Review Reports - Off-Line Stacking for Multichannel GPR Processing in Clay-Rich Archaeological Sites: The Case Study of Tindari (Sicily)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study proposed and validated an "off-line stacking" data processing method for multichannel GPR systems, which successfully enhanced signal-to-noise ratio and image clarity at the clay-rich Tindari archaeological site, significantly outperforming traditional methods and providing a more effective tool for archaeological surveys in challenging geological conditions. However, there are still some issues that should be addressed appropriately. I hereby list the most relevant points as follows.

1.The main issue in this paper is the lack of quantitative metrics. The study claims improvements in "clarity," "signal-to-noise ratio," and "quality" but provides no objective, quantitative measures, such as SNR calculation in dB. It is recommended that the author supplement this section accordingly.

2．Additionally, the author may need to address the issue of potential resolution loss. Off-line stacking inherently involves averaging signals from slightly different spatial positions. While suppressing noise, this averaging can smear small, discrete targets or reduce lateral resolution, especially if the group size or channel spacing is large relative to target size. This trade-off (SNR gain vs. resolution loss) is not discussed or quantified.

3．The comparison is only made against "conventional in-line stacking." It does not compare the proposed off-line stacking against other advanced processing techniques commonly used in challenging environments (e.g., more sophisticated filtering, F-K migration, Radon transforms, wavelet denoising, multi-component analysis). Is off-line stacking genuinely superior, or just better than the simplest alternative?

Author Response

Dear reviewer, please see the attached document with our replies to your comments. thanks!

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Off-line stacking for multichannel GPR processing has been proposed to improve the signal-to-noise ratio. For me, this is a very interesting study. Before this manuscript is accepted, there are still some issues that need to be addressed.

A schematic diagram of the principle of a new method needs to be added to facilitate readers' understanding. The detailed processing procedure should be explained.

The case studies provided by the author do not have particularly significant effects. I suggest adding new experiments, such as more specific underground targets, to see the effectiveness of the new and traditional methods.

Author Response

Dear reviewer, please see the attached document with our replies to your comments. thanks!

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Review report on Manuscript ID: applsci-3680684[Off-line stacking for multichannel GPR processing in clay-rich 2 archaeological sites: the case study of Tindari (Sicily).]

Brief Summary:

A non-conventional processing technique- off-line stacking method was tested in the study reported in the manuscript with a view to improving the interpretation of GPR multichannel data acquired over an archeological test site. The technique was compared with the traditional in-line stacking, and results were found to have enhanced the signal-to-noise ratio and thus, aided better clarity of 2D and depth slices of the recorded signals for good interpretations. It was concluded that such an approach could be used in a highly lossy environment, such as clay-rich soil.

General concept comments:

Well articulated concept and presented in a good scientific format.

All the sections are well presented.

There is excessive self-citation (Cesare Comina, the first author, was cited 4 times, and Andrea Vergnano was cited twice ). This should be properly addressed.

Citations in the manuscript are quite recent references- 12/27 are publications within the last five years (2020-2025), representing approximately 44%.

The research is scientifically okay considering the concept.

The concluding part of the manuscript is relatively okay, but could also be improved.

Specific comments:

Abstract:

Well-written and comprehensive enough.

Introduction:

Well-presented Introduction section showcasing the gap that the study aimed to address.

Methodology:

There seems to be an omission in the statement on Line 190. Authors should check the statement again.

Generally, the section was chronologically presented, making the method of study well-comprehensive

Results and Discussion:

The only concern in this section is the resolution of the figures presented. I hope they are better in the supplementary document that accompanied the manuscript.

Statement lines 279 -280 could be substantiated specifically with figures.

Conclusion:

The conclusion is well presented.

Comment on the Quality of English Language:

I am a native English speaker, and I was able to comprehend every section of the manuscript. Only minor corrections are needed in some parts of the manuscript. Authors should check long statements, making them more concise.

Author Response

Dear reviewer, please see the attached document with our replies to your comments. thanks!!