Hydrogeophysical Study of Sub-Basaltic Alluvial Aquifer in the Southern Part of Al-Madinah Al-Munawarah, Saudi Arabia

Round 1

Reviewer 1 Report

The work of Metwaly et al. proposes to evaluate the sub-basaltic alluvial aquifer in the northern part of Harrat Rahat, Southern of Al-Madinah city, and then estimates the essential aquifer hydraulic parameters based on the interpreted 1D resistivity-depth models.

The title reflects the content of the article.

The abstract should be made in a more concise manner

The article needs to be made accordingly to the journal format, I can not see a Material and Methods section

A clear methodology has to be stated as well as conclusions and discussions

Author Response

Reviewer 1:

Comments and Suggestions for Authors

The work of Metwaly et al. proposes to evaluate the sub-basaltic alluvial aquifer in the northern part of Harrat Rahat, Southern of Al-Madinah city, and then estimates the essential aquifer hydraulic parameters based on the interpreted 1D resistivity-depth models.

The title reflects the content of the article.

The abstract should be made in a more concise manner

The abstract has been modified and enhanced

The article needs to be made accordingly to the journal format, I can not see a Material and Methods section

A clear methodology has to be stated as well as conclusions and discussions

Methodology section has been added to categorize most of the manuscript parts relating to methodology.

Concussions and discussion sections have been added.

Reviewer 2 Report

The manuscript “Hydrogeophysical study of sub-basaltic alluvial aquifer in the southern part of Al-Madinah Al-Munawarah, Saudi Arabia” represents an interesting case study in which VES’s sounding is used to characterize an aquifer. I acknowledge the effort made by the authors to prepare the manuscript, however, in my opinion, major revisions are needed. The first important point is to improve the structure of the manuscript. In fact, it does not show the methodology in a separated section, while it is mixed with other sections (see the following comments). The results are poorly presented, and there is no discussion. The reader cannot easily match the objective of the research with the results and the results’ presentation should be improved. The figures are of low quality and need to be updated, and some of them can be omitted. Furthermore, the title of the paper is very general, and I suggest to be more specific. I suggest restructuring the paper to have (abstract, introduction, methodology, results, discussion, and conclusion). Sections 3 and 4 describe the study area and they can be part of the study area section as subsections (2.1 and 2.2). Considering some technical aspects, I would expect a more in depth discussion about how the salinity affects the measurements and I think the analysis of Figure 11 are wrong. The figure does not compare estimated and VES data. On the x-axis indeed we have the number of data points. Moreover, the correlation coefficient is very low.

Finally, since the journal is called sustainability, I would expect in the introduction a stronger link to this topic. For example, the authors could comment about how their work fits in the governmental policies for sustainable groundwater development (see for example Alqadi, Mohammad, Ala Al Dwairi, Sudeh Dehnavi, Armin Margane, Marwan Al Raggad, Mohammad Al Wreikat, and Gabriele Chiogna. 2021. "A Novel Method to Assess the Impact of a Government’s Water Strategy on Research: A Case Study of Azraq Basin, Jordan" Water 13, no. 15: 2138. https://doi.org/10.3390/w13152138).

Please find more detailed comments below:

1. 40-44: The three sentences need to be connected in a better way that shows the importance of the evaluation of groundwater (GW) resources.

 

is it important to evaluate the GW resources because of the extensive pumping or because it is located in arid-semi arid area or both of them?

 

please add a reference for line 44

 

this part should be moved to the study area section with the figures, in fact, I find it strange to have figures in the introduction.

 

2. 41 Do you mean the Fossil GW by “it is “? if yes, I suggest " the fossil groundwater is located ..."

 

3. the y axis title needs to be modified for both graphs i suggest "consumption rate [MCM]"

x axis title in small letter

add Figure 1.a and Figure1.b

add the unit to the caption as well. I suggest:

" Figure 1. The rate of water consumption in Million Cubic Meter (MCM) in (a) Saudi Arabia and (b) the main cities.

 

4. 57 - 61 reference missing
5. 63-66: the reason that makes "... the electrical resistivity more accurate method that can be applied ..." is not clear
6. 72-80: the paragraph should be in the methodology section
7. 81-85: to be added to study area
8. 91-101: this paragraph represent the objectives of the study , however the results don’t match what is this intending goals maybe the results needs to be represented in a way that match the objectives
9. 11-13 reference is missing
10. The section 3.geological settings should be part of the study area section
11. 144: section 4. Hydrology is too detailed . I believe that part of the presented information can be used later in the result part, where you can compare your results with the previous findings

also this can’t be a section by itself. It describes the study area

12. 145 -147: some of the information is already mentioned in the previous section. as I recommended in the previous comment this should be part of the study area section
13. fig 4: the graphs are not necessary (to be removed), in case you prefer to keep them, I recommend at least that these graphs will be labeled (a, b) in the figure and caption.

also the cross section lines need to be labeled and matched with the elevation graphs

14. Fig 5: is this your result? if yes , please make it clearer and add it to the result section
15. 218-219 “ located along……” repeated info
16. 220-229 : this paragraph is describing the methodology. it should be part of the methodology .. so I recommend to add Methodology section to the paper and include such information
17. 234-244 : this should be in the methodology
18. 245-254: this should be in the result section
19. 255-257: "To confirm ... are examined " to be added to the methodology
20. 257- 268 : should be in the result part
21. 257: is this a result or a general statement? if it is part of you results , the sentence should be modified for example " most of the produced by this study started.....etc"
22. figure 7 : please describe in the caption the figures a-e. the lines are in figures cant be read, for example figure 7.c all the lines are overlapped
23. the section 7 to be added to the result section
24. Figure 10 x axis labels are missing, in the caption add please the a, b and c description
25. 316 - 379 is describe the method , it can be summarized and added to the methodology section
26. 380- 399 : should be part of the result
27. the conclusion states some results that are not mentioned in the body of the paper. the paper needs to be restructured ( discussion section is needed before the conclusion).

Author Response

Reviewer 2:

Comments and Suggestions for Authors

The manuscript “Hydrogeophysical study of sub-basaltic alluvial aquifer in the southern part of Al-Madinah Al-Munawarah, Saudi Arabia” represents an interesting case study in which VES’s sounding is used to characterize an aquifer. I acknowledge the effort made by the authors to prepare the manuscript, however, in my opinion, major revisions are needed. The first important point is to improve the structure of the manuscript. In fact, it does not show the methodology in a separated section, while it is mixed with other sections (see the following comments). The results are poorly presented, and there is no discussion. The reader cannot easily match the objective of the research with the results and the results’ presentation should be improved. The figures are of low quality and need to be updated, and some of them can be omitted. Furthermore, the title of the paper is very general, and I suggest to be more specific. I suggest restructuring the paper to have (abstract, introduction, methodology, results, discussion, and conclusion). Sections 3 and 4 describe the study area and they can be part of the study area section as subsections (2.1 and 2.2). Considering some technical aspects, I would expect a more in depth discussion about how the salinity affects the measurements and I think the analysis of Figure 11 are wrong. The figure does not compare estimated and VES data. On the x-axis indeed we have the number of data points. Moreover, the correlation coefficient is very low.

Finally, since the journal is called sustainability, I would expect in the introduction a stronger link to this topic. For example, the authors could comment about how their work fits in the governmental policies for sustainable groundwater development (see for example Alqadi, Mohammad, Ala Al Dwairi, Sudeh Dehnavi, Armin Margane, Marwan Al Raggad, Mohammad Al Wreikat, and Gabriele Chiogna. 2021. "A Novel Method to Assess the Impact of a Government’s Water Strategy on Research: A Case Study of Azraq Basin, Jordan" Water 13, no. 15: 2138. https://doi.org/10.3390/w13152138).

The general manuscript structures have been modified, adding the material and methodology section to categorize the parts relating to this section. 

The discussion section has been added with emphasizing the results of the work.

The figures uploaded in the revised version are in high quality and all individual comments have been addressed.

The main aims of the research article are clear (sub-basaltic aquifer properties and estimating the aquifer hydraulic parameters). These two objectives are rather away from studying the salinity variation of the groundwater on the VES data. This is another research point that out of the current scope.

The introduction section has been modified emphasizing the importance of groundwater sustainability to governmental projects and the importance to getting the aquifer parameters for future aquifer developments.

Figure (11): Is correct and display the (a) comparison between the calculated transmissivity from pumping test experiments and those estimated from the VES model data sets.

The wide range of transmissivity values are referring to the heterogeneity of the sub-basaltic aquifer. This heterogeneity affects the estimated values as well. Whatever the label of (x) axis, the correlation between the two data sets is reasonable. It is not possible to decrease the correlation factor.

In fig. (11b) the relation between the traverse resistivity and transmissivity is clear and also the wide range of transmissivity is referring to the aquifer heterogeneity.

Please find more detailed comments below:

1. 40-44: The three sentences need to be connected in a better way that shows the importance of the evaluation of groundwater (GW) resources.

 The three sentences have been modified and connected.

is it important to evaluate the GW resources because of the extensive pumping or because it is located in arid-semi arid area or both of them?

 The reasons and goals for carrying out this research were modified to be clear.

please add a reference for line 44

The reference has been added.

this part should be moved to the study area section with the figures, in fact, I find it strange to have figures in the introduction.

 The figures have been moved to “study area” section.

1. 41 Do you mean the Fossil GW by “it is “? if yes, I suggest " the fossil groundwater is located ..."

 It has been corrected

1. the y axis title needs to be modified for both graphs i suggest "consumption rate [MCM]"

x axis title in small letter 0add Figure 1.a and Figure1.b add the unit to the caption as well.

I suggest:" Figure 1. The rate of water consumption in Million Cubic Meter (MCM) in (a) Saudi Arabia and (b) the main cities.

 All comments have been addressed.

1. 57 - 61 reference missing

Suitable reference has been added.

1. 63-66: the reason that makes "... the electrical resistivity more accurate method that can be applied ..." is not clear

This sentence has been rewritten.

1. 72-80: the paragraph should be in the methodology section

Now it comes under material and methodology section.

1. 81-85: to be added to study area

This is a general description for the surface and aquifer characteristics and why this work is not easy to achieve, therefore it comes in the introduction section.

More details about the study are and detailed properties are coming in the “study area” section.

1. 91-101: this paragraph represent the objectives of the study , however the results don’t match what is this intending goals maybe the results needs to be represented in a way that match the objectives

I totally disagree this reviewer comment, all the defend goals and objects have been achieved through the data analysis and interpretation of the data sets. More description about the achieved results have been addressed in the Geoelectrical data processing- and Estimating of the aquifer hydraulic parameters sections and general outline has been clearly outlined in the “discussion” section.

1. 11-13 reference is missing

It is not common to add a references in the abstract section, particularly this sentence is general statement about the aquifer parameters.

1. The section 3.geological settings should be part of the study area section

The properties of the study area are rather differing than the geological setting, therefore they came in two separate sub-sections. Joining the two section will not add any value to the manuscript.

1. 144: section 4. Hydrology is too detailed . I believe that part of the presented information can be used later in the result part, where you can compare your results with the previous findings

also this can’t be a section by itself. It describes the study area

The “Hydrology” section has to be described in details, this is essential to introduce a clear understanding for the subsurface aquifers. It is not logical sequence to move all the detailed information in the result section. Moreover, the results are essentially referring and comparing with the basic hydrology information.

1. 145 -147: some of the information is already mentioned in the previous section. as I recommended in the previous comment this should be part of the study area section

No way to be away from stated the classification of the subsurface aquifers in two or more sections. This is not a repeated information.

 

1. fig 4: the graphs are not necessary (to be removed), in case you prefer to keep them, I recommend at least that these graphs will be labeled (a, b) in the figure and caption. also the cross section lines need to be labeled and matched with the elevation graphs

I prefer to keep (fig. 4) and the labels (a to d) have been added.

 

1. Fig 5: is this your result? if yes , please make it clearer and add it to the result section

The figure (5) modified and the suitable reference has been added. It is not possible to move it to result section as it is not a result.

 

1. 218-219 “ located along……” repeated info

It is not repeated information but description where the geophysical measurements have been conducted.

1. 220-229 : this paragraph is describing the methodology. it should be part of the methodology .. so I recommend to add Methodology section to the paper and include such information

Material and methodology title has been added to categorize the sub-sections that are dealing with the methodology. There are two wide methods in this work, geoelectric resistivity and hydrology, therefore the both methods should have two subtitle.

1. 234-244 : this should be in the methodology

This part is dealing with the processing of the VES data sets, it cannot be shifted to methodology.

1. 245-254: this should be in the result section

Also, this part is relating to processing section rather than result, therefore I prefer to keep it in the processing section.

1. 255-257: "To confirm ... are examined " to be added to the methodology

This part is not related to methodology, this is analysis of the VES curves as it is important to understand the curve character to get accurate results. So it is related to processing section.

1. 257- 268 : should be in the result part

This part cannot be moved to results, because it is explaining the curve characters that are essential in processing technique of VES data.

1. 257: is this a result or a general statement? if it is part of you results , the sentence should be modified for example " most of the produced by this study started.....etc"

Again this is a description for the curve character and how it can be converted to geoelectric resistivity layers. This is not a result, but essential step in the processing sequence.

The same sentence has three comments, however it is in the right place and meaning.

1. figure 7 : please describe in the caption the figures a-e. the lines are in figures cant be read, for example figure 7.c all the lines are overlapped

The sub-figures (a-e) have been added to figure caption. The figure shows the different curves character of the acquired VES data, the reading of the individual curves has not essential contribution. Only the general curve characters are intended, however the thickness of the curves has been reduced to make the curves clearer.

1. the section 7 to be added to the result section

In the geoelectrical resistivity work, the description of the cross-section means the results but in more specified meaning. The cross-section is one of the basics to the hydraulic parameters estimation, Therefore, it comes in separate “section”.

1. Figure 10 x axis labels are missing, in the caption add please the a, b and c description

The missing labels have been added and figure caption has been modified.

1. 316 - 379 is describe the method , it can be summarized and added to the methodology section

This part is essential to explain before the calculations of aquifer hydraulic parameters and cannot be moved away from this part.

1. 380- 399 : should be part of the result

This part comes under the section “Estimating of the aquifer hydraulic parameters” which is appropriate with the main context of the manuscript sequence. It has no meaning to move elsewhere.

1. the conclusion states some results that are not mentioned in the body of the paper. the paper needs to be restructured ( discussion section is needed before the conclusion).

Most of the manuscript sections have been modified and the recommended section succession have been addressed. Most of the results are discussed under “discussion” section.

Reviewer 3 Report

1. First of all, I feel the topic of this research is not well suited to Sustainability Journal. It is more suited to Hydrology or Water Journal because author did not mention importance of this kind of research and with sustainable management of water resources.   I don't find any uniqueness here.

 2. Whole manuscript is poorly written and lots of issues with the English grammar, hence authors are suggested to revise it thoroughly.

3. In methodology section, author must mention about the equations they have used to calculate the apparent resistivity.  

Comments for author File: Comments.pdf

Author Response

Reviewer 3:

Comments and Suggestions for Authors

1. First of all, I feel the topic of this research is not well suited to Sustainability Journal. It is more suited to Hydrology or Water Journal because author did not mention importance of this kind of research and with sustainable management of water resources.   I don't find any uniqueness here.

More details about the groundwater parameters for sustainable developments have been added to different manuscript sections.

The manuscript subject is strongly related to groundwater sustainable development that is fit well with the journal aims.

2. Whole manuscript is poorly written and lots of issues with the English grammar, hence authors are suggested to revise it thoroughly.

The whole manuscript is intensively reviewed for English grammar and sentences structure.

3. In methodology section, author must mention about the equations they have used to calculate the apparent resistivity.  

The equations that are applied in apparent resistivity are found in most all the text books relating to ER method, adding such theoretical basis will not contribute with any vital addition information for the readers.

 

Round 2

Reviewer 1 Report

The authors have addressed the previous stated and I find the article now suitable for publication

Author Response

Thanks for the reviewer recommendation to accept the manuscript.

Reviewer 2 Report

The authors unfortunately have not been able to address properly all the concerns presented in my previous review. While they did a good job in improving the figures, other aspects are still poor. In particular, they should better structure the methods part and divide it from the results part. Moreover, the authors should better explain 1. why the number of data point should impact the transmissivity of the aquifer (Figure 11a) and 2. why they can exclude any influence of the salinity of the aquifer on the inversion that they perform.

Author Response

• The manuscript structure has been considered and the methodology section has been added and separated from the results.
• In the previous version of Fig. 11a, to compare the consistency of the estimated and measured transmissivity, the (x-axis) was denoted with No. of data points (just as a fixed scale for both data sets.
• In the modified version the figure has been modified and the relation is now between the estimated and measured transmissivity, however this relation shows only the comparable data points which are (8) points only. The estimated (T) values for all the VES models are plotted in comparison with the traverse resistivity (Fig. 11b).
• To consider the salinity of the aquifer in this study, water samples analysis should be included and this is out of this research scope. Even so, it will not affect the general purpose of the manuscript. Therefore, it is not included in this work, however, the effect of increasing the groundwater salinity was included in other research work (Hydrochemical and Quality Assessment of Groundwater Resources in Al-Madinah City, Western Saudi Arabia, Sustainability 2020, 12, 3106; doi:10.3390/su12083106).

Reviewer 3 Report

I didn't find the appropriate response from the authors to address the comments or concern. I still feel methodology section must be more elaborated before it can be accepted for publication. 

 

 

Author Response

The manuscript construction has been reconsidered and methodology section has been added.

Round 3

Reviewer 3 Report

Based on the revision made by the authors, I recommend for its publication.