Shoreline ice accumulations in the Nares Strait

 

These slides are from the film "Beneath the Polar Sun" -- relating an attempt about ten years ago by a group of experienced kayakers to navigate the full length of the Nares Strait between North Greenland and Axel Heiberg Island.  They expected to find flat ice floes and intersecting navigable leads of clear water;  what they found was a nighmare of smashed ice fragments and brash ice stretching from horizon to horizon, with huge pressure ridges on long stretches of the shoreline.  They expected to travel 300 km. but gave up after 30 km of unremitting toil.

Ever since David Sugden and I wrote our extended report called "Coastal Geomorphology of High Latitudes" many years ago, I have been intrigued by the physical variations that exist in the real world of marine limits and raised shorelines.  There is quite enough variation is it is, on coasts where processes are determined by relatively ice-free conditions -- but things get vastly more complex where brash ice fragments or bergy bits are stranded on the shore.

Where an ice foot (or fringe of landfast sea ice) exists, there is considerable variation, partly dependent on the amount of brash ice or bergy bits incorporated -- derived from glaciers and icebergs.  And there is more variation again in freshwater environments like the shores of the Great Lakes, where much frazil ice may be incorporated, and where spectacular spring floods occur, such as in the St Lawrence and Mackenzie Rivers when the winter ice is flushed out with dramatic and sometimes catastrophic consequences.  Similar catastrophic spring floods also occur in the lower parts of the great  north-flowing Siberian rivers -- the Yenisei, Lena and Ob.  

In Antarctic raised beaches we often see pits and ridges on the pebble banks, with rapid lateral variations in beach sediments including particle size.  Bulldozed or pushed ridges of beach material are evidence of vast ice pressure on the shoreline associated with tidal streams or onshore winds;  accumulations of brash ice and pack ice fragments may be piled up to heights of 20m above HWM, forming more or less impenetrable barriers to access and causing damage to coastal infrastructure.  

One of our biggest fears when paddling om Nordvestfjord in 1962 was that an onshore wind might push all of the floating ice fragments in the fjord tight up against the shoreline, trapping us either inside or ourside the barrier.  Being trappped on the inside was preferable, but not to be welcomed.  But being trapped on the outside of a brash ice barrier was potentially lethal, since our canvas kayaks could not have coped with any attempt to paddle though it, and and neither could we have walked across it to the shore..........

The strange case of the missing Bulford post holes.......

Andy's attempts to fit assorted known pits at Bulford to a summer solstice line 

I refer to  a Facebook post by Andy Burnham (no, not that one --the other one) based on one of his Magalithic Portal posts.  Reprinted below with acknowledgement.

 I think it's fair to say that there is growing disquiet about the "summer solstice" post holes which Phil Harding claims to have found at Bulford in a dig that was completed almost a decade ago.  All very mysterious.  Andy is careful not to suggest, even very obliquely,  that the post holes do not exist, or that Phil has simply invented them, but it's very strange that nobody noticed, at the time of the dig or at the time of the Matt Lievers report in 2021, that there were two holes bigger and  different from all the others in their characteristics and which happened to lie on the (approximate) solar solstice alignment.......

Anjd why the emphasis on the exact 120m spacing? Is Phil suggesting that our clever ancestors were faliliar with the metric system of measurement?

It's too late now for anybody to go and check the evidence (which has in any case not been published) because there is now a housing estate on the site........

=====================

A fascinating midsummer solstice story as you no doubt saw - never has more excitement been generated over some Neolithic pits due to the Stonehenge connection and the careful 'silly season' timing. A deeper dive into what we know so far. Wessex Archaeology announced...

 1.  an alignment of two timber posts at Bulford, 120m apart, pointed to midsummer sunrise and midwinter sunset ~2950 BCE - a "prototype" solstice marker 500 years before the Stonehenge one. In the absence of the full publication I had a look at what's out there on the record. 

2.   This isn't a new dig. The Bulford pits were excavated in 2015-17 and published by Matt Leivers in 2021 (Internet Archaeology 56, free to read and very interesting). Linked at the end of this thread. The recent announcement seems to be a fresh reading of these same features.

 3.  Much was already in that paper: 48 pits on the hilltop dated ~2950 BCE, feasting debris and scatter leaning east towards Sidbury Hill. The solar interest was already on record. Even the star find. The "rare disc-shaped knife" now presented as a possible image of the sun's disc which is very easy to be sceptical about! - listed simply as "a discoidal knife" among the pit finds.

4.   But here's the gap. The structure actually being announced - two posts, 120m apart, on the solstice line - isn't described in the 2021 paper at all. 

5.  The post features Leivers does describe at Bulford don't match it: they're several centuries later (~2470-2570 BCE, not 2950) and much closer together (the nearest large pair about 64m apart, not 120m). Presumably there is now earlier dating for the two large 'alignment' pits

 6.  What is rather odd is how those two large pits were missed - Phil Harding spotted them from the unpublished work. 

7.  I tried to find the two posts on the published plan. I can't. (See the original post).  Every pit is shown as the same small dot, with 48 packed onto one hilltop. I plotted some 120m lines on the 50 degree solstice bearing - you can align this through dozens of pit pairs by chance... 

8.  So there's no picking the proposed aligned pair off the plan - far too many fit, and we're deliberately not proposing one. The actual two posts must have been singled out in the dig as large, deep post-holes, and that evidence just isn't on the published figure. 

9.  None of which makes it wrong of course - the setting is real, the date is real, the solstice bearing checks out. It's plausible and a comfortable fit with what's known - it's just running ahead of the published evidence presumably for the sake of that solstice announcement.

 10.  And fair play to them for getting the excitement in early - the detail is promised in a forthcoming Army Basing Programme volume (free via Wessex Archaeology's Open Library) and a Prehistoric Society piece. Until then it can't really be checked.

 11.  We await the publication with great interest. More on our new page for the the Bulford Neolithic Pits and Alignment which shows what must be the location for the alignment https://www.megalithic.co.uk/article.php?sid=63957 

12.  The location of the pits and alignment is close to the very nicely reconstructed henges which you can visit here: https://www.megalithic.co.uk/article.php?sid=60365 

13.   There's more in my forum post on the current gaps in the interpretation: https://www.megalithic.co.uk/modules.php?op=modload&name=Forum&file=viewtopic&topic=10434&forum=4  

14.  Here is the very interesting 2021 paper our pages were all based on, from Matt Leivers, which also discusses potential alignments on the Stonehenge cursus:  Stonehenge and the Emergence of the Sacred Landscape of Wessex Internet Archaeology 56. 

https://intarch.ac.uk/journal/issue56/2/index.html 

Why the regional marine limit (highest shoreline) is difficult to find

 

I came across this fabulous oblique aerial shot the other day, of part of the coast of Svalvbard.  I have labelled some of the features.

In the early days of our careers, David Sugden and I became quite good at finding the regional marine limit as we hoofed around in the landscape.  We discovered one marine limit at 134m in Kjove Land, East Greenland, in 1962, and then another one at the staggering  altitude of 275m at Noel Hill in the South Shetland Islands in Antarctica in 1966.  The altitudes were fixed with the most primitive surveying instruments coupled with barometric checks.  There were no detailed maps, and no GPS instruments in those far-off days.......

In the period since we did our fieldwork, as far as we know nobody has found higher marine traces in our fieldwork areas, or corrected our altitudes.

The marine limit in a glaciated landscape subject to isostatic adjustment or tectonic uplift is notoriously difficult to find.  The reason is explained in the photo above.  At the end of a glacial episode, as ice wastage speeds up and as isostatic uplift kicks in, very little of the coastline is initially subject to wave attack and other coastal processes.  That is becaused of the protection afforded to the coastline by a band of landfast perennial sea ice -- sometimes called the "ice foot".  It's very clear in the photo.  In the deepest valleys or fjords, flowing glaciers with floating snouts effectively protect coastal solid rock outcrops, and in other embayments seasonal sea ice may also afford protection.  We can see this situation at the left edge of the photo.

In the photo only one small coastal stretch is in contact with the open sea -- and this is where a range of coastal processes can operate -- just for a short time if isostatic or tectonic uplift rates are high.  So on the ground today we may find washed surfaces, small pebble banks or simply till deposits from which some of the finer sediments have been removed by wave action.  I recall many intense discussions with Dave while we tried to piece together the clues!  And because of the relatively great age of these high beach remnants, they have of course also been modified by post-glacial slope processes and frost shattering.

In the case of the South Shetland Islands, there was reasonable evidence of a short-lived ice advance over the marine shoreline traces.  It was clearly not very powerful, since the traces were well preserved.  Some have suggested that the "residual raised beach" that we described may be Plio-Pleistocene in age;  I disagree with that, since the remnants are so close to an ice edge that they cannot possibly have survived for that long, during multiple expansions and contractions of the  King George Island ice cap or indeed the regional ice sheet cover.  On the other hand, away from the areas of distinct ice streaming, island ice caps can expand to cover pereviously ice-free areas and can actually protect them.  So, on balance, in my 1971 paper I suggested that the Noel Hill resudual beach may well date from the last interglacial......... Eemian or Ipswichian.

Thus far, nobody, as far as I know, has managed to date these "high level" raised marine features which David and I described in our big paper in 1971........

See also:

https://brian-mountainman.blogspot.com/2025/02/the-noel-hill-residual-raised-beach.html

https://brian-mountainman.blogspot.com/2024/11/the-myth-of-ice-rafted-coastal-erratics.html

Another edifice built on the sinking sands

Summer solstice madness........

Today the media are carrying the latest fantastical story about the "Stonehenge prototype" found near Bulford.  The narrative is accompanied by much praise for the latest persistent and heroic archaeologist who features in video interviews -- this time not Indiana Jones or MPP, but Phil Harding

It has all been carefully planned by Wessex Archaeology, BBC and Channel 4,  Time Team and English Heritage.  There are excited reports all over the place, in social media and in the news outlets, about a newly discovered "structure" which showed that the locals were all very scientific and religious 500 years before the Stonehenge stone monument was thought of.  Apparently a new (old) circle has been discovered, including two prominent post holes that once held huge vertical wooden posts, and lots of other holes associated with assorted finds that demonstrate the presence of an organized and busy society.    In fairness to Phil Harding and the other archaeologists involved in the Bulford dig, they have not claimed that themselves, but have pointed out that the other pit traces are not on the circumference of a circle but are dotted around in several smallish groups.  The artifacts discovered are not that spectacular either, if truth be told.....

But the two wooden posts deemed to have been prominent features in the landscape are apparently aligned with the midsummer solstice sunrise and the midwinter solstice sunset.  So we are told by  Wessex Archaeology in their press release.  Apparently skyscape archaeologist Dr Fabio Silva has done the sums,  and the coordinates for the 2,950 BC horizon come out exactly right.  Well, not exactly, but almost.........  We are not shown any calculations, so we have to take it all on trust.

There isn't any article either.  We are told that there will be one somewhere, all in good time........  Neither is there a published excavation report that we can look at.

This is all completely unsatisfactory, and it is extraordinary that the media have regurgitated a Wessex Archaeology story that has not been adequately scrutinized by anybody, or even peer reviewed prior to publication.

So archaeology continues on its downwards spiral, preoccupied with banner headlines and heroic personalities -- and convinced that the media will regurgitate almost anything to do with Stonehenge, even where there is no supporting evidence at all in the public domain.

Greenland 1962: the new video

You may have noticed that the Greenland video which I posted a few days ago has now gone, to be replaced by this one.  When we posted the video called "Nordvestfjord Adventure" YouTube didn't like it at all, because we were using a very obscure name that nobody ever searches for............

So we were told in no uncertain terms that we had to ditch the name and "rebrand" the video so as to be more in line with the YouTube algorithms.  So here we are -- the original video with a new identity, and with a few extra editorial tweaks.  Anyway, hope you like it.  Please share if you wish.

Greenland 1962: into the world’s longest fjord

https://www.youtube.com/watch?v=zaF5J4KcQGw&t=25s

Greenland 1962: Into the world's longest fjord

 

Early glaciation ice rafting in the North Sea

Wroxham Crag deposits resting on chalk.  Bottom left is the modern beach.  

Location - Weybourne, Norfolk

This is a very interesting article that I missed in 2011 and came across in 2024:

https://brian-mountainman.blogspot.com/2024/11/ice-rafted-erratics-norfolk.html 

Suddenly it seems to have considerable relevance.  Sadly, the full paper still seems to be behind a paywall.   

Possible ice-rafted erratics in late Early to early Middle Pleistocene shallow marine and coastal deposits in northeast Norfolk, UK.
Nigel R. Larkin, Jonathan R. Lee & E. Rodger Connell

Proc Geol Assoc 2011

https://nora.nerc.ac.uk/id/eprint/14695/1/Larkin_et_al.pdf

Abstract

Erratic clasts with a mass of up to 15 kg are described from preglacial shallow marine deposits (Wroxham Crag Formation) in northeast Norfolk. Detailed examination of their petrology has enabled them to be provenanced to northern Britain and southern Norway. Their clustered occurrence in coastal sediments in Norfolk is believed to be the product of ice-rafting from glacier incursions into the North Sea from eastern Scotland and southern Norway, and their subsequent grounding and melting within coastal areas of what is now north Norfolk. The precise timing of these restricted glaciations is difficult to determine. However, the relationship of the erratics to the biostratigraphic record and the first major expansion of ice into the North Sea suggest these events occurred during at least one glaciation between the late Early Pleistocene and early Middle Pleistocene (c. 1.1−0.6 Ma). In contrast to the late Middle (Anglian) and Late Pleistocene (Last Glacial Maximum) glaciations, where the North Sea was largely devoid of extensive marine conditions, the presence of far-travelled ice-rafted materials implies that earlier cold stage sea-levels were considerably higher.

The evidence for a high sea level is quite convincing, as is the evidence of shallow marine conditions, sea floor deposits and contained dropstones weighing up to 15 kg.  The erratics are from Northern England and Norway.  The stratigraphic relationships indicate that the deposits (in th Wroxham Crag Formation) date from an early glaciation maybe a million years ago.  Samples came from West Runton and Sidestrand.

Preferred explanation of the occurrence of these erratics in beach and estuarine conditions:  "the far-travelled clasts were deposited by melt-out from (possibly grounded) icebergs in estuarine (Sidestrand) and beach (West Runton) environments with minimal local reworking. It is predicated on parts of the BIIS and SIS in northern Britain and southern Norway having floating ice margins within the northern and eastern North Sea Basin, upstream of which ice was actively eroding and entraining bedrock lithologies. This hypothesis is supported by both the clustered spatial and stratigraphic concentration of the erratics, and their frequently comparatively ‘fresh’ form. An ice-wedge cast penetrating the host deposit at West Runton indicates that the subsequent climate was sufficiently cold to support the development of permafrost after deposition of the erratic-bearing sediments."

Conclusions

Concentrations of erratics within WCF coastal deposits at Sidestrand and West Runton in northern East Anglia are considered the product of melt-out from (possibly grounded) icebergs.

The provenance of the erratics implies that these icebergs were derived from glaciers that were eroding bedrock in the Southern Uplands, Midland Valley and southern Grampian Highlands of Scotland, and Oslofjord in southern Norway.

The age of these erratic-bearing beds can be broadly constrained to a period from the late Early Pleistocene to early Middle Pleistocene interval (c. 1.1–0.6 Ma, a time period that spans the ‘Menapian’ (MIS 34)) to late ‘Cromerian Complex’ (MIS 16) stages.

These erratics demonstrate both the existence of restricted glaciations in Scotland and Norway, and their periodic expansion into the North Sea Basin prior to the maximum extent of the ice sheets during the Anglian Glaciation (MIS 12) of the Middle Pleistocene.

This research supports the work of Sejrup et al. (1987) and Ekman (1999) that argues that both the BIIS and SIS were active in the North Sea Basin on at least one occasion well before the Anglian stage of the Middle Pleistocene.

The deposition of the erratic-bearing beds during these early glaciations appears to coincide with higher glacial sea-levels than occurred during the late Middle and Late Pleistocene.

Like the authors of the paper, I am intrigued by the glacio-isostatic and eustatic interactions here on the west side of the North Sea, where one would not expect ice rafting and the dumping of dropstones during one or more glacial episodes -- at times when relative sea levels would have been far below present msl.  But here the features are, suggesting GLACIAL sea levels not far removed from those of today..................  and the authors are clear in their own minds that the features relate to marine conditions, not glacio-lacustrine conditions.

For many years there has been a widsespread belief that the North Sea Basin as a whole has been sinking tectonically while the western part of the British Isles has been slowly rising.  This means that deposits currently at sea-level were deposited at an even HIGHER level around a million years ago.  All very confusing.

I am checking out the current views on this paper, which was published 15 years ago.........