This is a very nice microstructural study on the Zechstein salt sequence rocksalt samples that address the rheology of subsurface salt formations. The manuscript is concisely written, reads well, English is good and the imagery and diagrams are also well prepared. The microstructures of selected samples are also nicely illustrated in traced grain boundaries (Fig. 3). The outcomes are relevant for salt tectonics researchers and salt mine engineers.

I only have some minor comments and suggestions on how to improve the manuscript. These suggestions are provided as embedded „sticky notes“ within the annotated pdf that I attach to this review.

I would point out the two main remarks that should be addressed by the authors in the revised version.

• The rheology contrast between the coarse rectangular halite grains in the ‘Kristalllage/Kristallbrocken’ and the fine-grained ‘matrix halite’ is attributed to the different deformation mechanisms. I quite agree with this, but the reason for this difference is mainly the original grain size, explained on line 314. All other features are secondary. The Bromide impurity content discussion is redundant as no Br content data from this study or earlier studies is indicated. Can you offer the explanation for these enigmatic Kristalllage layers in the introduction, and how the large crystals of halite may have formed? Does it reflect a special sedimentary/diagenetic environment? Can we expect such very coarse-grained in other salt basins?
• The discussion does not completely reflect the datasets acquired in the manuscript. The quantitative datasets - grain sizes presented in Figure 7 are completely omitted in the description (Results section), although this is the only link between the salt samples from the 4 diapirs studied. Can you evaluate the meaning of the grain size distributions from the diapirs a bit more? Do you find any correlation in grain size, the degree of macroscopic deformation (e.g. intensity of folding, boudinage at sampling site), and the modal content of Kristallbrocken layers vs. matrix rocksalt between the studied diapirs? Do the samples show any difference? Instead, the discussion about the composite rheology of the mechanically anisotropic rock sequences containing the coarse-grained layers is inaccurate and not supported by the datasets.

I suggest dividing the Results and Discussion sections into subsections. For the results section, you can provide first the microstructural description (shapes of crystals, the relationship between layers, modal content of Kristalllagen/Kristallbrocken), second the quantitative microstructural analysis (grain sizes, subgrain sizes), and third the EBSD data.

Reference to figure 7 is completely missing!!! Dataset presented in Fig. 7 is not described or discussed, although this is one of the primary results of this whole quantitative microstructural study.

Keep the sequential referencing of the figures throughout the text. For example, Figure 8 is called before Figure 6 in the text.

Revise the micrographs, few of them would be more distinct when their contrast and brightness are enhanced (Fig. 5b, f, g, also 4b).

This is well written paper with a thorough, detailed, and very welcome description of salt microstructures. The main message, the role of grain size, comes across well. I have added comments and suggestions directly in the attached document.

There is one general point that requires clarification, to my opinion.

On the one hand, it is indicated that the matrix is dynamically recrystallized (e.g. lines 35, 129, 396), what I interpret as driven by differences in strain energy related to dislocations (there are subgrains in the matrix), on the other hand, the fraction of rex grains is interpreted to be low (line 359) and the fine grains are thought to have been present already before deformation (line 323). So the conclusion is that the matrix deformed by grain size dependent pressure solution creep, and not by disloc mechanisms. I propose that the authors are more clear on the observations regarding rex in the matrix and better underpin their interpretation that the small grain size in the matrix is pre-deformation.

Related to this point: data on the grain size of the matrix are presented in Fig. 7, but these data seem hardly been used (and there is no reference to the Figure in the text). Importantly, if one would assume that the matrix grains are recrystallized grains, and then apply the rex grain size piezometer from Ter Heege et al. (2005), one would get unrealistically high stresses. This supports the interpretation of the paper that the matrix did not deform by dislocation creep.