Evaluation of the Possibilities Validation of Interval Velocity Models Using Non-Seismic Data and Its Impact on Geological Interpretation of PreSDM Results

Round 1

Reviewer 1 Report

The authors present a generation and validation method for velocity interval per depth (VID) models with the application of non-seismic geophysical and geological data. Overall, this paper is well-written. I have some major comments as follows:

(1) Because refraction and gravity data are important to construct the velocity model, can you show those data in the paper?

(2) The selected D-4 and R-8 wells are located in areas where the structures are not very complex (Figure 10). Could you verify the feasibility of the proposed method in areas with complex environments?

(3) Figures 9 and 12 are Kirchhoff Prestack Depth Migration (PreSDM) results. For complex structures, the Kirchhoff method may not provide accurate images. Could you improve the image quality using more accurate imaging methods, like reverse-time migration?

(4) If the authors overlap the predicted interval velocity over the PreSDM image, it will be more intuitive to evaluate the results.

Author Response

Author Response File: Author Response.docx

Reviewer 2 Report

In this paper, the authors construct VID models using non-seismic geophysical and geological data by Simultaneous Joint Inversion method. This is an application paper, and the methods used in the paper have been proposed in previous papers. This study conducts joint inversion using refraction seismic data and gravity data for velocity modeling, and verify the correctness of VID model evaluation and its influence on the quality of seismic imaging in the area of the Carpathian Overthrust. However, I have the following concerns about this paper:

1.The structure of this paper is not clear enough and needs to be reorganized. For example, in the third section, there are many reviews about the joint geophysical inversion researches, which should be placed in the Introduction part. In section 3, you can only introduce the methods used in the paper. Subtitles can be added to each part to make the structures clearer.

2.The rock physical relationship of velocity and density is an important point of the joint inversion in this paper. What kind of relationship does this paper adopt? Can it reflect the real situation of the study area?

3.For multi-parameter inversion using seismic data, the current cutting-edge methods, such as the full waveform inversion method, can invert velocity and density at the same time, which is more reliable than the parameter inversion dependent on the rock physical relationship. Compared with this method, what are the advantages of your method?

4.I suggest providing the whole workflow of the method or algorithm, which can help readers to better understand your method.

5.In Page 13, there are variables in the formula without explaining the meaning.

no

Author Response

• The clearity of the some sentence was corrected.
• The entire text was checked by authors. 
• Line 82-83 were corrected.
• Line 124 - 125 were corrected.
• Line 82-83 were corrected.

Author Response File: Author Response.docx

Reviewer 3 Report

The authors present an interesting study on the construction and validation of VID models, based on a novel method of integrated inversion of independent geophysical data. The paper is well written and structured. I recommend this paper for publication, after a minor revision in compliance with the following.

COMMENTS:

1. English should be edited more carefully, as some of the sentences are not clear. For example, in Line 82, is the word „deliberated“ the right one?

2. Moreover, in the same Line 82, there should be full stop and new sentence starting with “Also, the research…”

3. Line 120, what is the meaning of “which reservoir the Rączyna play”? Did the authors mean to say “which reservoir the Rączyna gas deposits”?

4. Figure 1 shows the location of the analyzed seismic profiles as well as locations of the main drilling wells but there are no vertical profiles shown. The authors mention that the “geological spatial data, used for map construction, were freely pro-125 vided in the SHP format by the State Geological Institute-PIB.” Do these data include at least some vertical profiles? Is it possible to present (in this or a separate figure), at least some approximate vertical profile showing a spatial variation of the depth of the deposits in the analyzed area?

5. Line 426: The last part of the equation (fi-coupling) should have uppercase fi letter.

English should be edited more carefully, as some of the sentences are not clear. For example, in Line 82, is the word „deliberated“ the right one? Moreover, in the same Line 82, there should be full stop and new sentence starting with “Also, the research…”

Author Response

Thank you very much for all the comments. We have tried to take into account all comments in the revised text. We would like to emphasize that the text will be verified by a native speaker before publication.

Deatiled descriptions about Kirchhoff PreSDM  was added to sec.3 sections.

Figure 5 is a compilation of diagrams presented in the referenced publications. The use of this methodology in Polish conditions, which has not been used so far, should be treated as a novelty here, as well as an indication that using non-standard procedures for validating velocity fields can improve the seismic record.

Line 632 - the sentence has been corrected.

Author Response File: Author Response.docx

Reviewer 4 Report

In this paper, the authors have addressed the validation of VID models.
Here are listed my remarks:
1) I suggest adding at the end of the Introduction some sentences like "In sec. 2 we will describe the area.. in sec. 3 the methodology will be discussed etc.."
2) Sec. 3 is not clear, in order to increase the readability of the paper, I suggest describing f.i. the Kirchhoff PreSDM instead of anticipating and discussing part of the results obtained. Please add a clear description of what you have done and the tool used.
3) Caption of Fig. 5 "based on published instructions", what does it mean? please add an explanation of the novelty you have introduced in the current paper.
4) l.632 "The article presents the use of parametric modeling..", it is not clear, please rephrase it with the help of a native speaker.

The readability of the paper should be improved with the help of a native speaker.

Author Response

Thank you very much for all the comments. We have tried to take into account all comments in the revised text. We would like to emphasize that the text will be verified by a native speaker before publication.

The extra subsections have been added.

Text was corrected and claryfied. Acronyms LVL and MVA were defined in the text (Sec. 3). 

Author Response File: Author Response.docx

Reviewer 5 Report

This article proposes the generation and validation of velocity interval per depth models from non-seismic geophysical and geological data, applied to a complex region such as the Carpathian Foredeep. As any inversion model, the validation of the model proposed relies on a priori knowledge of the modeled region.

The approach proposed employs many references and information. However, it was difficult for this reviewer to follow the text, specially the section 3. Methods and Materials. The details provided appear to be relevant and important, but the redaction of the section is not clear. It is suggested that the authors organize this section in subsections. The flow diagram provided (Figure 5) might contribute to clarify the described process, however this flow diagram should be improved as the "flow" is not evident for this reviewer (for instance, in the node connecting  "CG calculation" and "Joint objective functions"). I understand that the data related to such projects is restricted. As suggestion, it might help to provide proposed examples of the many detailed processes, specially in section 3, as complementary data. Although the references are provided, it should be helpful to provide specific details about the weighting employed for the combination of different information employed for the estimation of the final model. The section "Research results and Discussion" should be organized in corresponding subsections defined in the previous sections. This suggestion intends to clarify the content. The section "Summary and conclusions" should focus more on the advantages of the methodology proposed than on the general limitations of the inversion procedures. As produced, the contributions of the methodology are obscured by the limitations of the inversion processes. 

The text should be revised by an english native speaker to correct some minor mistakes. Also please define acronyms when first mentioned in the text, such as LVL and MVA. Although known terms, it might help to the readers. There are some orthographical mistakes, such as, in the reference of the figure 4, between lines 333 and 335; also summary in line 621.

Author Response

Thank you very much for all the comments. We have tried to take into account all comments in the revised text. We would like to emphasize that the text will be verified by a native speaker before publication.

Text was corrected and claryfied. Acronyms LVL and MVA were defined in the text (Sec. 3)

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The reviewer believes that many modifications have been made in this new version of the manuscript. All revised contents such as workflow chart have been accomplished in detail in the new manuscript according to the review comments and suggestions. The authors have answered all of my questions. That is, the paper has been much improved after this revision.  I recommend the paper be published as it is.

Author Response

Thank you very much for all your comments. We have tried to include all comments in the corrected document.