Cl− as a Chemical Fingerprint of Solute Transport in the Aquitard-Aquifer System of the North Jiangsu Coastal Plain, China

Detailed vertical profiles of Cl− in porewaters through the aquitard-aquifer system were used to yield solute transport mechanism and build a conceptual model regarding evolution processes and transport time of natural tracer migration in North Jiangsu coastal plain, China. One-dimensional vertical simulated models of Cl− profiles illustrate that diffusion appeared to be the dominant solute transport mechanism in the aquitard-aquifer system. A downward groundwater flow did not improve the fitness between simulated and measured values. Several simulated models were constructed and suggested that the evolution of the Cl− profiles is mainly ascribed to the introduction of seawater and freshwater of transgression-regression to the first confined aquifer and the upper boundary. Groundwater in the first confined aquifer recharged by the Late Pleistocene glacial meltwater (25–15 ka BP) was supported in response to the low Cl− concentrations. The shallow groundwater in the first confined aquifer and porewater with high salt were attributable to the Holocene seawater intrusion. These timeframes were also consistent favorably with the results of previous studies into the palaeohydrology of the study area.

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Ground-Water Flow Simulation for Management of a Regulated Aquifer System: A Case Study in the North Carolina Coastal Plain

Ground Water ◽

10.1111/j.1745-6584.1995.tb00020.x ◽

1995 ◽

Vol 33 (5) ◽

pp. 741-748 ◽

Cited By ~ 7

Author(s):

Jeffrey W. Reynolds ◽

Richard K. Spruill

Keyword(s):

North Carolina ◽

Ground Water ◽

Water Flow ◽

Coastal Plain ◽

Flow Simulation ◽

Ground Water Flow ◽

Aquifer System ◽

The North ◽

System A

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Hydrogeologic framework of the North Carolina Coastal Plain aquifer system

Open-File Report ◽

10.3133/ofr87690 ◽

1989 ◽

Cited By ~ 2

Author(s):

M.D. Winner ◽

R.W. Coble

Keyword(s):

North Carolina ◽

Coastal Plain ◽

Aquifer System ◽

The North ◽

Hydrogeologic Framework

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Salinity and modelling of the Annaba aquifer system, North-East of Algeria

Journal of Water and Land Development ◽

10.2478/jwld-2018-0030 ◽

2018 ◽

Vol 37 (1) ◽

pp. 113-120

Author(s):

Habiba Majour ◽

Azzedine Hani ◽

Larbi Djabri

Keyword(s):

Steady State ◽

Solute Transport ◽

History Matching ◽

Transport Model ◽

Water Levels ◽

Model Verification ◽

Confined Aquifer ◽

Deep Aquifer ◽

Aquifer System ◽

North East

Abstract The potentiometer area in the Annaba basin, covering an area of 264 km2, has declined considerably since 1995. The analysis of the chronological hydrographs (1991–2009) of the piezometric observations shows that this decline is related to about twenty years (20 years) drought that began in 1991. To synthesize hydrological data and study regional changes in aquifer interactions caused by changes in discharge, and determine the contamination of aquifers by salty intrusion in coastal areas, and making forecasts by the year 2023, a multi-layered transient model as well as a solute transport model has been developed. The groundwater flow was modelled using the finite difference method with a horizontal dimension of 500 × 500 m for the cells. The model consists of two layers, the first corresponding to the alluvial phreatic aquifer and the second to the deep confined aquifer, and is calibrated against the steady state groundwater heads recorded before 1996. Model verification was done by history matching over the period 1991–2009. Under steady-state conditions, the correspondence between simulated and observed water levels is generally good (average difference of 0.4 m). For the deep aquifer, the simulated time-series hydrographs closely match the recorded hydrographs for most of the observation wells. For the alluvial aquifer, the recorded hydrographs cover only a short time period, but they are reproduced. The model indicates that groundwater pumping induced a decrease in natural discharge, a downward leakage in most of the basin and a continual water-level decline. The model has also been applied to the analysis of recharge impact. Simulating the behaviour of the system over the period 1991–2009 without pumping indicated small changes in hydraulic head. These results show that the groundwater reservoir has a low recharge, but excellent hydraulic properties. A solute-transport model was used to study aquifer contamination from salty intrusion in coastal sectors; it was extended to the year 2023 by simulating an optimistic hypothesis that maintains present pumping until 2023. The model indicates that the head decrease of the alluvial phreatic and deep confined aquifers will be 4 m and 5 m respectively. The solute concentration in the deep confined aquifer will increase from 1 gꞏdm−3 (prior 2009) to 5 gꞏdm−3 in 2023.

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Quantifying and modelling the contribution of streams that recharge the Querença-Silves aquifer in the south of Portugal

Natural Hazards and Earth System Science ◽

10.5194/nhess-12-3217-2012 ◽

2012 ◽

Vol 12 (11) ◽

pp. 3217-3227 ◽

Cited By ~ 8

Author(s):

N. Salvador ◽

J. P. Monteiro ◽

R. Hugman ◽

T. Y. Stigter ◽

E. Reis

Keyword(s):

Water Availability ◽

Surface Runoff ◽

Flow Model ◽

Public Water Supply ◽

Groundwater Flow Model ◽

The South ◽

Aquifer System ◽

The North ◽

System A ◽

Water Courses

Abstract. The water balance of the mesocenozoic aquifers of the Algarve, in the south of Portugal has traditionally been estimated considering only direct ("autogenic") recharge from rainfall occurring in the area of the aquifers. Little importance has been attributed to so-called allogenic recharge, originating from streambed infiltration from runoff generated outside the aquifers, particularly in the Palaeozoic rocks to the north where runoff is high. The Querença-Silves (QS) aquifer is the most important aquifer of the region both for irrigation and public water supply. Several important and sensitive surface/groundwater ecotones and associated groundwater dependent ecosystems exist at the springs of the natural discharge areas of the aquifer system. A numerical flow model has been in constant development over the last few years and currently is able to reproduce the aquifer's responses to estimated direct recharge and abstraction for the years 2001–2010. However, recharge calculations for the model do not take into account allogenic recharge infiltration along influent reaches of streams. The quantification of allogenic recharge may further improve the assessment of water availability and exploitation risks. In this paper an attempt is made to quantify the average annual contribution of allogenic recharge to the QS aquifer, based on monitoring data of the principal water courses that cross the aquifer system. Significant uncertainties related to surface runoff generated within the aquifer area, as well as areal recharge were identified and the consequences for the optimization of spatial distribution of transmissivity in the groundwater flow model are also addressed.

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