The manuscript presents very relevant and timely contributions to the field of HWC modelling.
Minor comments:
Abstract: Typically an abstract does not contain paragraphs. please confirm with the journal's style guide.
The first paragraph of the abstract reads more like an introduction. An abstract is supposed to be concise.
In section 2.2 you should clarify the source location or how you get to retrieve the different incidence angles in Figures 4ff. Your workflow is not clearly described and thus not reproduceable. This is currently the major flaw of this manuscript. What is your input amplitude of the wave? The model dimensions are missing, as well as a description how values were extracted from the model to obtain the figures. It is good scientific practice to explicitly write the steps required to reproduce your work. A homogeneous (cement) block would be great as baseline model
Your models and figures only show HWCs never straight cable. in the data examples in the end you then make conclusions about comparison. I may have missed some arguments here?
Line 22: Two dots before "Results"
Line 22: "modified" -> you never mentioned the unmodified model, so this seems out of place...
Line 56: DAS can very well detect (dynamic) strain from hydro-fracs in vertical wells. It all depends on relative geometry and incidence angle.
Line 79: arkward grammar with 5 verbs in succession.
Line 96: be consistent in upper or lower case writing of "Appendix" (see line 102)
Line 114: Dot missing after "processing"
Line 130ff: This feels like a repetion from earlier. Maybe track-changes left-over fragment?
Table 1: Scenario 5: What does "they are cable" mean????
Table 2: your eta is physically identical to the wavelength, which is in seismology typically denoted with lambda.
Why did you chose 1/12 of the wave length?
Why are some paramters given in absolute diameters, others relative to wave length?
Which (dominant) frequency is assumed?
Line 153: Dot missing at the end of sentence
Figure 3: You never mention the (absolute) dimensions of you model
Line 170: Change to "Figure 4 and 5"
Line 172: What units are the RMS errors (I suppose in "strains", typically denoted by epsilon)? Or is it in percent?
Figure 4: please clarify your angle definition. I suppose 90deg is cable parallel?
is your "fibre strain" the ezz of Kuvshinov, or the strain in the surrounding material
Figure 5: Here are smaller max values than in Figure 4. Comment on this
It may be instructive to have a simple model of a cable in a homogenous cement block as a baseline model....
Line 203: Fig 6 and 7 "compare" it is difficult to compare if the two have different color scales...
Line 207: Repeat WHY they cannot be compared
Line 218: Check figure numbering, Fig 13 seems wrong here
Line 223 "lesser" -> "smaller"
Line 240f: The sentences starting with Scenario #5 /#6 can surely be simplified by mentioneing similarities and differences
Fig 6-11: If I undertand your paper correct you are modelling a plane wave traveling trough your model. Here, you show a static strain "snap shot" of the wave? at what time step? How does that strain translate into DAS amplitudes? How are these figures related to fig 4&5?
Line 241: This first paragraph of the discussion is in fact part of an introduction. I am sure the experience of the co-authors will help here to reformulate and restructure.
CONCLUSION:
Explicitly write about benefits of HWC. At the moment it sounds very sceptical, but there seems to be features in the data that can only be explained when using HWCs. |