This is the story of the deglacial history of Vermont, specifically the identification, mapping, and correlation of ice margins across the entire State, including correlations with neighboring Quebec, New York, and New Hampshire. This has never been done before. A long time ago, from 1966 to 1980, I was on the faculty at the University of Vermont, initially involved with teaching and research on Vermont Pleistocene glacial geology. My research back then involved mapping from the Quebec border to Middlebury in the Champlain Valley and from Lake Champlain on the west into the Green Mountains on the east, generating substantial glacial history information. I published a report in 1972 about proglacial water bodies in the Champlain Basin but I was unable to decipher the deglacial history of this region.
Whereas substantial research by others subsequently has been done since then, this has focused primarily on detailed mapping with inferred ice margin positions based on proglacial lake history but has not specifically identified and mapped ice margin positions per se. Thus, the deglacial history of Vermont has not been established, representing a gap in the record. In time, my interests turned to applied environmental geology and hydrogeology, whereby I eventually left academia. But unrequited curiosity can be a plaguing thing and a huge motivator. So now, late in life, I am once again revisiting this history.
Two years ago on a bike ride in the Missisquoi Valley I came across glacial features that I had seen in the late 1960s, reminding me of intriguing evidence indicating that the ice sheet was still present in the final days of the Champlain Sea, actually readvancing and perhaps closing the basin once again to reestablish a higher proglacial water body in the Champlain Basin. In my 1972 report I recognized but did not fully understand such complexities, leading me to include a section on “speculation,” aimed at pointing to the need for further study.
Over the years I have kept up with the literature and realized that the Missisquoi features unfortunately have been forgotten. This prompted me to write an open letter to the Vermont State geologist as a reminder about these features and the prospect for significant information about deglacial history in this area. On a whim, I then decided to examine online information provided by the Vermont Center for Geographic Information (VCGI) for the Missisquoi and Memphremagog areas. This was intended to be brief and just for fun.
Of course, VCGI and its information did not exist in the 1970s. Back then, mapping was done the old fashioned way with a USGS map and a shovel; in the Missisquoi area the best map available was a 1”: 62,500” scale USGS topographic quadrangle map with 20 foot contours, which is extremely limited. Today, advances in digital technologies have dramatically changed the process of mapping. VCGI’s digital maps are “zoomable” to a scale up to about 1:3,600, nearly 20 times better than the 1:62,500 maps, with 10 foot contours. VCGI also makes a variety of other types of information available online, such as Stewart and MacClintock’s statewide glacial map (these authors did not identify and map deglacial history showing changing positions of ice sheet margins, but their map and associated report contains a wealth of useful information). VCGI likewise presents other helpful information such as Vermont Highway Department soil boring aggregate maps, and the Soil Conservation Service soil type and onsite septic waste disposal favorability soil maps. VCGI also provides LiDAR imagery, which of course as is now well known for glacial geology is a dramatic technology enabling the identification of features on the landscape never before been seen. From the standpoint of my studies of glacial geology in the old days all of this is a huge improvement.
As stated in this present report below, my chance bike ride encounter in the Missisquoi and my following examination of VCGI and LiDAR imagery proved to be a “slippery slope.” Fortunately, I still have my field notes, maps, and memories from those early days. The bulk of my early findings have never been published. With the benefit of LiDAR and other modern technology, a review of Vermont and neighboring literature, plus limited new, recent field mapping, as reported here, I have revisited this subject, leading me to a better understanding of the Pleistocene for the entire State of Vermont. I am now able to see Vermont glacial geology with new eyes. I have identified many different types of ice margin features, including features which mark the receding ice margin and show the manner of ice sheet recession, such as calving ice margins and large scale en masse stagnation related to physiography. I was able to correlate features across the entire State of Vermont, so as to delineate multiple ice sheet margins marking the recession of the ice sheet and as well correlate these with reported features in Quebec, New York, and New Hampshire. This shows the early development of nunataks in a “Nunatak Phase” and the progressive development of lobes, in a “Lobate Phase,” as depicted in great detail on maps for various “Locales” and as well more generally on Statewide ice margin maps. Further, I was able to identify and trace the readvance ice margin I had long ago recognized in the Missisquoi Valley, related to moraines nearby across the border in Quebec. This represents the last presence of the ice sheet in Vermont. This readvance occurred shortly after the opening of the Champlain Sea in Vermont which has been dated as about 13,000 years BP. Similarly, I was able to identify and map the earliest ice margins which can be correlated with features reported by others in New York and New Hampshire, including the White Mountain Moraine System, which has been identified as a readvance, dated as about 13,800 -14,000 years BP. Thus, the deglacial history of Vermont as reported here was bookended by readvances which took place at a late time in deglacial history with recession which was quite rapid. Further, the evidence indicates that this recession included large scale en masse stagnation of large portions of the ice sheet in the Connecticut Valley and as well the development of calving and associated destabilization of ice margins in the Champlain Valley. The evidence shows this history in great (almost overwhelming) detail.
I think of this as like solving pieces of a gigantic, three-dimensional spatial puzzle, in which time, representing the deglacial history element, is also a puzzling part. This is complex, especially given that many of the puzzle pieces are missing, and some require study as to how they were formed by the ice sheet or meltwater. The study of deglacial history is a process of fact finding and interpretation, the basic scientific process of hypothesis formulation and testing. When this works, which is not always the case, this can be great fun. And in fact my return to my academic roots has been quite enjoyable.
It turns out that this is a multifaceted story. It is of course fundamentally a history story. During the course of my study I had an epiphany, actually a series of multiple epiphanies My entire journey through Vermont’s late Pleistocene was a continual learning process, with many such epiphanies along the way. This report explicitly refers to such insights. For me, the realization that Vermont deglacial history came so late in the last glaciation, and occurred so rapidly was unexpected and quite surprising. But even more so is the information learned about how this occurred. This is essentially a story about the collapse of the ice sheet as it receded in Vermont, which is highly pertinent to modern day concerns about global warming. This story provides important insights which build upon and relate to recent findings about the nature of such collapses for present day ice sheets in today’s global warming. For me personally, while I love history and see my findings about Vermont’s deglacial history as important, the findings about how this took place, essentially the collapse of the ice sheet in Vermont, in the context of my concern for present day global warming, takes on an existential feel. In my opinion, this entire story, including the deglacial history and as well the ice sheet’s collapse deserves to be recognized and further studied.
In this report, I refer to “paradigms,” which are powerful ways of processing information, at the very heart of human thinking. But at times they limit our ability to see and understand what is before our eyes. It turns out that satisfying my curiosity required imagination to explore new paradigms, hence the quotes on the frontispiece of this report. These quotes are not intended to signify that others before or after me in the 1970s lacked imagination. Rather, they serve to remind me that my personal lack of imagination was a failing. Back then, in the old days, I could have done a better job, if only… . But, of course, it’s always easy to look back.
It turns out that the puzzle-picture coming from this study is new and different. Many puzzle pieces have fallen into place, painting a very different deglacial history than previously understood. This required serious effort on my part, and some fresh thinking.
As discussed in this report, this study examined deglacial history by the exploration of three elements, which have been inspired by Quebec research, specifically:
- A “Bath Tub Model,” in which elevation serves as a guide to correlate ice margins across the State;
- “Styles,” a term referring to the environmental conditions along these ice margins;
- “Glacial Dynamics,” the interaction between the ice sheet and its environmental setting, especially physiography and ponded water.
Together these three elements have helped me paint a new picture of deglacial history for the entire State of Vermont, with suggested correlations in neighboring regions.
For me, the finding that Vermont’s deglacial history is so young and took place so rapidly is quite surprising. I had assumed that the deglacial history of Vermont represented a more substantial portion of Pleistocene history. Further, the details about this recession found here are quite complex. A lot happened during the short time of this record! These findings for me are remarkable, and I believe represent a new and different understanding. Fortunately, by the time when the earliest ice margins in Vermont formed, the ice sheet had substantially thinned, making it possible to correlate ice margin features, as just noted, by usage of elevation as a guide. Now, finally, for me personally, the many puzzle pieces seem to have come together remarkably well, telling an intriguing story. As just stated, I looked at this just for the fun of it, the development of new hypotheses and the joy when sometimes these are confirmed. At this point I have satisfied my curiosity, with a better understanding of this history.
From my perspective, this report and the story it tells represent a beginning, not the final word on the matter, with many more details remaining to be fleshed out. While I believe that the deglacial history being presented here is reasonable and plausible, and makes geological sense, with many pieces fitting together, I see this as a hypothesis, deserving, if not requiring, further study. The job is not yet finished, but the general sense of Vermont deglacial history in a regional context is emerging. Again my fundamental interest in this endeavor was to satisfy my curiosity, personally for myself. My curiosity is now satisfied, and I am happy to leave it to others to continue with the exploration and refining (or revising) of this history. Hopefully my findings may provide insights for future research, because in my opinion more work certainly needs to be done. I see this report as a provocative guide, suggesting directions for future research.
The complexity of Vermont’s deglacial history made it more difficult to both think through and to write this report. I have struggled first to understand three dimensional and time transgressive issues, the puzzle story as just alluded to, and then how to express or convey these as accurately, clearly, and correctly as possible, and, believe it or not, given the length of my story-telling, which at times for me seems to drone on and on, I have tried to make it as simply, succinctly, and concisely as possible. Owing to the complexity of the deglacial history, again involving three dimensional and time-transgressive ice margin recession and as well relationships with multiple proglacial water bodies, the thinking through, writing, and then editing of this report has been challenging. Even now, after many read-throughs, I am realizing that this report is imperfect. Editing, it seems, particularly taking a new look with a “fresh face,” is never ending, which is my way of acknowledging that this report remains imperfect. I fundamentally like to write, which for me is a way of thinking. And this history has taken a lot of both thought and writing.
This report has the makings for some sort of publication, whether a book, memoir, or whatever. In my opinion, its thoughts, findings, ideas, etc. are intriguing and have merit. However, traditional academic publishing is not my interest or goal. I have decided to present my findings as a web site, given here as vermontdeglacialhistory.org. My purpose here with this report is to present my findings and to encourage open thinking and continued research whereby the ideas can be tested, refined, revised, or perhaps discarded. At this point in my life I don’t need another publication. I am more interested in having my findings be available to suggest possible directions for future research. And again, more research clearly is needed. I am content to leave it to others to carry on with the hard job of fleshing out and perhaps revising the story.
This report has not been peer reviewed. I understand the significance and importance of peer review, providing a mechanism by which the scientific validity of reported findings can be attested. But, because a) my findings substantially depart from the current mainstream thinking, and b) I have been away from research on this subject for a long time, peer review would take more time and effort than I have available or am willing to devote at this point in life. Fortunately, web site publication provides a way to make my findings broadly available, even if not part of the formal or “official” record. Thus, my goal is to simply present my findings here, to provoke further, new thought. I am OK with letting time and history be the judge of the merits of my findings.
My preference at an early time in this work was to somehow find a way for this to be a collaborative venture with others who have been toiling over these issues, in some cases since the time I left academia in 1980. With this in mind, I shared early drafts with several present-day researchers. Initially, I intentionally avoided inclusion of many of their previously published works, so as to be respectful and not tread on their toes. Unfortunately, this backfired, perhaps giving the impression that I was not aware, mindful, or respectful of their work. I very much regret this outcome, as I believe the end result would have been much better with collaborative thinking and input. This report has grown so large, that it has become difficult for me to see it with fresh eyes, which could have come from others.
I want to emphasize that I do not see this exploration of Vermont deglacial history as merely an academic matter, but rather as bearing on present-day concerns about global warming, which for me makes this enterprise more serious. The issue of global warming is discussed briefly in this report. I have added comments about what I believe the story about the recession of the Pleistocene Laurentide ice sheet in Vermont, as given here, may tell us about critical issues for global warming and its impact on modern ice sheets. Whereas I don’t claim to be an expert on global warming, that doesn’t stop me from thinking about my grandkids’ well-being. In my opinion, the Vermont deglacial history presented here has as much to say about modern day global warming, ice sheet instability, and sea level rise, as it does about past history itself.
This report also touches on early human, so-called “PaleoIndian,” migration and presence in Vermont, in as much as, for reasons briefly explained early archaeological sites tend to shadow ice margins of the receding ice sheet.
I am aware that this report could be substantially improved by both further research and more careful editing. I have made it the best I can, but this is a big job. “This ain’t purfect,” as my grandmother used to say about the large, complex quilts she used to patch together. For me, this study is like a large, very complex quilt. I am now an old dude who likes to bike ride and hike, paint, read, travel, and generally explore a myriad of interests. This report ain’t purfect and keeps getting in my way of doing other things. My apologies to the reader for mechanical errors, typos, mis-spellings, redundancies, etc. This document is so large that it is difficult for me to keep track of what I said in various sections, which is again an argument for a collaborative effort. Too many redundancies make for less enjoyable reading reading reading reading reading.! As already stated, my primary goal now is to encourage further research by others, to share my ideas. My goal is to make the information I learned available as best I can, as soon as possible, in a limited amount of time, in reasonably good form, so that I can get back to hiking, biking, painting, and other life pleasures with family and friends.
Whereas it is not my goal for this report to be the launch of a new career in an ongoing study, as I have other pressing interests as just stated, I would welcome any feedback, questions, or dialogue. I have the capability of making changes to this report or adding comments from others. My email address for such communication is: vermonticeman@gmail.com.
I am pleased by my findings, by what I have done, and what I have learned, my curiosity now finally being satisfied. But I have a problem. The telling of this story has now become like a book, so long, so convoluted, so filled with facts, thoughts, and ideas, both tiny and large, as is the nature of LiDAR-based research, making this a difficult read. Added to this are references to the names of villages, streams, drainage basins, and the like, with which most readers are unfamiliar, making this foreign and unfamiliar territory, compounding the readability challenge of this report. This outcome, its length and detail, reflects the fact that my study uncovered totally new information which I first had to study and explore and thereby decipher. This was the case for example for the identification of new types of ice margin features, such as “Scabby Terrain,” “Ice Tongue Grooves,” and multiple types of calving ice margin features, which are new and different puzzle pieces. Understanding the meaning of these features required me to study and learn their historical context. And likewise the telling of these features as well required advance explanation of the related history, even before the portion of my report describing this history, which led to redundancy and an even longer report. And for me, my problem was compounded by the fact that I found it necessary to write as I studied, having no idea where this was taking me. So, my report follows a path carved by the logic of discovery. Further, in writing this report I felt compelled to provide the evidence and basis for my findings so that the reader can judge their merit, leading to even more detail. I tried to improve this by using appendices for background information, but still this “book” is a long and difficult read.
Of course, I have edited and refined my findings, again and again. I liken this to a complex three dimensional puzzle in which overlapping, time transgressive temporal and spatial elements are part of the puzzle. Editing and refining itself is never ending; a new and better way of expression always and inevitably emerges, again and again, often with still more insights. Suffice it to say, this report is far too long, too convoluted, too complex, too “local,” etc. Most people with an interest in the subject simply will not be willing or interested enough to plough through this tome. Me too – I find it difficult to dig into and follow my own findings and writings. But again, the basis for my findings is provided by details, which I felt are needed given that this is the first comprehensive overview of the deglacial history for Vermont in its entirety, and introduces many new findings never before recognized.
I see the need for a condensed summary of the essential findings of this report. Unfortunately, at my age, at this point in my life, I do not see myself as carrying this forward. I’ve done what I could, as best I could, and am ready to move on. I will always look back through this journey with pride and satisfaction, that finally I now better understand this story. But, this story is not finished, as it never can be. Nevertheless, it’s time for me to move on. I invite someone else to take on the task of putting this story together in a more condensed and palatable form, preferably in conjunction with an academic program, preferably with students. Of course, I am available to help.
Regardless of whether or not a summary report is developed, this web site presents findings that will stand as part of the literature. As is the case for much of the work that has been published since my time at UVM, these findings are not peer reviewed and thus need to be tested. But as is the nature of story-telling done in a thoughtful, studied way, now told this story exists and can only be ignored to the extent it is flawed, and otherwise to do so reflects the ignorance and failing of the reader.
A hard copy pdf file of this tome is available, which can be provided through my above email address.
Finally, an expression of gratitude. To my son –a health economist at Stanford University and the Veterans Administration, who has been remarkably helpful and supportive with all sorts of suggestions about how to make this a better report. To my daughter – the CEO of one of the major philanthropic organizations in the country – whose managerial capability and spirit of giving stands as a role model for me. And most especially to my wife – my companion and supporter, even when I sometimes have become consumed by my “Projects,” such as this one. To all of you, Thanks!
W.Philip Wagner – Shelburne, Vermont January 30, 2026