The Largest Geodetic Coseismic Assessment of the 2020 M_w = 6.4 Petrinja Earthquake

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors of the manuscript “The largest geodetic post-seismic assessment of the 2020 Mw =  6.4 Petrinja earthquake ” present the geodetic estimate of the co-seismic displacement to due to the 2020 seismic event in Croatia, using the InSAR and GNSS techniques. 

 

My first concern is related to the title of the manuscript. The authors use the term “post-seismic” instead of “co-seismic”, which is what they have actually estimated in this work. 

 

In Figure 1 the red arrows represent the ground displacements between the two largest earthquakes in 1880 and 2020, but information on how this estimate was obtained is lacking. The black arrows represent velocities during the period 1994-2013 as reported in reference [47], but the cited work is a PhD thesis in Croatian. Are there any more recent publications that also use data collected after 2013? The error ellipses are not reported in the plot.

 

The authors affirm that the GNSS measurements have been performed on “289 permanent geodetic stations of the GNSS and trigonometric networks of lower order”. Concerning the GNSS stations could specify how many continuous GNSS stations  (cGNSS) you have used? Did you use only stations like the ones of picture 9? 

 

If I understand correctly, the GNSS co-seismic displacements have been computed comparing the GNSS coordinates with the values obtained from measurements taken from January to April 2021 and during October and November 2021. To which epoch do the coordinates before the earthquake refer? Is it 2008.83, as reported in line 299? 2008 seems too far from the Earthquake event. 

 

Please check the numeration of the figures, because at line 370 there is Fig. 2 instead of Fig. 11, and so on. 

 

Minor remarks:

Line 18: “horizontal displacements” —> “horizontal coseismic displacements”

Some reference are in Croatian.

Table 1: please reformat the table to simply the reading. 

Author Response

Dear Reviewer,

Please find the detailed responses in the attached file and the corresponding corrections highlighted in blue in the re-submitted article file.

With kind regards,

Authors

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The article addresses the seismic activity in the city of Petrinja, which was affected by a series of significant earthquakes in late December 2020. The study focuses on determining the displacements of the Earth's crust caused by these earthquakes using GNSS measurements and InSAR techniques, comparing the results to understand the geodynamic movements in the Dinarides area.

• The article does not provide sufficient background information on the geological context of the Petrinja region and the significance of the Pokupski and Petrinjski faults. This background is crucial for readers to fully understand the reasons behind the increased seismic activity.
•  While the article mentions the use of GNSS and InSAR techniques, it lacks a detailed explanation of how these methods were implemented, including the specific equipment used, the data processing steps, and the accuracy of the measurements.
• The comparison between GNSS and InSAR results is mentioned but not elabor
  
  
  There are some related articles where the authors can use benefits of them in their article:
  -Field Reconnaissance and Earthquake Vulnerability of the RC Buildings in Adıyaman during 2023 Türkiye Earthquakes
• 
  

  -The 2020 M_w 6.4 Petrinja earthquake: a dextral event with large coseismic slip highlights a complex fault system in northwestern Croatia

Comments on the Quality of English Language

It needs only minor correction and control it again for typo mistakes.

Author Response

Dear Reviewer,

Please find the detailed responses in the attached file and the corresponding corrections highlighted in green in the re-submitted article file.

With kind regards,

Authors

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors, 

thanks a lot for the exhaustive explanations and for taking my suggestions into account.