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Discussion on NN6474
Soil piping and peat gully, lovely. Water flow potential and snow slump and melt. Masses on Black Mountains and Mid Wales, some Mendip, little soil on Exmoor, but great to see, sheep enjoy it for shelter and horses and cattle for track so it erodes into the gravels and rock bed, from whence the water flow energy gradient changes according to the RJ Chorley USGS 500B theory, then we have arroyo and Australian sediment and soil profiles cut out and the top of Kenya in the Tundra climate. The water then drains free and freezes into a low base level from a cut face of soil layers, so the pattern alters the hydraulic state, one reason why I avoided the south west side of Bryn Daith, Gwy, Plynlimon as that was cut through by track and gully, which interrupted the soil profile sequence in those days and obviously had waterfalls from it in summer 1968 after the Great Flodde Biscay generated Storms of Somerset that MD Newson and JD Hanwell were observing and I found out about on return and in 1969 1970 when they wrote their report. Anyway back to the gemorphology, the cut face tends to form a number of differing slotted and slip over plane slopes, so the system migrates backwards and basins of new material and vegetation open out, with whole ephemeral and headwater tributaries, which is why Tony Jones wrote stream channel initiation, that concentrates flow and flood potential increases especially with down stream congestion, lower valley areas improve in sediments and flood local zones, which brings us back to the theme of arroyo, Cooke and Reeves (later incised), Ellis, Grant on Oregon sands, the China loess studies of piping internal features. It moves, sometimes rapidly especially with flash floods, so do not enter a conduit unless ready for possible fall, large rock detachments if present as on Mendip north terrace where they hang from the cliff, or Portishead O.R.S. ledge that has now gone, and do not dig it out, people do become buried as in snow and silts, steadily and the hydraulics adjust. Never stand on the swallet sediment as it vibrates from flood waters flowing into it taking photographs. Good stuff, but unstable. Some can be seen at Loch Lundie and Skye approach of meandering rivers and the geology spread from Black and Red Cuillin along the river aka John Thornes 1969 again for Australia, while Strath Oykel is well worth the journey north. Wives be prepared for trek and hours of photographic experiences, sheep and hot cold and snow, rain experiences on narrow road bends and soggy forests. What happened to Afghanistan Kashmir I begin to wonder? Harvest Time for the Geomorphologists (Michael Caine and a Muppet). Talking of which the snow of course can then shelter from the sun and melt as long as the tunnelling melt water (Colorado, daughter taken pictures) does not erode it out from beneath, so we have winter spring summer accumulations (John Bailey comment 1982 massive freeze Sheepway Portishead Portbury, now a much greater mud slump). Never expect a snow slope anywhere to be stable as they noted in Mallory and Irving review and climb BBC 17 August 2011 and Bonington refers to many times. The best ever was probably Don Whillans climbing through sludge and vegetation Andes before they even reached the climbing rocks and ice. Evocative of "the environment" of montane structures. Guinea Pigs on Andean village slopes and Michael Douglas the slide down the ravine when the crest fell. Done that, does no good to your camera and clothing to be covered in mud from head to foot and that was only North Weston footpath. Mad way to work but we enjoy it!