Short Drop Cave - Gavel Pot System

Short Drop Cave - Gavel Pot system
Map showing the location of Short Drop Cave - Gavel Pot system
Location Leck Fell, Lancashire, England
OS grid SD 67026892
Coordinates 54°12′18″N 2°30′25″W / 54.205079°N 2.506952°W / 54.205079; -2.506952Coordinates: 54°12′18″N 2°30′25″W / 54.205079°N 2.506952°W / 54.205079; -2.506952
Depth 212 metres (696 ft)
Length about 3.5 kilometres (2.2 mi)
Elevation 323 metres (1,060 ft)
Discovery 1885
Geology Carboniferous limestone
Entrances 4
Hazards verticality, water
Access CNCC Permit

Short Drop Cave and Gavel Pot are different entrances into the same cave system on Leck Fell, in Lancashire, England. The main top entrance, Short Drop Cave, is a small hole in a fenced off shakehole near the main stream sink; Gavel Pot, a window into the system, is a large fenced shakehole some 40-metre (130 ft) deep requiring tackle to descend. There are two other smaller entrances into Short Drop Cave. At it base the system links via a sump with Lost Johns' Cave, and is part of the Three Counties System, an 87 kilometres (54 mi) cave system which spans the borders of Cumbria, Lancashire, and North Yorkshire.[1]

Description

The main entrance into Short Cave is at the end of a shallow valley where a small hole drops into a stream passage. Upstream leads to a canal passage which becomes too tight, although an excavated squeeze on the right before the end leads to the Coal Hole entrance. Downstream, 100 metres (330 ft) of mainly low passage leads to an oxbow with a larger passage arriving from Rift Entrance. A long awkward inlet passage called Masochist Passage can be followed to the north-east for some 300 metres (980 ft) almost up to the Rumbling Hole stream sinks, and an old high level route named Ancient Highway loops back to the main route.

Downstream continues as a canyon passage which steadily enlarges, passing an inlet passage on the left where the main water enters which can be followed up to where it becomes choked with boulders underneath the stream sink. The main passage continues for about 300 metres (980 ft) up to 15 metres (49 ft) high and 5 metres (16 ft) wide, under a boulder bridge wedged across the passage, to finish in a choke in a roof chamber. The water then follows a narrow meandering canyon to the first waterfall pitch of 5 metres (16 ft), and continues to a second pitch of 8 metres (26 ft) at the base of which the water disappears into a choked sump pool. A traverse can be followed over the top of the pitch round to where a pitch enters from the Gavel Pot doline.

Rift Entrance (54°12′16″N 2°30′25″W / 54.204478°N 2.506837°W / 54.204478; -2.506837 (Rift Entrance)) is a currently blocked entrance just over the wall from the main sink. A climb down enters a rift chamber, where a passage enters the First Oxbow in Short Drop Cave.[2]

Coal Hole Entrance (54°12′22″N 2°30′17″W / 54.206118°N 2.504784°W / 54.206118; -2.504784 (Coal Hole Entrance)) is located in a small shakehole SE of Rumbling Hole. A long crawl eventually reaches a bedding chamber with a coal seam exposed in the walls where an excavated squeeze drops into Canals Inlet in Short Drop Cave.[3]

Gavel Pot (54°12′22″N 2°30′48″W / 54.206146°N 2.513413°W / 54.206146; -2.513413 (Gavel Pot)) consists of a steep-sided shakehole some 140 metres (460 ft) deep, and 140 metres (460 ft) in circumference - reputedly the largest shakehole in England.[4] Scrambling down the eastern side, a ledge is reached where an 8 metres (26 ft) pitch lands at the end of the traverse from Short Drop Cave. In the other direction a high canyon passage soon enters the bottom of the Gavel Pot shakehole, overlooked by rocky ramparts. In the corner a further 8 metres (26 ft) pitch over a chockstone lands in a chamber where an excavated 10 metres (33 ft) drop lands in the main passage. The water from Short Drop soon enters from the right, and a large collapse from Ash Tree Hole on the surface is passed on the left. The passage develops into a canyon, and drops down two well-watered shafts of 26 metres (85 ft) and 17 metres (56 ft). The final one lands in a chamber with a sump pool, which is a window into the underwater passages carrying water from Notts Pot to the resurgence at Leck Beck Head. Upstream has been dived for 120 metres (390 ft) to a shaft 60 metres (200 ft) deep. At the bottom a descending passage chokes at a depth of 64 metres (210 ft), the deepest point in the Three Counties System.[5] The main downstream has been dived past a junction at 198 metres (650 ft). Upstream here emerges at the downstream sump of Lost Johns' Cave after 15 metres (49 ft). Downstream has been dived for some 1.7 kilometres (5,600 ft), past an inlet from Pippikin Pot, to the resurgence, much of it at 30 metres (98 ft) depth.[6]

A window in the upper part of the main passage leads through a series of well decorated chambers called Glasfurd's Chamber.[5]

Geology and Hydrology

The cave is a solutional cave formed in Visean Great Scar limestone from the Mississippian Series of the Carboniferous period. The various abandoned passages in Short Drop Cave show that it is has a long history, but the current drainage flows through the main passages of Short Drop Cave and Gavel Pot to join the main Ireby Fell Cavern - Notts Pot water at the base of the cave, where it flows through to its resurgence at Leck Beck Head. The position and orientation of the main system is thought to have been influenced by a gentle syncline plunging towards the north-west, and the height of the development of Short Drop Cave has been influenced by a major inception horizon between the Lower Hawes and Goredale Limestones, identifiable by a thin bed of shale and sometimes coal.[7] Glasfurd's Chamber is thought to be part of a major phreatic passage formed some 350,000 years ago, that took water from a major sink at Rumbling Hole, through Death's Head Hole and Glasfurd's Chamber, and hence to a resurgence in the Leck Beck valley some 100 metres (330 ft) above the current resurgence which is now covered with glacial till.[8]

History

The first recorded exploration of the Gavel Pot - Short Drop system was in 1885, when the Gritstone Club descended one of the entrances in the Gavel Pot shakehole, and explored Short Drop Cave for a considerable distance upstream, using a ladder to scale the 5-metre (16 ft) high waterfall.[9] They referred to the cave as "Low Douk Cave" probably mistakenly, as it had been called "Gavel-pot" in 1842 by Jonathan Otley,[10] and in 1881 Balderstone referred to it as "Gavel or Navel Pot".[11] Short Drop cave was explored through to Gavel Pot by a Yorkshire Ramblers' Club party in 1898.[12] The University of Leeds Speleological Society undertook a major survey of the system in 1965, and pushed a lot of inlets and high level passages including Masochist Passage and the Ancient Highway, to extend the cave to a length of 2,250 metres (7,380 ft).[13] The Coal Hole entrance was explored to Short Drop in 1977 by the Cave Projects Group.[14]

The main passages in Gavel Pot were first explored in 1970, when the Northern Pennine Club excavated a shaft in the final chamber.[15] The upstream terminal sump was originally dived by Dave Yeandle. Geoff Yeadon descended the sump to a depth of 41 metres (135 ft) in 1974,[16] and the shaft was finally bottomed in 1985 by Rob Palmer.[17] The downstream underwater connection with Lost Johns' Cave was made by Bob Churcher in 1975,[18] and with Pippikin Pot in 1989 by Geoff Yeadon.[19]

References

  1. ↑ Allen, Tim (Feb–Mar 2012). "The True Length Unravelled". Descent (224): 24–25.
  2. ↑ Brook, Dave; Griffiths, J; Long, M.H.; Ryder, P.F. (1994). Northern Caves. Volume 3. The Three Counties System and the North-West. Dalesman Publish Company. p. 113. ISBN 1855680831.
  3. ↑ Brook, Dave; Griffiths, J; Long, M.H.; Ryder, P.F. (1994). Northern Caves. Volume 3. The Three Counties System and the North-West. Dalesman Publish Company. p. 90. ISBN 1855680831.
  4. ↑ Thornber, Norman (1965). Pennine Underground. Clapham, Lancaster: Dalesman Publishing Company. p. 78.
  5. 1 2 Brook, Dave; Griffiths, J; Long, M.H.; Ryder, P.F. (1994). Northern Caves. Volume 3. The Three Counties System and the North-West. Dalesman Publish Company. pp. 92–93. ISBN 1855680831.
  6. ↑ Hill, Elaine; Adrian, Hall (2015). Northern Sump Index 2015. Cave Diving Group. pp. 104–106, 224–227, 379–382. ISBN 9780901031082.
  7. ↑ David Lowe (2004). "Inception of Caves". In Gunn, John. Encyclopedia of Caves and Karst Science. New York: Fitzroy Dearborn. p. 952. ISBN 1-57958-399-7.
  8. ↑ Waltham, A.C. (1974). Limestone and Caves of North-West England. Newton Abbot: David & Charles. pp. 289–290. ISBN 0715361813.
  9. ↑ Hastings, C. (1930). "Gavel Pot in 1885.". Yorkshire Ramblers' Club Journal. Leeds: YRC. 6 (19): 60–62. Retrieved 30 July 2015.
  10. ↑ Otley, Jonathan (1842). A descriptive guide to the English Lakes and Adjacent Mountains (Seventh ed.). London: Simpkin, Marshall, & Co. p. 200. Retrieved 11 July 2015.
  11. ↑ Balderstone, Robert R; Balderstone, Margaret (1881). Book, Ingleton, Bygone and Present. London: Simpkin, Marshall and Co. p. 73.
  12. ↑ Cuttriss, S.W. (1922). "The Leck Fell Pot-Holes". Yorkshire Ramblers' Club Journal. Leeds: YRC. 5 (15): 60–64. Retrieved 14 July 2015.
  13. ↑ "Short Drop Cave". University of Leeds Speleological Society Explorations Journal: 90. Oct 1969.
  14. ↑ "Work in the Dales". Sheffield University Speleological Society Jounal. 3 (1): 50–52. 1980.
  15. ↑ Smith, B. "GAVEL POT". Northern Pennine Cub Archives. Retrieved 30 July 2015.
  16. ↑ "Geoff Yeadon Breaks Two Diving Records". Descent (31): 25. May–June 1987.
  17. ↑ "Gavel Pot sump bottomed at 207 ft - a British record dive on air". Descent (67): 13. Nov–Dec 1987.
  18. ↑ "Digs and Discoveries". University of Leeds Speleological Society Review (14). Aug 1976.
  19. ↑ "The Pippikin Connection". Descent (89): 16. Aug–Sep 1989.
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