Talk:Finchley Gap

Latest comment: 3 years ago by Alan Mattingly in topic Actual route of the gap

Actual route of the gap

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I have not been able to find citations for the suggested route of the gap/ overflow channel. From looking at colour contour maps I conclude the most likely route of low lying land is from the R. Lee (once part of the Cole/Thames) , Pymmes Brook, through the low gap at New Barnet, then Dollis Brook and R. Brent. If anyone has access to material by Wooldridge or others that can confirm this then is can be added to the article.Lumos3 (talk) 21:49, 28 February 2016 (UTC)Reply

See:
(1) Wooldridge SW, Linton DL (1955), Structure, surface and drainage in South-East England. Philip, London
(https://archive.org/stream/structuresurface032810mbp/structuresurface032810mbp_djvu.txt)
CHAPTER VIII:
"At Finchley the ice occupied a broad depression between the high ground at Hampstead and Barnet respectively; the surface of the boulder-clay varies in height from 250-300 feet and the sub-drift surface is at 224 feet at Church End, Finchley.
"At the stage of the Lower Gravel Train" (a pre-Anglian deposit) "we can trace the Thames from Goring gap eastwards to the Colne valley... We have given reason to suppose that it then looped southwards across Middlesex by way of the Finchley depression" (then north-east through Enfield to its former course near Ware).
(2) Gibbard PL (1979), Middle Pleistocene drainage in the Thames Valley, Geological Magazine Volume 116, Issue 1 January 1979
(https://drive.google.com/file/d/1RAexpvlZ6T3hghv3wXZqPTKmggTvdQmf/view?usp=sharing)
"Recent studies (Gibbard, 1977) have shown that the Thames flowed through the Vale of St Albans, N of London, until the Anglian glacial stage and that it was never diverted into the Finchley or Middlesex depression in North London, as suggested by Wooldridge (1938,1960) and Wooldridge & Linton (1955)."
Gibbard showed that a proto-Mole-Wey river, with its source in the Weald, flowed through the Finchley depression prior to the Anglian ice advance, and headed north-east on a line through Southgate to Hoddesdon, where it joined the pre-Anglian Thames.
Alan Mattingly (talk) 14:06, 5 April 2021 (UTC)Reply
The above references have now been incorporated in the article. Alan Mattingly (talk) 15:45, 22 June 2021 (UTC)Reply