Abstract
The hydraulic and hydrogeological features of the Caposele aquifer have been investigated by using a numerical groundwater flow model. In particular, groundwater flow simulations were performed for a multilayered, unconfined aquifer in steady-state conditions for different thicknesses of the aquifer’s saturated zone. The Caposele groundwater model was carried out starting from a generic model drained by a unique spring outlet in accordance with the geo-hydrological features of the study area. The conceptual model was built considering hydrogeological features of spring catchment, and was then implemented with the MODFLOW numerical code. A combined 2D-3D approach was adopted, and the model was calibrated on borehole data available for the time period 2012–2019. Different thicknesses of the aquifer were set, and a reliable relationship was found between the hydraulic head, saturated zone and hydraulic conductivity of the aquifer. Using the MODPATH package, the mean travel time (Darcian) of groundwater was computed for five different scenarios, corresponding to the model’s depths; the analysis that was performed shows that the travel time is higher for a greater and lower for a smaller thickness of the aquifer’s saturated zone, respectively. The Caposele aquifer model was zoned in different sectors, named flow pipe areas, that play different roles in groundwater recharge-discharge processes. A vector analysis was also carried out in order to highlight the ascendant flow near the spring zone.
Highlights
The assessment of groundwater circulation in natural media, which are complex and irregular systems, needs specific hydraulic, hydrogeological and geometric assumptions and simplifications; this assessment can be carried out by resorting to aquifer modelling techniques, based on the use of different geo-informatics tools that allow for the proposition of possible scenarios of groundwater flow.Appl
Emblanch et al [52] exploited chemical and isotopic tracers to evaluate the contribution of different water components discharging at the Fontaine de Vaucluse karst spring near Avignon (Southeastern France), considering two different hydrodynamic phenomena of the aquifers: (i) a perfect piston flow (PF), where each recharge event pushes the previous one towards the hydrological outlet; (ii) a well-mixed model (WMM), where the discharged water is a mixture between all aquifer components [52,53]; the aforementioned systems point out two extreme flow modalities; in nature in particular, the majority of aquifers highlight an intermediate behavior between the PF and
The numerical simulation performed for the Caposele aquifer relies on the boundary conditions of the conceptual model subsequently implemented with the MODFLOW numerical code
Summary
The assessment of groundwater circulation in natural media, which are complex and irregular systems, needs specific hydraulic, hydrogeological and geometric assumptions and simplifications; this assessment can be carried out by resorting to aquifer modelling techniques, based on the use of different geo-informatics tools that allow for the proposition of possible scenarios of groundwater flow.Appl. The assessment of groundwater circulation in natural media, which are complex and irregular systems, needs specific hydraulic, hydrogeological and geometric assumptions and simplifications; this assessment can be carried out by resorting to aquifer modelling techniques, based on the use of different geo-informatics tools that allow for the proposition of possible scenarios of groundwater flow. The investigation of karst aquifers is not easy to carry out due to the complexity and heterogeneity of such natural systems, where groundwater circulation occurs through a well-structured net of cave and conduits [1]. As the karst system is characterized by extreme types of porosity, connected to the presence of voids of different sizes, from the matrix to the conduit/cave systems [2], the Darcy law can be applied to the flow system into the matrix portion, whereas it becomes hardly achievable in aquifers that are strongly fractured and affected by a highly developed net of conduits/shafts, which need different approaches. The tool which better simulates the groundwater flow for the saturated zone, at a regional and subregional scale [3], is the MODFLOW numerical code [4,5,6], which allows one to assess the flow path, calibrating the simulated hydraulic parameters on the observed data
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
