Geochemical modeling of groundwater in southern plain area of Pengyang County, Ningxia, China

AbstractThe purpose of this paper is to examine the evolution mechanisms of a hydrochemical field and to promote its benefits to the living standards of local people and to the local economy in the southern plain area of Pengyang County, in Ningxia, China. Based on understanding of the hydrogeological conditions in Pengyang County, the chemical evolution characteristics of groundwater in the plain area were analyzed. PHREEQC geochemical modeling software was used to perform hydrochemical modeling of water-rock interaction and to quantitatively analyze the evolution processes and the formation mechanisms of the local groundwater. Geochemical modeling was performed for two groundwater paths. The results showed that, along path 1, Na+ adsorption played the leading role in the precipitation process and its amount was the largest, up to 6.08 mmol/L; cation exchange was significant along path 1, while along simulated path 2, albite accounted for the largest amount of dissolution, reaching 9.06 mmol/L, and the cation exchange was not significant. According to the modeling results, along the groundwater flow path, calcite and dolomite showed oversaturated status with a precipitation trend, while the fluorite and gypsum throughout the simulated path were not saturated and showed a dissolution trend. The total dissolved solids (TDS) increased and water quality worsened along the flow path. The dissolution reactions of albite, CO2, and halite, the exchange adsorption reaction of Na+, and the precipitation of sodium montmorillonite and calcite were the primary hydrogeochemical reactions, resulting in changes of hydrochemical ingredients

Macroscopic, optical and diffraction assessment of encrustations and SEM analyses of phototrophic microbial mats from wellheads and select zones of emergence of mineral water in Serbia

Investigations focusing on wellhead encrustations within select zones of emergence of mineral water, in different hydrogeological provinces, were conducted from 2014 to 2017 in Serbia. They included: well BB-1 in Bogatić (Inner Dinaric Alps of western Serbia), wells LB-4 and LB-5 in Lukovska Banja (Šumadija-Kopaonik-Kosovo Province), and wells VG-2 and VG-3 in Vranjska Banja (Serbian Crystalline Core). The studied occurrences belong to the group of hot mineral waters, with temperatures ranging from 62°C to 93.9°C, and total dissolved solids (TDS) from 600 to 1267 mg/L. They are mildly acidic to mildly alkaline (pH 6.6 – 8.0) and their genetic types are HCO3--Na++K+ (Bogatić and Lukovska Banja) and SO42-, HCO3--Na++K+ (Vranjska Banja). Macroscopic, optical and diffraction assessment revealed that the encrustations comprised calcite and aragonite minerals, along with some local quartz, muscovite, albite and clinochlore. The conclusion was that there was a predominant presence of calcium carbonate in all the occurrences, represented by crystalline calcite grains, characteristically birefractive, and dark, semitranslucent grains in the form of microcrystalline calcite highly stained by iron hydroxides (Bogatić), as well as crystalline calcite with radially developed carbonate - aragonite (Lukovska Banja) and rod-like and filamentous aggregates of aragonite and calcite, highly translucent in places (Vranjska Banja).The texture of the samples exhibits alternating horizontal or wavy carbonate laminae. In Vranjska Banja, they include thin micritic to medium crystalline laminae and laminae composed of aggregates of aragonite needles in the form of bunch. In Bogatić and Lukovska Banja, there are thick micritic and highly porous laminae, 0.025 to 1 mm thick, or interlayers of a coarser crystalline structure. Apart from encrustations, all the occurrences exhibit phototrophic microbial mats, which were analyzed by scanning electron microscopy. The onset and progress of encrustation are primarily influenced by the physical and chemical composition of the mineral water (T, pH, TDS, HCO3-, Ca2+, CO2, etc.), as corroborated by hydrogeochemical modeling software PHREEQC 3.4.0. In addition, phototrophic biofilms might be contributing to the creation and accumulation of minerals in the encrustations.</p

Procesos hidrogeoquímicos en las aguas subterráneas de la cuenca de la laguna Mar Chiquita, provincia de Buenos Aires

Fil: Glok Galli, Melisa. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata; ArgentinaFil: Martínez, Daniel E.. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata; ArgentinaFil: Kruse, Eduardo Emilio. Cátedra de Hidrología General. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Lima, María Lourdes. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata; Argentin

Hydrogeochemical Modeling of Groundwater in the Gadilam River Basin, South India

Hydrogeochemistry of a region is a reflection of hydrodynamic process, composition of lithology and physical constraints. The water chemistry is the resultant of all biogeochemical processes and reactions, which have acted on water from the moment it has condensed in atmosphere till the time it's discharged. A case study has been carried out in a varied lithological terrain with Archaean, Alluvium and Tertiary rocks to unravel the hydrogeochemical process. The dominant facies in the entire litho units is sodium - chloride type indicating saline nature in the groundwater. The speciation of bicarbonate, sulphate and phosphate in the groundwater samples in different litho units was determined using the computer program WATQ4F. This study reveals that higher speciation with increasing concentration of bicarbonate in summer and south west monsoon indicates static environment, whereas lesser speciation in north east monsoon and post monsoon indicates flushing environment in the basin. Higher speciation with lesser contribution of sulphate in summer and south west monsoon and an increasing trend of speciation in north east monsoon and post monsoon was observed

The VISHMOD methodology with hydrochemical modeling in intermountain (karstic) aquifers: case of the Sierra Madre Oriental, Mexico

"Hydrogeochemistry can be studied qualitatively using graphics such as scatter plots and Piper, Durov, and Schoeller diagrams, among others, and quantitatively by applying mass balance mixing models. The VISHMOD methodology (Virtual Samples in Hydrochemical Modeling) combines these two forms of hydrogeochemical characterizations. It is performed by applying hydrogeochemical modeling to virtual samples. This method makes standardization and control possible in order to demonstrate the extent to which a model is able to reproduce field measurements. Therefore, hydrogeochemical models of hydrogeological systems must be calibrated. This methodology was applied to carbonate and homogeneous media in the Sierra Madre Oriental in Mexico. Using the VISHMOD methodology in this region resulted in the classification of the water type as calcium bicarbonate (Ca-HCO3), representing a ternary mixture in which 45.5% was associated with local flow, 38.5% to intermediate flow and 16.5% to water-rock interaction. The main mineral phases were saturated calcite and sub-saturated dolomite, both from limestone contained in the Tamaulipas Formation.

Effect of sludge amendment on remediation of metal contaminated soils

Peer ReviewedPostprint (published version

Application of groundwater aggressiveness assessment method for estimation of the karst process at main gas pipeline construction

Main pipelines maintenance is connected with hazard engineering and geological working conditions. The article deals with the use of groundwater aggressiveness assessment method to estimate the karst processes development during the construction of main gas pipelines. The possibility of using this method is analyzed on the example of the initial section of the designed gas pipeline "Power of Siberia" (section "Chayanda-Lensk"). The calculation of the nonequilibrium index Ca was made in accordance with the geotechnical survey data. The dependencies between the geomorphological features of the terrain and the natural waters aggressiveness were determined

Impacts of Shallow Geothermal Energy on Groundwater Quality: A Hydrochemical and geomicrobial study of the effects of ground source heat pumps and aquifer thermal energy storage

Stuijfzand, P.J. [Promotor]Breukelen, B.M. van [Copromotor