Methods for the Geophysical Exploration and Sustainable Utilisation of Coalbed Methane Resources in Abandoned Mines of Shanxi, China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

(1) The reviewer believes that it is necessary to add more quantitative statement of results appropriately in the conclusion and abstract. In this way, the conclusion can be revealed more logically and effectively. Moreover, there is a lack of relevant result statements in the abstract of the manuscript. Therefore, it is recommended that the author carefully revise the abstract.

(2) Some references need to be cited to support the statement in lines 30-32 that "Because of current mining techniques and geological factors, substantial untapped resources persist in abandoned mines such as coal, gas, water and geothermal energy.".  https://doi.org/10.1016/j.oceaneng.2024.117029，https://doi.org/10.1007/s11356-022-19663-4

(3) In the introduction, it is recommended to appropriately summarize the limitations of current relevant research. Because this is a prerequisite for conducting relevant research.

(4) The reviewer suggests adding coordinates and latitude and longitude to Figure 1. Meanwhile, the reviewer suggests providing specific information on the study area in Figure 1.

(5) The several geophysical exploration methods mentioned in the manuscript are commonly used in mining related geological exploration. Moreover, the application research of these methods in coalbed methane exploration has become quite common. So, what are the innovation/highlights of this study?

(6) The quantitative description of the results in the manuscript is seriously lacking. the description of Figure 8 in the manuscript is limited to qualitative explanation, without quantitative description.Therefore, it is recommended to supplement the quantitative explanation of the results obtained from the study.

(7) In Figure 3, why is the black curve in the upper right corner of Figure 3 the coal seam, while other areas are not? What is its basis?

Comments on the Quality of English Language

The language of the manuscript is acceptable, but it requires appropriate checking and polishing.

Author Response

Point-to-point Response to the Referees：

Methods for the geophysical exploration of coalbed methane resources in abandoned mines of Shanxi, China

Response to Reviewer 1

Thank you for your useful comments and suggestions on the language and structure of our manuscript. We have revised the manuscript accordingly, and detailed corrections are listed below point by point:

 

（1） The reviewer believes that it is necessary to add more quantitative statement of results appropriately in the conclusion and abstract. In this way, the conclusion can be revealed more logically and effectively. Moreover, there is a lack of relevant result statements in the abstract of the manuscript. Therefore, it is recommended that the author carefully revise the abstract.

Thank you for your constructive suggestion. The interpretation of geophysical exploration data is based on the qualitative interpretation of anomalies caused by different physical parameters, such as apparent resistivity. Different instruments and parameters will affect the absolute size of the data, but will not affect the relative level of the apparent resistivity value in the normal area and the abnormal area, so the current data interpretation is based on qualitative interpretation. We have revised the abstract of this manuscript. Lines 9- 23

(2) Some references need to be cited to support the statement in lines 30-32 that "Because of current mining techniques and geological factors, substantial untapped resources persist in abandoned mines such as coal, gas, water and geothermal energy." https://doi.org/10.1016/j.oceaneng.2024.117029，https://doi.org/10.1007/s11356-022-19663-4

Thank you for your constructive suggestion, We have added references to support the statement, corresponding to lines 31 and 32.

(3) In the introduction, it is recommended to appropriately summarize the limitations of current relevant research. Because this is a prerequisite for conducting relevant research.

Thank you for your constructive suggestion, We have added the shortcomings of the research status in the introduction, corresponding to lines 64 to 75.

(4) The reviewer suggests adding coordinates and latitude and longitude to Figure 1. Meanwhile, the reviewer suggests providing specific information on the study area in Figure 1.

Thank you for your constructive suggestion, We add longitude and latitude in Figure 1. The geology, coal, and coalbed methane situation in the research area  have been introduced in the article, corresponding to lines 86 to 91, 94 to 95.

 

(5) The several geophysical exploration methods mentioned in the manuscript are commonly used in mining related geological exploration. Moreover, the application research of these methods in coalbed methane exploration has become quite common. So, what are the innovation/highlights of this study?

The purpose of geophysical exploration methods is to detect underground geological conditions, which are widely used in geological exploration and other aspects. In the development and utilization of coalbed methane in abandoned mines, different from geological exploration processes such as mineral exploration, there will be more complex underground geological conditions. For example, the underground exists in multiple layers of goaf stacking, geological data is messy and incomplete, the location of remaining coal resources underground is unclear, the amount of remaining coal resources cannot be accurately calculated, and the geological structure, hydrology, gas, and mining technology conditions of many closed mines cannot be verified. Therefore, how to more accurately detect the geological situation of abandoned mines is a problem worth studying, and it is also the focus of this article.

(6) The quantitative description of the results in the manuscript is seriously lacking. the description of Figure 8 in the manuscript is limited to qualitative explanation, without quantitative description.Therefore, it is recommended to supplement the quantitative explanation of the results obtained from the study.

Thank you for your helpful suggestion, we supplement the quantitative explanation of the results obtained from the study. corresponding to lines 340 to 347.

Thank you for your helpful suggestion, we supplement the quantitative explanation of the results obtained from the study. corresponding to lines 394 to 402.

(7) In Figure 3, why is the black curve in the upper right corner of Figure 3 the coal seam, while other areas are not? What is its basis?

 

Reflection wave detection of coal seams is already very mature, but its detection ability for small hidden goafs, faults, etc. is weak, and diffracted waves have significant advantages in this regard. This figure is a case study of using diffraction waves to detect goaf, demonstrating the feasibility of using diffraction waves to detect goaf. From the figure, it can be seen that there is a thick and continuous black line, which is consistent with the characteristics of seismic waves passing through coal seams in seismic exploration. The coal seams should be continuous, but a fault appears in the middle of the figure, which is consistent with the characteristics of seismic waves passing through goaf.

Thank you very much for your attention and time. Look forward to hearing from you.

Your sincerely,

Chuantao Yu,

1 mar., 2024

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

I have carefully read the paper and found the topic interesting. However, I have some major concerns that need to be addressed before the manuscript can be considered for publication.

Main Concerns:

1. Lack of Prior Geophysical Studies: The manuscript lacks any discussion of pre-existing geophysical studies conducted in the case study areas. A detailed explanation of why such studies were not incorporated or addressed is crucial.

2. Insufficient Justification for Goaf Interpretations: The interpretations of geophysical inversion models as goafs lack context. To substantiate these claims, the authors need to provide detailed information about the geological setting, field observations, and other relevant data.

3. Environmental Issues Omission: The introduction should include a separate paragraph addressing the broader environmental concerns associated with underground coal mining, such as Acid Mine Drainage (AMD) and subsidence.

4. Missing Visuals: The inclusion of photographs showcasing the specific coal basin, mines, and goafs would significantly enhance the manuscript's value for international readers.

5. Conceptual Model: A conceptual model illustrating the mechanism of methane migration from coal layers to goafs would be a valuable addition.

6. Goaf Parameter Influence: Prior to discussing geophysical studies, a flowchart could be added to illustrate how different goaf parameters influence each geophysical method's effectiveness.

7. You must discuss the latest research works which have been done for seismic techniques in detecting the goafs. Cause what you discussed is only for interpretating the seismic methods.

8. Correct the Schlumberger array in the line 265. What kind of array are being used in detecting the goafs? Many papers can be discussed for detecting the goafs, karsts, underground pollution, and so on. Your readers are coming from the world not only Chinese ones! You only mentioned Chinese research works, and you must cite and address other scientific works. You can use AMD delineation form coal waste piles with using geophysical methods such as IP, VLF and DC, time-lapse an so on.

9. If you going to go for theorical relationships, you must bring for all geophysical methods you mentioned in the paper.

 

 

Author Response

Point-to-point Response to the Referees

Methods for the geophysical exploration of coalbed methane resources in abandoned mines of Shanxi, China

Response to Reviewer 2

Thank you for your useful comments and suggestions on the language and structure of our manuscript. We have revised the manuscript accordingly, and detailed corrections are listed below point by point:

1. I have carefully read the paper and found the topic interesting. However, I have some major concerns that need to be addressed before the manuscript can be considered for publication.

We sincerely appreciate your comments, Your professional suggestions are of great significance for improving our paper. Here is our detailed response to your feedback:

2. Lack of Prior Geophysical Studies: The manuscript lacks any discussion of pre-existing geophysical studies conducted in the case study areas. A detailed explanation of why such studies were not incorporated or addressed is crucial.

Thank you for your constructive suggestion, We have added the shortcomings of the research status in the introduction, corresponding to lines 64 to 75.

3. Insufficient Justification for Goaf Interpretations: The interpretations of geophysical inversion models as goafs lack context. To substantiate these claims, the authors need to provide detailed information about the geological setting, field observations, and other relevant data.

Thank you for your helpful suggestion, The geophysical inversion models mentioned in the article are all result graphs from our research project, with the aim of demonstrating the feasibility of their methods. Figures 8 and 10 provide background information and on-site observations. corresponding to lines 340 to 347. and lines 394 to 402.

4. Environmental Issues Omission: The introduction should include a separate paragraph addressing the broader environmental concerns associated with underground coal mining, such as Acid Mine Drainage (AMD) and subsidence.

Thank you for your helpful suggestion, This article mainly discusses the technical support issue of using geophysical methods to develop residual resources in abandoned coal mines, without involving other environmental issues.

5.Missing Visuals: The inclusion of photographs showcasing the specific coal basin, mines, and goafs would significantly enhance the manuscript's value for international readers.

Thank you for your helpful suggestion, We will add images of specific geological conditions in the research area, corresponding to lines 94 to 95.

6. Conceptual Model: A conceptual model illustrating the mechanism of methane migration from coal layers to goafs would be a valuable addition.

 

Thank you for your helpful suggestion, We have added the mechanism model of methane migration from coal layers to goafs, corresponding to lines 134 to 135.

7. Goaf Parameter Influence: Prior to discussing geophysical studies, a flowchart could be added to illustrate how different goaf parameters influence each geophysical method's effectiveness.

Thank you for your helpful suggestion, we have added different goaf parameters influence each geophysical method's effectiveness, corresponding to lines 178 to 185.

8. You must discuss the latest research works which have been done for seismic techniques in detecting the goafs. Cause what you discussed is only for interpretating the seismic methods.

Thank you for your constructive suggestion, We have added the latest seismic exploration research works, corresponding to lines 236 to 250.

9.Correct the Schlumberger array in the line 265. What kind of array are being used in detecting the goafs? Many papers can be discussed for detecting the goafs, karsts, underground pollution, and so on. Your readers are coming from the world not only Chinese ones! You only mentioned Chinese research works, and you must cite and address other scientific works. You can use AMD delineation form coal waste piles with using geophysical methods such as IP, VLF and DC, time-lapse an so on.

Thank you for your constructive suggestion，we have Corrected the Schlumberger device. The Schlumberger device, also known as the symmetrical four level profile method, was widely used in the early development of high-density electrical methods due to its high construction efficiency and good depth measurement effect. Many other device types have also been developed in the future. At present, two or more devices are often used for comprehensive detection of water accumulation in goaf, which is more conducive to the detection of underground media. Meanwhile, we have added more foreign scientific works. corresponding to lines 257 to 260, 302 to 303,312 to 316, et al.

10. If you going to go for theorical relationships, you must bring for all geophysical methods you mentioned in the paper.

There is no research on searching for theoretical relationships in the paper. It is mentioned that the theoretical section only describes the principles of a single method, and it is also mentioned that joint interpretation of multiple methods is more advantageous.

Thank you very much for your attention and time. Look forward to hearing from you.

Your sincerely,

Chuantao Yu,

1 mar.2024

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I think the paper can be accepted for publication now.

Author Response

Thank you for your useful comments and suggestion.

Reviewer 2 Report

Comments and Suggestions for Authors

This is the re-review manuscript entitled “Methods for the geophysical exploration of coalbed methane resources in abandoned mines of Shanxi, China”. I checked all comments carefully, and I found that most of them were addressed properly. However, there are some minor comments as follows:

Please add references to lines 65-76.

The authors must remove local references, Chinese research works, and add much more global references!

Figure 1 is not clear!

Add some pieces of evidence of tunnel faces to the paper. You must ADD some real pictures of the tunnels/mine sites!

Author Response

his is the re-review manuscript entitled “Methods for the geophysical exploration and sustainable utilization of coalbed methane resources in abandoned mines of Shanxi, China”. I checked all comments carefully, and I found that most of them were addressed properly. However, there are some minor comments as follows:

1.Please add references to lines 65-76.

Thank you for your constructive suggestion. we have added references to lines 65-76.

2.The authors must remove local references, Chinese research works, and add much more global references!

Thank you for your constructive suggestion we have added global references, corresponding to lines 57-60,193-195,231-234,

331-332,415-416, et al.

3.Figure 1 is not clear. Add some pieces of evidence of tunnel faces to the paper. You must ADD some real pictures of the tunnels/mine sites!

Thank you for your constructive suggestion, We have modified Figure 1 and added pictures of the mine sites.