeneous gradient, but with higher hydraulic conductivity conditions to the south and center, compared to the north. RESUMEN:La hidrogeoquímica constituye una herramienta fundamental para la verificación de los modelos conceptuales, en particular los modelos de flujo de aguas subterráneas, esto se hace aún más relevante cuando se tienen modelos hidrogeológicos complejos en los que se intercalan capas de distinta permeabilidad e intervienen flujos regionales. Analizando las características del Acuífero del Golfo de Urabá y secciones geológicas, fue posible establecer procesos que explican la evolución del flujo del agua subterránea y las zonas de recarga del acuífero. Se utilizaron 4 líneas de flujo para mostrar la evolución del agua subterránea de facies Ca 2+ -HCO 3 -y una concentración de STD de 400 mg/L aproximadamente, pasando por facies Ca 2+ -Mg 2+ -HCO 3 -y Na + -Mg 2+ -HCO 3 -, y finalizando con una facies Na + -HCO 3 -, cerca de la zona de descarga, con STD=1,550 mg/L aproximadamente. Algunos datos de isotopos estables sustentan la verificación de los sentidos de flujo hidrogeológico. También es claro que los ordines de evolución se corresponden con las posibles velocidades de flujo en zona con gradiente homogéneo pero condiciones de conductividad hidráulica más altas en el sur y centro que en el norte.

show abstract

“…In particular, fluoride is relatively enriched (up to 1.1 mg/L) in the lower aquifer groundwater. In South Korean groundwater, such enrichment of fluoride was interpreted as the result of dissolution of F-bearing silicate minerals during water-rock interaction [56,[58][59][60]. The enrichments of Na and Cl (and increasing TDS) in some samples from the lower gravel aquifer are possibly due to remnant seawater that was entrapped in the intermediate silty clay layer during the sea level rise, and that has been subsequently washed out during the deposition of recent point-bar sediment [26,61].…”

Section: Vertical Change Of Hydrochemistrymentioning

confidence: 99%

Lithologic Control of the Hydrochemistry of a Point-Bar Alluvial Aquifer at the Low Reach of the Nakdong River, South Korea: Implications for the Evaluation of Riverbank Filtration Potential

Moniruzzaman

Lee

Jung

et al. 2018

Water

Self Cite

View full text Add to dashboard Cite

To assess the groundwater−river water interaction in a point-bar alluvial aquifer as a crucial step in site assessment for riverbank filtration, hydrochemical and hydrogeologic investigations were performed on a riverine island at the low reach of the Nakdong River, South Korea. The site was evaluated for the application of large-scale bank filtration. Unconsolidated sediments (~40 m thick) of the island comprise fine- to medium-grained sand (upper aquifer), silty sand with clay intercalations, and sandy gravel (lower aquifer) in descending order. The intermediate layer represents an impermeable aquitard and extends below the river bottom. A total of 66 water samples were collected for this study; groundwater (n = 57) was sampled from both preexisting irrigation wells, and three multi-level monitoring wells (each 35 m deep). Groundwater chemistry is highly variable, but it shows a distinct hydrochemical change with depth: shallow groundwater (<25 m deep) from the upper aquifer is characteristically enriched in NO3− and SO42−, due to agricultural contamination from the land surface, while deeper groundwater (>25 m deep) from the lower aquifer is generally free of NO3− and relatively rich in F. The lower aquifer groundwater is also higher in pH, and concentrations of K+, Mg2+, and HCO3−, indicating that the aquifer is likely fed by regional groundwater flow. Such separation of groundwater into two water bodies is the result of the existence of an impermeable layer at intermediate depth. In addition, the hyporheic flow of river water is locally recognized at the upstream part of the upper aquifer as the zone of low TDS (Total Dissolved Solids) values (<200 mg/L). This study shows that the study site does not seem to be promising for large-scale riverbank filtration because 1) the productive, lower aquifer is not directly connected to the bottom of the river channel, and 2) the upper aquifer is severely influenced by agricultural contamination. This study implies that the subsurface hydrogeologic environment should be carefully investigated for site assessment for riverbank filtration, which can be aided by a detailed survey of groundwater chemistry.

show abstract

Hydrogeochemical interpretation of South Korean groundwater monitoring data using Self-Organizing Maps

Cited by 90 publications

References 57 publications

Investigating Hydrochemical Groundwater Processes in an Inland Agricultural Area with Limited Data: A Clustering Approach

Investigating Hydrochemical Groundwater Processes in an Inland Agricultural Area with Limited Data: A Clustering Approach

Hydrogeochemical characterization and identification of a system of regional flow. Case study: the aquifer on the Gulf of Urabá, Colombia

Lithologic Control of the Hydrochemistry of a Point-Bar Alluvial Aquifer at the Low Reach of the Nakdong River, South Korea: Implications for the Evaluation of Riverbank Filtration Potential

Contact Info

Product

Resources

About