Prediction of the Water Inrush Risk from an Overlying Separation Layer in the Thick Overburden of a Thick Coal Seam

Round 1

Reviewer 1 Report

sustainability-2565037-review

Based on the study background of the double-layer structure characteristics of the roof rock of the 2-2 coal seam in the 221 mining area of the Shilawusu Coal Mine in the Ordos coalfield, this paper selected the core recovery rate of the key aquiclude, the lithologic assemblage index of the key aquiclude, the key aquiclude thickness, the lithologic structure index of the Zhidan Formation, and the hydrostatic head as the evaluation indexes of the separation layer water inrush risk. The hydrogeological model is established by means of subjective and objective weights and the improved catastrophe progression method, which has certain guiding significance for solving the risk assessment of water inrush from high strata. This is an interesting and valuable topic. However, there are still some small problems in the manuscript, the following suggestions may be helpful to improve the quality of the manuscript, as follow:

1．In Figure 1, please add one scale to the Map of China. The color of the lines in the schematic diagram of the research area in Figure 1 is not clear enough.

2．Suggest explaining or deleting H_W and H_F in Figure 4.

3．It is recommended to rearrange Figures 5 to 9, and putting them together may have a better layout effect.

4．The text font in Figure 10 is recommended to be consistent with the other figures.

5．It is recommended to unify the formula format in the paper.

6．Some parameters and subscript formats in the paper are inconsistent, it is recommended to modify them to the same format.

7．Suggest adding and citing references from relevant fields in recent years.

The manuscript can be accepted after careful revision.

 Moderate editing of English language required

Author Response

Dear reviewer:

Thank you for your concerning our manuscript entitled “Prediction of the Water Inrush Risk from an Overlying Separation Layer in the Thick Overburden of a Thick Coal Seam” (ID: sustainability-2565037). Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper. 

Comments:

1. In Figure 1, please add one scale to the Map of China. The color of the lines in the schematic diagram of the research area in Figure 1 is not clear enough.

Response:We increased the scale of the map and adjusted the color of Figure 1

2. Suggest explaining or deleting H_Wand H_F in Figure 4.

Response: H_W and H_F are deleted.

3. It is recommended to rearrange Figures 5 to 9, and putting them together may have a better layout effect.

Response:We modified Figures 5-9 to make them a group.

4. The text font in Figure 10 is recommended to be consistent with the other figures.

Response:We changed Figure 10 and the text format.

5. It is recommended to unify the formula format in the paper.

Response:Modified.

6. Some parameters and subscript formats in the paper are inconsistent, it is recommended to modify them to the same format.

Response:Modified

7. Suggest adding and citing references from relevant fields in recent years.

Response:According to the suggestion, we cited some references in recent years.

Special thanks to you for your good comments.We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper. And we marked in red in revised paper.

We appreciate for Editors and Reviewers' warm work earnestly，and hope that the correction will meet with approval.

Once again, thank you very much for your comments and suggestions.

Yours sincerely,

Chenghao Han

Reviewer 2 Report

The manuscript deals with the issue of the water inrush risk through the overburden layer of a coal seam, which constitutes a possible hazard to the safety of mining operations. The hydrogeological issues of a mining area are related to other issues, such as environmental and geotechnical issues and constitute, in general, a critical aspect of the total mining conditions. In this framework, emphasis is placed on the possible water hazards to prevent from causing casualties during mining operations.

The approach the authors of the manuscript adopt focuses on specific indices and their interrelationships. The authors have done remarkable work, and the results are very interesting and valuable, considering the criticality of the investigated issue. However, the investigated issue needs to be supported and documented adequately, and the manuscript needs to be improved in several parts.

Furthermore:

- The English language and syntax must be improved throughout the manuscript. The style of writing is relatively informal in several parts of the manuscript. In addition, in several parts, the whole manuscript is written like a technical report, not an original scientific article. Therefore, it needs to be highly improved.

- It is suggested to use different words than the title for keywords. The "overlying separation layer" exists already in the title.

- Are both "overlying separation layer" and the "thick overburden" needed in the title?

- From an engineering point of view, the practical considerations of the research should be further discussed.

- Compared to other previous works, the original contribution of the work needs to be presented.

- It is suggested to create a flowchart with the methodology followed.

- The symbols in the equations should be the same as in the text.

- Please use the style of the journal's template and the references style. What exactly shows the [J] in "References"?

- Figures 3 and 4 could be smaller.

Abstract

General note: The abstract adequately describes the investigated issue and the developed methodology, but the results must be briefly mentioned.

1. Introduction

General comment: In this section of the manuscript, the following need to be added:

a) the innovative contribution of the manuscript and b) the research questions that are aimed to be configured. Instead, in the last paragraph, there is a repetition regarding the indices used for evaluation.

[Lines 37-41] A better description of the events is needed in more complete sentences.

[Line 43] A new paragraph should start with "At present…"

2. Materials and Methods

General note:

·   The subsection "2.1 Geological situation" could be renamed "2.1 Geological setting".

·   In addition, is there a need for subsection 2.2 to stand alone separately from the 2.1? Both regard geological settings.

·   Please explain how the maps of Figures 5-9 were derived. With which method/technique? Also, scales should be added.

[Lines 96-102] The description of the stratigraphy should be presented by combining Table 1 with a stratigraphic column or by combining it with the stratigraphic column of Figure 2. As the stratigraphic column already exists, the symbols of the formations mentioned in the text could be added near each stratum in the column of Figure 2.

[Line 104] The map legend in Figure 1 is not comprehensive. Please use more distinct symbolization. A scale and coordinates reference system need to be added.

[Line 106] "…which is located…" instead of "…which are located…"

[Line 107] "…study area…" instead of "…research object…"

[Line 110] Which is the coal seam 2?

[Line 117] "…are relatively obvious" How the mechanical properties of the formation are relatively obvious?

[Line 124] Characteristic range values of the mechanical properties of the formations should be added to the description from the literature or laboratory tests.

[Line 126] “Based on the differences ……………..in the study area”: What are the differences?

[Fig 2] Units of the thicknesses of the strata should be added to Figure 2. In the footing of the figure, a better description of what is depicted is needed.

[Lines 136-138] This sentence needs to be improved.

[Line 185] Figure 5: "Rate of adoption"? Please check.

[Line 221] Figure 7: Please add units (m) near the "thickness" in the legend.

[Lines 231-233] "The water…layer water" The sentence should be rewritten to be comprehensive.

[Line 245] Figure 8: Please add units (m) near the "lithologic structure index" in the legend.

[Line 261] Please explain why these specific 47 boreholes were selected and further describe the procedure. Subsection 2.3.6 and Table 3 have a very short description.

[Line 265] Subsection 2.4 has an informal writing style by suddenly numbering the steps followed. An introduction and a more adequate description of the procedure are needed.

[Lines 297, 299, 301, 303] "Calculate"? Like an order?

[Lines 312-315] The sentence needs to be improved to be comprehensive.

3. Results and Discussion

General note: This section is not adequately described. It is like a simple citation of the results in Tables.

[Line 347-348] Figure 10 could be moved to the "Materials and Methods" Section.

[Line 402] Which is the "natural classification"? Here is the first time it is mentioned. Please explain.

[Line 408] Please describe how the map of Figure 11 was derived.

4. Conclusions

General note: This section needs to be extensively improved. Please describe the main conclusions formally and not like a technical report. The innovative contribution of the research needs to be noticed, and suggestions about further research must be mentioned.

 

 

 

 

 

 

The English language and syntax must be improved throughout the manuscript. The style of writing is relatively informal in several parts of the manuscript. In addition, in several parts, the whole manuscript is written like a technical report, not an original scientific article.

Author Response

Dear reviewer:

Thank you for your concerning our manuscript entitled “Prediction of the Water Inrush Risk from an Overlying Separation Layer in the Thick Overburden of a Thick Coal Seam” (ID: sustainability-2565037). Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper. 

Comments:

1. The English language and syntax must be improved throughout the manuscript. The style of writing is relatively informal in several parts of the manuscript. In addition, in several parts, the whole manuscript is written like a technical report, not an original scientific article. Therefore, it needs to be highly improved.

Response:As for the language and style problems of this paper, we have made corresponding modifications according to the problems pointed out later, and have described and enriched some chapters and sentences to make it a paper with correct format.

2. It is suggested to use different words than the title for keywords. The "overlying separation layer" exists already in the title.

Response:We have deleted the keyword "overlying separation layer".

3. Are both "overlying separation layer" and the "thick overburden" needed in the title?

Response:We believe that "thick overburden" is used to explain the geological background conditions of the research problem, and "overlying separation layer" is used to indicate the height of the development position of the stratosphere. Both of them can better reflect the research content and significance of our paper.

4. From an engineering point of view, the practical considerations of the research should be further discussed.

Response：We further consider the practical considerations of the study.

5. Compared to other previous works, the original contribution of the work needs to be presented.

Response：In the introduction, we have improved the relevant content to better express our original contribution.

6. It is suggested to create a flowchart with the methodology followed.

Response：According to your suggestion, we have made a flowchart and put it at the end of section 2.5.

7. The symbols in the equations should be the same as in the text.

Response：We checked the symbols in the full text formula and the symbols in the text, and corrected the inconsistent symbols.

8. Please use the style of the journal's template and the references style. What exactly shows the [J] in "References"?

Response：We checked the format of the reference, and revised [J] according to the format.

Figures 3 and 4 could be smaller.

Response：We resized Figures 3 and 4.

Abstract

9. The abstract adequately describes the investigated issue and the developed methodology, but the results must be briefly mentioned.

Response：We have made appropriate changes to the summary and the results can also be mentioned.

1. Introduction

General comment: In this section of the manuscript, the following need to be added:

10. the innovative contribution of the manuscript and b) the research questions that are aimed to be configured. Instead, in the last paragraph, there is a repetition regarding the indices used for evaluation.

Response：We have made necessary changes to the introduction. We have deleted repeated references to the evaluation of indicators and redescribed the innovative contributions and research problems to better reflect the above two points.

11. [Lines 37-41] A better description of the events is needed in more complete sentences.

Response：We have revised the description of the event to indicate the hazards of the layer separation water.

12. [Line 43] A new paragraph should start with "At present…"

Response：Modified as suggested.

2. Materials and Methods
3. General note:

   The subsection "2.1 Geological situation" could be renamed "2.1 Geological setting".

   In addition, is there a need for subsection 2.2 to stand alone separately from the 2.1? Both regard geological settings.

   Please explain how the maps of Figures 5-9 were derived. With which method/technique? Also, scales should be added.

Response：(1)The subsection "2.1 Geological situation" is renamed "2.1 Geological setting".

（2）Subsections 2.2 and 2.1 are combined into one section.

（3）Figures 5-9 are drawn by surfer software, and the data are drawn from the data drawn in Table 3. We have modified the original Figure 5-9, made it into a group figure and added the scale.

14. [Lines 96-102] The description of the stratigraphy should be presented by combining Table 1 with a stratigraphic column or by combining it with the stratigraphic column of Figure 2. As the stratigraphic column already exists, the symbols of the formations mentioned in the text could be added near each stratum in the column of Figure 2.

Response：We have modified the stratigraphic symbols in Table 1 and the stratigraphic symbols in Figure 2 have been modified and added.

15. [Line 104] The map legend in Figure 1 is not comprehensive. Please use more distinct symbolization. A scale and coordinates reference system need to be added.

Response：We added the scale and coordinate system.

16. [Line 106] "…which is located…" instead of "…which are located…"

Response：Modified.

17. [Line 107] "…study area…" instead of "…research object…"

Response：Modified.

18. [Line 110] Which is the coal seam 2?

Response：coal seam 2 has been modified to 2-2 coal seam.

19. [Line 117] "…are relatively obvious" How the mechanical properties of the formation are relatively obvious?

Response：The mechanical properties of rock strata are relatively obvious in comparison with the Chalk Zhidan Group. We have modified this sentence.

20. [Line 124] Characteristic range values of the mechanical properties of the formations should be added to the description from the literature or laboratory tests.

Response：The mechanical properties mentioned in this paper are the relative ratio of two groups of strata, and the difference of characteristic values is reflected by the comparison.

21. [Line 126] “Based on the differences ……………..in the study area”: What are the differences?

Response：The differences mentioned in our article refer to the differences in the description of rock mechanics and rock beam combination in the previous two paragraphs.

22. [Fig 2] Units of the thicknesses of the strata should be added to Figure 2. In the footing of the figure, a better description of what is depicted is needed.

Response：The description of Figure 2 has been modified.

23. [Lines 136-138] This sentence needs to be improved.

Response：The sentences have been improved.

24. [Line 185] Figure 5: "Rate of adoption"? Please check.

Response：Core recovery rate instead Rate of adoption.

25. [Line 221] Figure 7: Please add units (m) near the "thickness" in the legend.

Response：Modified.

26. [Lines 231-233] "The water…layer water" The sentence should be rewritten to be comprehensive.

Response：Modified.

27. [Line 245] Figure 8: Please add units (m) near the "lithologic structure index" in the legend.

Response：Modified.

28. [Line 261] Please explain why these specific 47 boreholes were selected and further describe the procedure. Subsection 2.3.6 and Table 3 have a very short description.

Response：These 47 boreholes are evenly distributed in the mining area, and the borehole data can reflect the index characteristics well.

29. [Line 265] Subsection 2.4 has an informal writing style by suddenly numbering the steps followed. An introduction and a more adequate description of the procedure are needed.

Response：Numbers have been removed and expressions have been added to each step.

30. [Lines 297, 299, 301, 303] "Calculate"? Like an order?

Response："Calculate" has been removed and representations added to each step.

31. [Lines 312-315] The sentence needs to be improved to be comprehensive.

Response：The sentences have been improved.

3. Results and Discussion
4. General note: This section is not adequately described. It is like a simple citation of the results in Tables.

Response：In this part, we mainly describe the calculation process and results of ahm, coefficient of variation method and mutation series method. Therefore the main process is reflected in the form of tables.

33. [Line 347-348] Figure 10 could be moved to the "Materials and Methods" Section.

Response：Figure 10 has been moved to the "Materials and Methods" Section.

34. [Line 402] Which is the "natural classification"? Here is the first time it is mentioned. Please explain.

Response：natural classification is also called natural breakpoint method.Paragraph-point method is a method that classifies data sets based on discontinuous places in data sets.

35. [Line 408] Please describe how the map of Figure 11 was derived.

Response：We use surfer software to draw the mutation level values calculated by each borehole above.

4. Conclusions
5. General note: This section needs to be extensively improved. Please describe the main conclusions formally and not like a technical report. The innovative contribution of the research needs to be noticed, and suggestions about further research must be mentioned.

Response：We have revised the conclusions to describe the innovative contributions mentioned in the recommendations and the recommendations for further research.

Special thanks to you for your good comments.We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper. And we marked in red in revised paper.

We appreciate for Editors and Reviewers' warm work earnestly，and hope that the correction will meet with approval.

Once again, thank you very much for your comments and suggestions.

Yours sincerely,

Chenghao Han

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The manuscript has been significantly improved in the revised version, and I believe that it warrants publication.

Moderate editing of the English language required