Gradually I am placing all of my published glacial geomorphology articles onto the web, using the Researchgate vehicle. There are still a few gaps, but we will get there........
I wish that Ixer and Bevins are various others would do the same; too many specialist articles are hidden behind paywalls, which means that effective scrutiny becomes impossible except for those who belong to academic institutions or who are prepared to pay £25 (or whatever) for the privilege of reading something.
Anyway, at long last I have managed to upload a crucial paper published in "Nature" in 1965, which caused quite a stir at the time because it was the first article to seriously question the Older Drift /Newer Drift scenario for the western parts of the British Isles, the first article to demonstrate that the South Wales End Moraine of Charlesworth was not actually an end moraine or glacial limit at all, and that the last glaciation of South Wales and Southern Ireland was very recent indeed in geological terms -- namely around 20,000 years ago. It also used radiocarbon dating evidence from bulk samples, which was bound to be controversial at a time when radiocarbon dating was in its infancy -- but I stuck to my guns on the reliability of the dates because I knew they were supported by the Quaternary stratigraphy. And as we know, stratigraphy never lies (well, hardly ever.........).
There were some fairly high profile ripostes (in print and in conference discussions) from assorted researchers whose own favourite hypotheses were threatened by my research findings, but by 1968 many other researchers were finding from their research in southern Ireland, the Welsh Borders, North Wales and elsewhere that their glacial deposits were the same age as mine, and that their radiocarbon dates showed that mine were as reliable as theirs.
Ah, happy days! By the way, Main Wurm = Late Devensian. Anyway, here is the info:
A Possible Main Wurm Glaciation in West PembrokeshireJuly 1965
Nature 207(4997):622-623
DOI:
10.1038/207622a0
Brian John
Two carbon-14 age determinations from marine mollusc fragments in glacial outwash in Pembrokeshire have indicated that the last glaciation of West Wales from the Irish Sea probably occurred within the past 38,000 years. Bulk samples were required by the laboratory, so there were many fragments in each sample; the dates are "aggregate dates" taken from fragments of different (but probably not widely differing) ages. There is no reason to doubt the reliability of the age determinations, which confirm ice-free conditions in the Irish Sea and Cardigan Bay during the middle part of the Wurm glacial episode. The shell samples from Mullock Bridge in south Pembrokeshire and Trellys in north Pembrokeshire indicate a similar interglacial / glacial history at each site. This means that the "South Wales End Moraine" of Charlesworth does not delimit the maximum extent of glacier ice during the last glacial episode. Further, it is suggested that the extent of the Main Wurm Irish Sea Glacier was greater than has been previously assumed, and that the "Older Drift" area incorporates at least some expanses of relatively recent glacial deposits.
At Cil-maenllwyd (Cardiganshire) glacial outwash sands were found to contain layers of small wood fragments. A radiocarbon age determination of 33,750 yrs B.P. indicates that the wood fragments are probably of Middle Würm age, and that the last glaciation of St. George's Channel occurred during the Main Würm. Pollen and spores contained in the sands suggest that the environment prior to the last glaciation was at one stage predominantly forested. The organic remains are thought to relate to the problematical “ Middle Würm Interstadial ”, rather than the Paudorf Interstadial.
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