reviewer one

"Characterizing Hillslope Response to Regional Erosive Events as Preserved

in Alluvial Fan Deposits in Western New England" a thesis proposal by

Karen Jennings.

This proposal is about the use of humid region alluvial fans as records of

increased erosional rates of adjacent hillslopes. Jennings explains the

methodology of using alluvial fans to reveal past perturbations of the

landscape.

This proposal is in a reasonable state of progression toward a finished

product. Avoiding the passive voice will make the document easier to

read. Better focus in the previous work section will make the document

more concise. More focus on what the main issue is (human or storm vs.

climate) will make the document easier to understand. Focusing on either

issue is fine, but the document should read in that way rather than flip

flopping back and forth.

Once this proposal has a few more revisions I think it will be a fine

document that addresses some very interesting science, with possible

interesting results.

1) If you include NY you cannot use New England.

2) title page

3) For the whole abstract you discuss storms and climate change and then

at the end you through in humans. If this is going to be a focus of your

research then you should mention it earlier. Right now it seems like an

afterthought.

4) Hmmmaybe it is just me but this sentence makes your thesis sound like

you are population and destruction driven. Are you?

5) Is it the best way or is it a way? Computer modelers would have a fit

over this statement.

6) Not all alluvial fans are an excellent tool, some yes. How about

saying some alluvial fans are one tool

7) From the fans only, you get deposition histories. From the basins you

can get erosion histories. If you are in a heavily populated area the

basins very well may have been modified, or the fans for that matter (like

mining for gravel)

8) Again this sounds like you are searching for the bad human element.

The whole climate or storm part is natural.

9) What do you mean by scale, spatial or temporal?

10) Intensity and/or duration? or just amount?

11) Slash and burn does not cause fan deposition, increased rainfall

intensity or duration does. Slash and burn makes the sediment easier to

erode.

12) What does this have to do with your stuff? How does recurrence

intervals relate to climate change or human altering the landscape?

13) Seems as though you are more summarizing what Kochel did instead of

telling us why his work is important for your study that deals with

storms, climate and/or humans. You need tell us why it is important.

14) You sound pretty sure about this. Why do you use two hillslopes

rather than one? What if the hillslope has no sediment then there will

not be increased deposition. What if the storm does not exceed

infiltration capacity? Then you probably will not get sediment transport?

15) Which fans you were just talking about hillslopes last sentence?

16) Does research seek or do humans seek?

17) Can you use New England? Or do you have to use VT and NY.

18) I am starting to wonder how important the human thing is here. Yeah I

know that is a cool part but Amy and Paul have already documented in two

theses that humans are indeed a major forcer of sed. deposition on

alluvial fans. I would try and concentrate on the storm or climate change

part and address the human thing as a secondary but still important part

of the puzzle.

19) Wow I read one sentence farther and I see what I just said above. So

since you hypothesis. I bet we see the human aggravated deposition almost

everywhere the cool part is, if we see correlative events lower in the

profiles.

20) What do you mean by condition?

21) Several means three or more

22) That is only if all fans start then. I bet some fans start at a

latter date.

23) How thick?

24) Does this mean that you are going to the bottom of each fan and you

are going to get a basal age?

25) What GPS?

26) I have seen fans on topos that are not miles in width.

27) How do we know how long it has been since the river was around?

28) Which areas?

29) How can cars investigate?

30) How will you know this?

31) Did you get on your hands and knees? What did you do?

32) Can you just say you will calculate the volume of the basin area that

feeds the alluvial fan to compare to the alluvial fan volume?

33) Is this valid? Do you think different parts of fans have different

depositional rates? Think of the Aldrich fans this summer. Lost of stuff

at the apex and it thinned as we went to the toe. How can you account for

this?

34) This is the first time you mention anything about continual slope

stability and sediment yield. This should come before the last sentence.

REVIEWER 2

Critique of Jennings, K. L., 1999, Characterizing hillslope response to

regional erosive events as preserved in alluvial fan deposits in western

New England. University of Vermont Masters Thesis Proposal, 16 p.

Anders Noren

3/1/99

The author presents her project proposal for her Masters thesis

research. She plans to examine via backhoe trench the sediment

stratigraphy in several small, postglacial alluvial fans throughout

Vermont and eastern New York. She will make visual logs of this

stratigraphy, use radiocarbon methods to date the timing of layer

deposition, and calculate fan aggradation rates. She will use these

rconstructed depositional histories to determine the erosional histories

of hillslopes above the fans, and by inference, the history of large storm

events across her field area. She will determine whether hillslope

erosion, and consequently storm events, are temporally and spatially

correlative in western New England.

The proposed research some revisions are needed. These include

eliminating redundancies, changing from passive voice to active voice as

much as possible, and rewording a few confusing passages to clarify the

writing. A few structural changes will further clarify the paper. If

additional references exist on the subject, the author should use them;

otherwise, she should explain more clearly that they do not exist (cite

individual references from Kochel; also, might arid fan studies be cited

as examples for this studyfor methodology at least?). The reference style

needs minor changes. Also, does the paper length exceed the guidelines of

the Geology Department?

These comments aside, the proposal has plenty of merit. I

recommend this proposal for acceptance by the faculty with the changes

noted below (referenced by number to their location in the manuscript) and

on the manuscript itself.

Comments:

1. Seems to me that drainage basins have erosionalnot

depositionalhistories, for the sediment erodes from the basin and deposits

on the fan. So the fan itself (and other places where sediment comes to

rest, like lakes) would have depositional histories.

2. Maybe you ought to mention anthropogenic disturbances before this last

sentence of the abstract.

3. Is there another word besides "nature" that you could use? It sounds

fluffy.

4. Reword: "hillslope erosion resulting from both natural phenomena such

as large storms or forest fires, and human-induced change such as

clearcutting."

5. These two sentences are redundant. Your argument is strengthened

without them.

6. Reword: "Human activity such as hillslope deforestation" (slash and

burn sounds a bit extreme, like youre trying to evoke emotion in the

reader)

7. Are there other refs you could use in this paragraph besides Kochel

(1990)? Maybe Church or Zehfuss? If not, just site Kochel once and then

talk about all the things he/she determined.

8. This sentence is confusing. Storms produce sediment yield; do you mean

that in those fans sediment from individual storm events was observed?

9. Reword: "Kochel (1990) [determined/predicted] that [substantial

hillslope erosion/debris flow generation] in mature forests would require

storms similar in size to tropical hurricanes with recurrence intervals of

3000-6000 years."

10. Can you summarize these data in a table (and maybe a figure)?

11. Some of the info can probably go in a table (see comment #10).

12. Again, hillslopes respond with increased erosion, not aggradation. The

fans at the bottom of the slopes aggrade as a result of the hillslope

response.

13. I was slammed for saying the my research seeked to do something (maybe

you too?). You are the one doing the seeking. Research doesnt seek. People

seek.

14. You can move this entire paragraph (and the last sentence of the first

paragraph in this section) to your methods section. The other paragraphs

are strong enough alone for this section.

15. Reword: "I will examine fans from different river valleys across

Vermont and New York".

16. Reword: "As a result, I needed to determine where small alluvial fans

are created and preserved."

17. Do you need to include this information? Maybe you do; it seems a bit

basic to me. Check with Paul.

18. Rewrite this paragraph to state these as tools you will use to examine

the fans. Dont spend words or space explaining how you acquired the

skills; simply state that you will (for example) use a Trimble 4400

Real-Time Kinematic GPS and Pentax Total Station equipment to survey the

fans and their gullies; that you will use grid methods to log fan trench

walls; and soil colors and textures to determine the relative ages and

exposure histories of layers within the fans.

19. A ref would help here. Others have used this method/equation, right?

Karen Jennings proposes to study a set of alluvial fans in different valleys across Vermont and New York. By trenching alluvial fans, Karen hopes to identify paleo-soil horizons that can be dated to pre-settlement, in order to show how deforestation increases erosion rates on hillslopes. Karen will use gravelly deposits and large sediment layers lacking soil horizons in the fans to identify large storm events that triggered increased erosion on hillslopes. Karen hopes to correlate specific layers in the alluvial fans to find if hillslope erosion is regionally synchronous.

Karen's proposal clearly and succinctly covers all the necessary parts of a proposal. The abstract is short and descriptive and the last two sentences spell out what she will research and what the conclusions will used for. The remaining sections are complete and I especially liked the expected outcomes section. Providing a set of expected outcomes shows that you have a good idea what your going to find and that you are already thinking about your research. Figures complement the proposal and do a good job of summarizing previous work of others. One question that I think needs to be answered before this proposal is finished is will you definitely be able to use sediment accumulation rates to infer the frequency of large storms in New England? In other words: Will the carbon dating allow you to distinguish between large regional storms (like a tropical storm) that triggered erosion and subsequently deposition on fans in the same year and smaller, but equally intense storms that may have triggered deposition on all of the alluvial fans during different events in different years? Beyond this question, which can probably be answered with a short paragraph, and a few specific comments this proposal should have no problem being accepted by the faculty.

Specific Comments:

1) I would add "and Deforestation" after the words Regional Erosive Events. The sediment layers corresponding to deforestation seem to be a large part of both you research and the previous work.

2) Maybe word this as 'reduces soil cohesion' instead.

3) Will you really be able tell magnitude of the storm not in terms of rainfall intensity/duration, but I guess you can tell magnitude by recurrence interval.

4) This sentence is a little confusing to me, how do the eroded stream banks fit in?

5) You might add the percentage of time since the fan's birth that it took for the sediment due to deforestation to be deposited we did it for Geomorphology last year, it is a staggering number, something like 25% of the fans volume deposited in <5% of the fan's existence. (Not a big deal, but its an interesting value)

6) See question I pose above in second paragraph.

7) The figure 5 caption does not really flow with the text.

8) What happens when gravel is not present in the source material, how will you be able to still identify large storms?

9) Have you identified any fans that you will definitely use yet, if so tell us where and why (include map).

10) and/or the importance of smaller scale intense storms (see (6) and question in paragraph 2).