Thank you for the opportunity to review Insights into glacial processes from micromorphology of silt-sized sediment by Lepp et al.  The paper reports a study of micromorphology of silt-sized quartz in meltwater plume deposits (MPDs) offshore of six presently and formerly glaciated catchments.  The micromorphologies of the silt-sized quartz from these deposits are compared with those in glacial tills, which are assumed to represent the parent material prior to glaciofluvial transport to form the MDPs.  The authors investigate micromorpholgies to elucidate the dominant mechanism(s) of sediment transport by glaciers.  The authors interpret their results as indicating that grain characteristics reflect mainly glacial abrasion, and that meltwater transport has made only a minor contribution to grain evolution. This information may provide a basis for inferences on glacial meltwater flow rates, distances, and pathways, which may also inform paleoglaciology and paleoclimatology.

I believe that the authors have completed an innovative study that could be of general interest to the glaciology community.  I also thought that the results were well presented in the Figures.  However, there is a large opportunity to improve the presentation of the study, including especially its key findings, through addressing important issues with the writing. At present, the key findings are not clearly and simply stated.  In particular, the Abstract, Introduction, Methods and Conclusions are afflicted by a lack of clarity.  The presentation of the Results and the Discussion is clearer.  The main issues contributing to a lack of clarity are frequent grammatical errors, long and complex sentences, being indirect in the presentation of information, and frequent gaps in logic.  It is this latter point that is probably the most critical to address in a future revision.  The Introduction could better establish the key relevant micromorphological features, including a brief overview of the relevant mechanical work that appears (too briefly) in the Discussion. What might seem clear to a glacial sedimentologist is not necessarily clear to a more general reader and, as a non-sedimentologist, I felt that there are many important gaps in logic in the present manuscript.  My general impression is that it is presently difficult for the reader to 'distinguish the forest from the trees', which is a pity because it detracts substantially from what I believe has been a good study.

I have appended a marked-up version of the manuscript with detailed comments and suggestions for improvement to the manuscript.  Many of these are minor, but I am of the view that substantial rewriting would greatly assist the presentation of this study.

Abstract

Is clear and well-written; possibly lacking in impact/significance at the end i.e. why is this research so important and how will it help future analyses of these types of deposits…and what will that mean for reconstruction purposes or for better understanding processes.

Introduction

Intro is well written and concise; again more significance/impact needed; other minor comments within the manuscript itself.

Materials and methods

Not sure why till and ice-proximal diamicton deposits are considered to be the same in terms of sediment transport processes and thus grain textures; sec 2.1 needs references; see other comments within the manuscript itself.

Results

The main issue with the description of the results is that it is unclear what deposits the grains have come from for each of the different site locations – MPD or till? Just please remind the reader throughout. Also, there is no real mention of the results of grains from ice-proximal diamictons – presumably because (according to an earlier sentence in the methods section) the till and ice-proximal diamicton results have been merged together?? But it remains unclear why this is, why not just keep them separate, since they are entirely different kinds of deposits? There seems to be some inclusion of interpretations (the bit about how the local geology may reflect some of the grain results) when this info is probably better off in the discussion?  

Discussion

In general, there is a lack of reference to the actual sites/results from this study – would like to see the results and sites more systematically dealt with within each sub-section of the discussion. Many sentences in the discussion are not worded very well, the writing style could be tightened up significantly.

4.1– Geological differences at each site are not explained anywhere – what is the local geology for each site? this section is really difficult to follow since there is a lot of information that the reader is assumed to know (but doesn’t know); see comments within the Ms itself on where and how to make sentences clearer

4.2 – this reads much better than section 4.1; it tells the reader what has been seen (from these results) and what they mean (whereras 4.1 fails to do that)

4.3 – is fine, see comments within.

4.4 – needs clarification in place, see comments within.

Conclusions

Might be better off as bullet points? See comments within.