A Comprehensive Classification Method for the Pore Permeability of Deep-Mine Sandstone Used to Guide Grouting
Victor N. Balashov
Round 1
Reviewer 1 Report
Comments:
1. Good paper, however, the English language needs a lot of improvement.
Author Response
Response to reviewer 1’s comments
We are very grateful to you for your valuable suggestions on revising the manuscript. Our replies are detailed below.
Point 1 Good paper, however, the English language needs a lot of improvement.
Reply: To improve the English language of this manuscript, AJE’s premium editing service has been completed on this revised version once more.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
There is a need in a serious revision of Subsection 3.1 (Pore structure).
1. What is the meaning of "intergranular secondary dissolved pores"? What understand authors under "dissolved pore"? What is the meaning of "residual primary pores"? "residual intergranular pores"?
2. It is very difficult to find correspondence between Figures 5a - 5n and captions to Figure 5.
3. Unequivocal definitions of different types of pores must be formulated.
4. What is the meaning of Column "Representative type" in the Table 9? It is very vague.
5. The English requires a moderate changes in some places and word usage. For example, lines 453-454, "PAPER CAN evaluate the grouting difficulty and propose ...". It might seem unnecessary "So" (line 494 ) and "For example" (line 496).
Author Response
Response to reviewer 2’s comments
We are very grateful to you for your valuable suggestions on revising the manuscript. Our replies are detailed below (please note the underlined text that indicates the position of the modified part in the manuscript).
Point 1- What is the meaning of "intergranular secondary dissolved pores"? What understand authors under "dissolved pore"? What is the meaning of "residual primary pores"? "residual intergranular pores"?.
Reply: Yes, some translation errors in subsection 3.1 (pore structure), such as "intergranular secondary dissolution pore", "dissolution pore" and "residual primary pore", make it very difficult to understand the our viewpoint. To solve these professional translation errors, on the basis of careful investigation and extensive consultation with sedimentological experts, we have clarified the definitions of different types of pores, and AJE editors have revised the whole of subsection 3.1 again (see subsection 3.1 "Pore Structure").
Point 2- It is very difficult to find correspondence between Figures 5a - 5n and captions to Figure 5.
Reply: The key information of the caption to Figure 5 has been moved to the corresponding picture for easy reading (see Figure 5).
Point 3- Unequivocal definitions of different types of pores must be formulated.
Reply: On the basis of careful investigation and extensive consultation with sedimentology experts, unequivocal definitions of different types of pores have been provided, and the whole of subsection 3.1 has been revised once more by AJE editors (see subsection 3.1 "Pore Structure").
Point 4- What is the meaning of Column "Representative type" in the Table 9? It is very vague.
Reply: The meaning of the column "Representative type" in Table 9 is the representativeness of the indicator (see Table 9).
Point 5- The English requires a moderate changes in some places and word usage. For example, lines 453-454, "PAPER CAN evaluate the grouting difficulty and propose...". It might seem unnecessary "So" (line 494) and "For example" (line 496).
Reply: To solve the listed language problems, lines 458-459 and 501-514 have been submitted to AJE, and a premium revision has been completed once more.
Author Response File: Author Response.pdf
Reviewer 3 Report
The paper entitled ,, A Comprehensive Classification Method for Pore Permeability 2 of Deep-mine Sandstone Used to Guide Grouting“ fullfils the character of scientific paper. The paper is scientifically valuable in terms of processing theoretical and experimental knowledge. The choice of used methodology is correct.
The paper is written and submitted according to the Author Instructions.
The paper is clearly processed. The title of the article is in line with its focus. The stated diagrams are clear and well-integrated in paper. The individual parts of this paper are listed in the correct order.
A total of 50 literary sources were used mainly from current published articles, but from older literature too. These resources are from the area of the issue and are appropriate to the content of the article.
The article is original and meets the character of a scientific article. The current state of the researche issue is suitable processed. The results correspond to the set methods and fulfill the set goal. The paper is original and well done.
In the text i tis necessary to correct several some small errors (keying mistakes), several words are connectes, e.g. in these lines 124 (ofthe), 134 (testthe), 137 (testthe), 143 (dataconcerning), 156 twosubcategories, 161 inFigures, 196 in Table, 286 and 324 (inEquation). In line 146 it is necessary to add the number of the table (Table C1?).
I recommend this paper for publication after minor revision without further review.
Author Response
Response to reviewer 3’s comments
We are very grateful to you for your valuable suggestions on revising the manuscript. Our replies are detailed below.
Point 1- In the text it is necessary to correct several some small errors (keying mistakes), several words are connectes, e.g. in these lines 124 (ofthe), 134 (testthe), 137 (testthe), 143 (dataconcerning), 156 twosubcategories, 161(inFigures), 196 (inTable), 286 and 324 (inEquation). In line 146 it is necessary to add the number of the table (Table C1?)..
Reply: All typos, including the mistakes in lines 124, 134, 137, 143, 156, 161, 196, 286 and 324, have been revised in the newly submitted manuscript, and the number of the table (Table D1) in line 123 has been added.
Point 2- There is a need in a serious revision of Subsection 3.1 (Pore structure).
Reply: On the basis of careful investigation and extensive consultation with sedimentology experts, unequivocal definitions of different types of pores have been provided, and the whole of Subsection 3.1 has been revised once more by AJE editors (see subsection 3.1 "Pore Structure").
Author Response File: Author Response.pdf
Reviewer 4 Report
1. Lines 66-68, This sentence should be omitted. It is not necessary to mention the funding project here.
2, line 69, “Materials and Methods”.
3, Move figure 1 into Supplemental materials, and this subsection “2.1” should be moved to the “Introduction” section.
4, Figures 2a and 2b should be “Figure 2” and “Figure 3”.
5, line 93, delete “.”
6, lines 91-94, what is the size of the core samples (e.g. length, diameters)?
7, line 134, It is unclear why “gas permeability” rather than “water permeability” was tested. How does “gas permeability” help people to understand water seepage? A good reason should be given.
8, lines 134-141, why not consider “computed tomography”?
9, Figures 6a,6b,6c, and 6d. The caption of this figure should be put together, see figure 5.
10. I suggest you merge figures 6c and 6d into one figure and use a different color to indicate the stone type. And why the function between porosity and permeability was not shown for Shihezi sandstone and Shanxi sandstone.
11, how other parameters may affect the permeability, microporosity and pore throats?
12. Figure 8, put figure caption together; the models used here are so complicated. It seems the authors overfitted the data. If you intend to use the complicated models, other models (e.g. linear, exponential, power) should also be tested and the best-fitted model should be selected according to the Akaike information criterion.
13. Figure 8a, what does the bar mean here “standard error” or “standard deviation”?
Author Response
Response to reviewer 4’s comments
We are very grateful to you for your valuable suggestions on revising the manuscript. Our replies are detailed below (please note the underlined text that indicates the position of the modified part in the manuscript).
Point 1- Lines 66-68, This sentence should be omitted. It is not necessary to mention the funding project here
Reply: Yes, the sentence has been deleted (see the end of the “Introduction” section).
Point 2- line 69, “Materials and Methods”.
Reply: The “Samples and Methods” has been changed to “Materials and Methods” (see line 79).
Point 3- Move figure 1 into Supplemental materials, and this subsection “2.1” should be moved to the “Introduction” section.
Reply: Figure 1 has been moved into the Supplemental materials (see Appendix A), and subsection “2.1” has been moved to the “Introduction” section (see the end of the “Introduction”).
Point 4- Figures 2a and 2b should be “Figure 2” and “Figure 3”.
Reply: Figures 2a and 2b have been changed to “Figure 1” and “Figure 2” (see the captions of Figure 1 and Figure 2).
Point 5- line 93, delete “.”.
Reply: The “.” in line 93 has been deleted (see line 93).
Point 6- lines 91-94, what is the size of the core samples (e.g. length, diameters)?
Reply: The size information of the core samples, including the length and diameter, has been supplemented (see lines 91-94).
Point 7- line 134, It is unclear why “gas permeability” rather than “water permeability” was tested. How does “gas permeability” help people to understand water seepage? A good reason should be given.
Reply: First, why “gas permeability” was tested rather than “water permeability”? Because permeability is a measure of liquid flowing through porous media, it is an inherent property of sandstone, which depends on the pore structure of sandstone and is independent of the type of liquid flowing through the porous media. The purpose of this paper is to obtain accurate classification results of sandstone permeability. The “gas permeability” test is conducted based on the relevant standards of China's oil and gas industry, the testing result of permeability is accurate, and the classification results of sandstone permeability are accurate and reliable. Additionally, samples used for the “gas permeability” test can also be used for MICP tests, casting thin section observations, scanning electron microscope observations, etc. That is, the “gas permeability” test will not damage the texture of the sample, while the “water permeability” test will damage the sample because “water permeability” test samples need to be soaked in water for 24 hours before testing.
Second, how can the “gas permeability” help us understand water seepage? Based on a large amount of “gas permeability” data, this paper can obtain an accurate classification result of sandstone, which is only the research goal of this paper and is also the first step of all the research work of the National Natural Science Foundation of China project (Grant No. 51774192). Based on the comprehensive classification of sandstone, we conducted “water permeability” tests on some samples of different types of sandstones in their subsequent studies to understand water seepage in different types of sandstone.
Point 8- lines 134-141, why not consider “computed tomography”?
Reply: There are three reasons for not considering CT: first, the area observed by CT is too small, and the observed pore structure is local; second, a scanned image by CT has a depth of field, and it is difficult to determine the pore parameters; third, the price of this approach is too high to adopt for a large number of samples. In contrast, the combination of casting thin section and scanning electron microscope observation is more suitable for the permeability classification of sandstone than CT analysis. Because casting thin section experiments can observe the pore structure in a large area, the cost of casting thin section observation is low, and we can prepare more samples and observe a large number of rock areas according to the research needs. In addition, scanning electron microscopy, such as CT, has high resolution and can identify small pore throats. In our study, considering the funding, only a small number of samples were analyzed by CT. The amount of data is too small to be statistically significant and is not suitable for use as the main data for the permeability classification of sandstone. Therefore, it is not mentioned in this article.
Point 9- Figures 6a,6b,6c, and 6d. The caption of this figure should be put together, see figure 5.
Reply: The four figure captions of Figures 6a, 6b, 6c, and 6d have been combined (see Figure 6).
Point 10- I suggest you merge figures 6c and 6d into one figure and use a different color to indicate the stone type. And why the function between porosity and permeability was not shown for Shihezi sandstone and Shanxi sandstone.
Reply: We believe that if Figures 6c and 6d are merged into one figure, the new figure will contain too much content, be too complex, and thus be unclear. The functions of the relationship between porosity and permeability are shown in Figure 6d for both the Shihezi sandstone and Shanxi sandstone.
Point 11- How other parameters may affect the permeability, microporosity and pore throats?
Reply: The purpose of this study is to improve the grouting effect in sandstone pores. Micropores in sandstone cannot be grouted at the present stage, which is not the focus of this study. The size of pore throats does have an important impact on grouting. In the comprehensive classification of sandstone permeability in this paper, the average pore throat radius obtained by the mercury intrusion test can reflect the impact of pore throats on grouting to some extent.
Point 12- Figure 8, put figure caption together; the models used here are so complicated. It seems the authors overfitted the data. If you intend to use the complicated models, other models (e.g. linear, exponential, power) should also be tested and the best-fitted model should be selected according to the Akaike information criterion.
Reply: The four figure captions of Figures 8a, 8b, 8c, and 8d have been combined (see Figure 8).
Point 13- Figure 8a, what does the bar mean here “standard error” or “standard deviation”?
Reply: The error bar in blue means “standard error” here, which reflects the fluctuation in the average value in Figure 8a (see the blue legend in Figure 8a).
Author Response File: Author Response.pdf
Round 2
Reviewer 4 Report
Dear authors,
I am satisfied with your response and the revised manuscript.
