Geograph - photograph every grid square

S Bend Afon y Waun Alan Bowring ... looking at Maplandia of this particular Loop de Loop (Pauline Collins) one could only guess this may be two, or originally one lobe, slumps, through which overflow eventually incised and cut into two, but some geologic and soils auger would assess whether this is old fault line, original river stream, general degrade of sediments on the plateaux and slips, the area is fascinating and a great drive, most meander have some historical slip feature as well as hydraulic deposition of older material. Thanks, I tracked it back from Methyr as Maplandia only recognises some main sites and many of those are of foreign copies. Good photograph. The whole sector right through Elan, Plynlimon, Brecon has many such good sites similar to this and with pothole scours local geologic materials basin sediments and peat moorland soils with variations in subsurface flows as you noted. Some are filled basin incised slots, that messes up Plynlimon geomorphology really well as it does walking along reaches, sumps they call them in cave swallet land of the south, Mendip, they have substantial seepage into subsurface conduits and fissures, some are mining ponds and social or farm alterations.
You could run an auger profile down the two slump ridges and to the north and perhaps south, although unless severely backwater affected that may not be necessary, thus revealing the layers in each apparent lobe and the upstream without, just rock base?, then plot the flows and sediment systems with materials, petrology, soil horizons, known farming and sequences geomorphic, especially the recent as the Black Mountains were severely affected by 1940s expansion for food yields with improvement grant assistance so much of their soils have to be carefully thought through as with Plynlimon drainage channels. Add a little review of Exmoor which has Drybridge slips, Kirkby, Curtis, Calver, Anderson, we put T-bars in for MJK and looked at podzol interflow prospects into the valley 1969, geograph SS 75 38 Guy Wareham, read LF Curtis and MJ Anderson A Calver and look at north coast slips which are quite dangerous and the Melange and Porlock slips as I did from 1955 motorbike pushing Porlock Hill, 1973 with Clare LS coast valley incisions scree, then 2006, and think about Austrian scree 1974 studied and Edward Watson 1967, do not fall off Black Mountains Grwyne Fechan and do note John Lewin and many basin alluvial drills (aka Taylor Kidson Bowen Davies Borth with UCW Geology) and you move toward a dissertation if you think about JAA Jones soil piping, one degree later you maybe appointed and sweltering through China and Afghan slides as Dave Petley. Anyway a small project maybe worth the visit. Mike best wishes! A lot of work yet to be completed! This is where Welsh Soils Discussion Group 1967 and careful staff ensure Research.