https://brian-mountainman.blogspot.com/2019/10/new-atlas-chapter-now-available.htm
https://www.researchgate.net/publication/336399326_The_Ice_Age_in_Pembrokeshire
Anyway, it's good to see a renewed interest in this topic, especially in the West Midlands -- and there are several new papers in the literature which present convincing new evidence.
The old idea about the extent of Wolstonian ice looked like this:
I have criticised that line many times as being glaciologically highly unlikely, if not impossible, at least with respect to the ice edge as portrayed for Wales. The new work in the West Midlands has adjusted the Wolstonian line as on this map:
This pushes the Anglian ice edge to the north in the Severn Valley, and pulls the Wolstonian line all the way south to the Cotswolds, as far as Moreton-in-Marsh. The authors argue for a powerful ice stream coming from North Wales. This makes perfectly good sense, since if there was ice in the lower Severn valley at the time, the Welsh ice cap must have been both thick and extensive.
This is an interesting development.
Here are the details for this paper published in June 2022:
Sebastian M. Gibson,
Mark D. Bateman,
Julian B. Murton,
Timothy T. Barrows,
L. Keith Fifield and
Philip L. Gibbard
Published:29 June 2022
Royal Society Open Science
Abstract
Glaciation during the late Middle Pleistocene is widely recognized across continental northwest Europe, but its extent and palaeoenvironmental significance in the British Isles are disputed. Although glaciogenic sediments at Wolston, Warwickshire, in the English West Midlands, have been used to define the stratotype of the Wolstonian Stage, their age has been variably assigned between marine isotope stages (MIS) 12 and 6. Here we present sedimentological and stratigraphical observations from five sites across the English West Midlands whose chronology is constrained by new luminescence ages from glaciofluvial sediments, supplemented by cosmogenic 36Cl exposure dating of erratic boulders. The ages suggest that between 199 ± 5 and 147 ± 2.5 ka the British Ice Sheet advanced into the English West Midlands as far south as Moreton-in-Marsh, Gloucestershire. This advance is assigned to the Moreton Stadial of the Late Wolstonian Substage. Dating of the glaciation to this substage allows correlation of the Moreton Stadial glacial deposits in the English West Midlands with those of the Drenthe Stadial during the Late Saalian Substage across continental northwest Europe.
Abstract
Glaciation during the late Middle Pleistocene is widely recognized across continental northwest Europe, but its extent and palaeoenvironmental significance in the British Isles are disputed. Although glaciogenic sediments at Wolston, Warwickshire, in the English West Midlands, have been used to define the stratotype of the Wolstonian Stage, their age has been variably assigned between marine isotope stages (MIS) 12 and 6. Here we present sedimentological and stratigraphical observations from five sites across the English West Midlands whose chronology is constrained by new luminescence ages from glaciofluvial sediments, supplemented by cosmogenic 36Cl exposure dating of erratic boulders. The ages suggest that between 199 ± 5 and 147 ± 2.5 ka the British Ice Sheet advanced into the English West Midlands as far south as Moreton-in-Marsh, Gloucestershire. This advance is assigned to the Moreton Stadial of the Late Wolstonian Substage. Dating of the glaciation to this substage allows correlation of the Moreton Stadial glacial deposits in the English West Midlands with those of the Drenthe Stadial during the Late Saalian Substage across continental northwest Europe.
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