Apparently there are very low tides tomorrow in the middle of the day -- so if you live in West Wales, it's the perfect time to have a look at the submerged forest, across which our Mesolithic ancestors used to roam.
The forest is present between the tide marks, but in the summer it is usually hidden beneath the beach sand (which, as any geomorphologist will tell you, accumulates in the summer and is washed out to sea in the winter.) So now is a perfect time, before beaches start to aggrade again. Tree stumps, branches, root systems, and even peaty beds with soft vegetable matter and nuts and seeds, can be seen. Generally the peat beds and traces of woodland vegetation are resting on either broken bedrock or glacial and fluvio-glacial sediments. In Newport Bay, a couple of weeks ago, I found quite a large expanse of Irish Sea till underneath the submerged forest -- quite close to the main car park for Traeth Mawr.
I have always dreamed of finding a skeleton, or a set of antlers, or maybe even a skull and horns belonging to some great beast, but the best I have been able to manage, after years of searching, is some hazel nuts with the nuts still intact inside the shells, some 7,000 years old........
8 comments:
Fascinating. I go to Amroth (near Tenby) where forest remains are visible for a long distance at low tide.
Any further news, identification-wise, as to the erratic you observed in the Newport estuary (previous Post in February)? Have you sent your samples off to a friendly rock specialist?
Brian,
Is 5000 BC the exact date do you think?
No -- the wooded area offshore must have spanned several thousand years, dating from a time when the climate was warm enough for extensive woodland growth after the onset of the Holocene, right up to the time when a particular area of woodland was finally overwhelmed by a rising sea level. There are lots of radiocarbon dates around 6000 BP - 4500 BP -- but others around 7,000 BP. At lower levels -- probably in areas now permanently submerged -- there will be forests that were older and were submerged earlier.
What is interesting is the carbon dates - 7000BP to 4500BP, which is when the sea level finally flooded this area after the great Ice Age melt like doggerland.
The reality of course is that from sea level data this was dry land for many tens of thousands of years. Covered in ice during the last major ice age, tundra thereafter and then finally green and pleasant land with trees as Wales and Ireland did not exist, as this area was part of a single land mass until 12,000BP.
Consequently, we should get RC dating going back a lot further - but we don't!
This shows that either it is only the last objects in prehistory of an ancient area that are left buried or swamped that we seem to find - rather than a staggered complete history OR that the separation was much later and the Sea level data is consequently wrong!
RJL
Minor details, Robert, in the way of comment.
The Doggerland flooding was not due to ice melting, rather to an undersea shift (earth quake/landslide) off Norway which gave rise to a Tsunami type effect. It happened suddenly and with catastrophic effect. Not sure how this would have effected West Wales as the net sea level was not influenced beyond the continuing glacial melting that eventually separated UK and Europe definitively.
The disconnect between Ireland and Wales happened earlier than 10k BC, I think, the last connection being in the North. Thus some people argue for a North to South colonization of Ireland rather than South to North. Still I puzzle about the folk memory in the Mabinogian that refers to walking between Ireland to Wales - how ancient is that?
I think Brian's input fits my understanding. The general sea level reached approximately current level around 2500 BC.
Chris -- Doggerland was flooded, like everywhere else around the shores of the UK, by the Holocene rise in sea level following deglaciation. There may have been minor events (including catastrophic ones) but this event was gradual and inevitable -- disturbed maybe in some details by eustatic / isostatic interactions. (That's because the northern part of the North Sea was depressed by glaciation, and then needed to recover afterwards by crustal uplift.)
Think we say the same, other than the tsunami would not have been minor for people caught in its path. They would have been torn apart.
So minor in a geological sense, catastrophic culturally.
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