Accessing the Time-Series Two-Dimensional Displacements around a Reservoir Using Multi-Orbit SAR Datasets: A Case Study of Xiluodu Hydropower Station
Round 1
Reviewer 1 Report
Xiluodu Power Station, the second-largest water conservancy project in China, is of great economic significance. In this paper, 2D deformation information near the Xiluodu reservoir area was obtained by ALOS2 and Sentinel-1 with a long-time span from 2014 to 2019. And then, the relationship between water level and deformation was deeply analyzed, which has important reference value for disaster prevention and control of the power station. Overall, this is a good InSAR application article. However, the article still has the following problems to be modified:
1. Errors in text
Line 60: geohzard -> geohazard
Line 185: dlos ->
Line 274: “In the phase unwrapping, we select the unwrapped reference point at the same position away from a stable area in the county.” is ambiguous.
2. Specify the full form of any professional acronym when it appears for the first time
Line176: MinA
Line 246: SRTM.
3. Figure 4: The establishment of the coordinate system and notations in the diagram should be explained in more detail.
3. Section 3.1: Describe the stochastic model briefly
4. Figure 6. (b): The figure is fuzzy. The meanings of boxes in different colors shall be indicated.
5. Figure 7: Annotate the meaning of nodes and connection lines
Author Response
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Reviewer 2 Report
The authors used ALOS2 and Sentinel-1 time-series data to analyze the displacement ranging from 2014 to 2019 over Xiluodu hydropower statio. This paper is solid and structure is reasonable. I think this paper can be published after some minor revision. My comments are given as follows.
1. please cite the studies that have used InSAR techniques to investigate Xiluodu Station.
2. Some typos should be carefully modifed (e.g., heading "statio").
3. Tikhonov regularization solution is deployed, please clarify why R in (9) will be used ? Moreover, how do you handle the case where the determination of alpha using L-curve fails .
Author Response
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Reviewer 3 Report
Dear Authors,
An important study focused with Dam having a water level of about 600m. The introduction of a section on "Data" before the section on "Method" will be good. Add a clear flowchart on Methodology.
43. sub section on Results / Section 5 on results. Rewrite /reframe the section on Method; Results and Discussion.
best wishes,
Author Response
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Reviewer 4 Report
This manuscript provides an accurate analysis of satellite observations of ground displacements near a hydroelectric plant, located in SW China. Five years of InSAR data have been investigated, with a resulting detailed investigation of the deformation field evolution and the related source mechanisms. The geological setting is clearly illustrated. The methods of data analysis and the processing techniques are clearly presented. The precision analysis is very robust, allowing to constrain the limits of the two-dimensional deformation field. The relationship between the deformation and the water storage are well presented. I have appreciated the critical discussion of results and the discussion on the potential geological hazards. The paper is of high quality, and it is generally clearly written and illustrated.
The conclusions are consistent with the data analysis and the references are appropriate. I recommend this paper for publication in Remote Sensing.
Minor notes:
Line 4: Statio-> Station
Line 60: geohzard-> geohazard
Author Response
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Author Response File: Author Response.pdf
