Application of Environmental Isotopes and Hydrochemistry to Identify the Groundwater Recharge in Wadi Qanunah Basin, Saudi Arabia
Round 1
Reviewer 1 Report
Authors studied on Wadi Qanunah Basin identification-characterization and recharding from Quaternary Aquifer. Wadi Qanunah Basin geology and drainge map is rectified on elevation model. Groundwater levels and flow direction map are prepared by measuring 53 well in the basin. EC, temperature and pH were measured for 50 groundwater samples and rain and sea water. Major Ion (Ca-Mg-Na-K-Cl-SO4-HCO3) composition are analysed by labaratuary in addition Nitrate, Silica and Strontioum. However isotopic composition of water (18-Oxygen-Deuterium) are examined in the study. Ionic corelations are given scatter diagrammes and interpreneded. I controll ionic balance of all water and non of them is more than %5, it shows chemical analyses are trustable. High corelation in Na-Cl diagramme are suggested dissolution of halite and high corelation between Ca and SO4 are suggested dissolution of Anhydrite and Gypsum. However temperature column must be added in table-1. Gibbs diagramme proof that evaporation effects all water samples and waterrock interaction are confirmed (halit-gyypsum-anhydrite). Factor analyse were did and more effected parameters water samples are put out. In table-5 saturation index estimated in which temperature and temperature column must be added on table 5.
However disolution, precipitation and ion exchange-reverse ion exchange reaction are determined in order to explain groundwater chemistry, there are no geological-stratigraphical crossection with mineral describtion in formation. It could be usefull. Although Al, B, Fe, Mo, Mn, Ni, Pb, Sr, and Zn analysed, they were not given in Table (Also EC were not given). An addition table including them and coordinates must be added. Also mineral saturation index for suggested minerals in discharge (dynamic) temperrature of wells. From the top of Wadi Qanunah to Red Sea (from NE to SW) a hydrogeological crossection in GIS media must be added a sa conceptual model in order to show flowpath reaction model. In article is called as "Özen, T., Bülbül, A., & Tarcan, G. (2012). Reservoir and hydrogeochemical characterizations of geothermal fields in Salihli, Turkey. Journal of Asian Earth Sciences, 60, 1-17." at fig-9 could be similar. Or in article is called as "Roubil, A., El Ouali, A., Bülbül, A., Lahrach, A., Mudry, J., Mamouch, Y., ... & El Ouali, A. (2022). Groundwater Hydrochemical and Isotopic Evolution from High Atlas Jurassic Limestones to Errachidia Cretaceous Basin (Southeastern Morocco). Water, 14(11), 1747." at fig-11 could be similar. ıwould like to congragulate author for the stuy, it is great original and high scientific study.
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Reviewer 2 Report
I find the paper interesting, scientifically sound, and further justified by a large dataset. It is clear that one of the novelties of the present study is the investigation of possible relations between the characterization of groundwater present based on their chemical and isotopic composition, and discerning the geochemical evolution and mixing processes in the aquifer. The following issues need to be clearly addressed.
1. The NETPATH geochemical program and the WATEQ program need to be clarified. Please add more details about it.
2. In the Materials and methods, Field activities section there is a needs to highlight the present work's overall contribution.
3. In the conclusions paragraph, I suggest that it be summarized in bullet points
4. Finally, please double-check the manuscript for any typo errors throughout the manuscript.
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Reviewer 3 Report
The purpose of the manuscript “sustainability-2123110” are to analyze the major ionic composition of Groundwater in Wadi Qanunah Basin (Saudi Arabia) and identify the natural and/or anthropogenic sources of ions using isotopes, geochemistry and multivariate analysis techniques.
The paper appears well-structured; however, some sections must be improved.
Specific comments (line numbering is missing, so it is difficult to make exact references):
The references are either made with numbers or with names. I recommend standardizing everything with the numbers
Geology should be discussed in more depth, focusing a little more on the petrographic and mineralogical composition of the rocks that make up the aquifers
In figure 1, the writings have too low resolution and cannot be read!
In field activities ,figure 1 is referenced, but it is wrong. Figure 5 should be referred to
In field activities alkalinity and Eh why are missing?
in the representative figure of the boxplots, the minimum and any outliers are missing
The possible origins of the sulphate, which could also derive from sulfides such as pyrite. See for example the work of: (1)
In figure 8 the unit of measurement is not clear...
To evaluate the chemical composition of the water it is not enough to use the Piper diagram because it does not take into account (as proposed by the authors) salinity, I suggest using a TIS salinity diagram, as proposed by:(2)
When we talk about clay minerals, we are referring to biotite, but biotite is not a clay mineral!
When talking about the meteoric water line, reference should be made to Craig 1961:(3)
The dolomite formula is wrong! replace with CaMg(CO3)2
The most critical part of this job is the model! we must start from some considerations: at ambient temperature (weathering) some minerals cannot precipitate for thermodynamic reasons. This is the case with biotite and albite! I advise the authors to read the work of Fuoco et al., 2022:(4)
and to reformulate their model taking into account thermodynamics!
Discussions and conclusions need to be rewritten taking into account previous comments
Recommended works must be added in the bibliography
1. Fuoco, I., De Rosa, R., Barca, D., Figoli, A., Gabriele, B. and Apollaro, C., 2022. Arsenic polluted waters: Application of geochemical modelling as a tool to understand the release and fate of the pollutant in crystalline aquifers. Journal of Environmental Management, 301, p.113796.
2. Apollaro, C., Tripodi, V., Vespasiano, G., De Rosa, R., Dotsika, E., Fuoco, I., Critelli, S. and Muto, F., 2019. Chemical, isotopic and geotectonic relations of the warm and cold waters of the Galatro and Antonimina thermal areas, southern Calabria, Italy. Marine and Petroleum Geology, 109, pp.469-483
3. Craig, H., 1961. Isotopic variations in meteoric waters. Science, 133(3465), pp.1702-1703.
4. Fuoco, I., Marini, L., De Rosa, R., Figoli, A., Gabriele, B. and Apollaro, C., 2022. Use of reaction path modelling to investigate the evolution of water chemistry in shallow to deep crystalline aquifers with a special focus on fluoride. Science of The Total Environment, 830, p.154566.
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Round 2
Reviewer 3 Report
the authors have improved their article.
