Langcliffe Pot
Encyclopedia
Langcliffe Pot is a cave system on the slopes of Great Whernside
in Upper Wharfedale
, about 2 km SSE of Kettlewell
in Yorkshire (UK NGR SD996711), and actually some 20 km NNE of Langcliffe
village. The cave entrance is at an altitude of 470m. The system has a total surveyed passage length of about 10 km, and a depth of only a little more than 100m. It was explored originally in 1936 and 1954 by the Craven Pothole Club (CPC), extended in 1968 by the Yorkshire Underground Research Team (YURT), and in 1968-70 by the University of Leeds Speleological Association (ULSA).
slab at the bottom of an otherwise unremarkable shallow shakehole north east of Fox Scar. A pitch of 30m leads to a traverse, then the start of 200m of wet crawling, Craven Crawl, the termination of the cave until 1968. Beyond Number One Junction, Stagger Passage leads 600m to Hammerdale Dub, and a junction with still larger passage continuing downstream. Some 1500m of streamway interspersed with boulder obstacles, Langstrothdale Chase, ends in a bedding plane crawl leading to Boireau Falls Chamber, 20m in diameter and 6m high, where the stream reappears and cascades into the boulders flooring the chamber. A complex boulder choke leads to a 20m pitch dropping into the Nemesis chamber. A massive collapse region, a tight and navigationally complex boulder choke, leads to Gasson's Series, initially high streamway, descending past Poseidon Sump and on into a procession of fine rift passage and chambers of the Agora, before turning east into Aphrodite Avenue, a handsome canyon with gour pools
, and the Silver Rake. The system comes to an end at a wall of sand and boulders, which can be bypassed to a smaller descending passage reaching a sump.
Notwithstanding its limited depth, a trip into the far reaches of Langcliffe Pot is still rated as one of the more serious undertakings in British caving. A detailed passage description and survey is given in Northern Caves. A survey in relation to the other caves of the Black Keld drainage system, and a detailed discussion of the geology and hydrology, is given in Limestones and Caves of Northwest England, Chapter 22.
, some 20 km2 in size, is a gathering ground for water entering the Langcliffe system, as well as the largest stream of the area which sinks into the ground at Mossdale Scar. Beneath Mossdale Scar, several entrances amongst a chaos of boulders unite close to the entrance to enter Mossdale Caverns
, a 10 km long complex system of underground passage. The Mossdale sink takes an average flow of 100 litres/sec, and resurges at Black Keld. Langcliffe Pot, which also feeds the Black Keld rising, terminate some 180m above, and several kilometres distant from it, leaving many questions about its detailed hydrology beyond the present limit of exploration. Surface sinks above Gasson's Series, for example, do not enter the Langcliffe system itself, but are diverted into separate cave systems by the layers of impervious strata above the Hardraw Limestone. Langcliffe Pot demonstrates the scale and complexity of the integrated cave system which must exist below the flanks of Great Whernside, a future challenge for sporting cavers and speleologists.
Great Whernside
Great Whernside is a mountain in the Yorkshire Dales, England, not to be confused with the better known Whernside, some to the west. Its summit is the highest point of the eastern flank of Wharfedale above Kettlewell...
in Upper Wharfedale
Wharfedale
Wharfedale is one of the Yorkshire Dales in England. It is the valley of the River Wharfe. Towns and villages in Wharfedale include Buckden, Kettlewell, Conistone, Grassington, Hebden, Ilkley, Burley-in-Wharfedale, Otley, Pool-in-Wharfedale, Arthington, Collingham, and Wetherby...
, about 2 km SSE of Kettlewell
Kettlewell
Kettlewell is a village in Upper Wharfedale, North Yorkshire, England. It lies between the villages of Grassington, Kilnsey and Conistone to the south, Starbotton to the north west, the hamlet of Horsehouse to the north east, and later on Coverdale...
in Yorkshire (UK NGR SD996711), and actually some 20 km NNE of Langcliffe
Langcliffe
Langcliffe is a village and civil parish in the Craven district of North Yorkshire, England it is situated to the immediate north of Settle.Notable residents or former residents of this village include authors Leah Fleming and Marina Fiorato-External links:...
village. The cave entrance is at an altitude of 470m. The system has a total surveyed passage length of about 10 km, and a depth of only a little more than 100m. It was explored originally in 1936 and 1954 by the Craven Pothole Club (CPC), extended in 1968 by the Yorkshire Underground Research Team (YURT), and in 1968-70 by the University of Leeds Speleological Association (ULSA).
Description
The Oddmire entrance drops below a limestoneLimestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
slab at the bottom of an otherwise unremarkable shallow shakehole north east of Fox Scar. A pitch of 30m leads to a traverse, then the start of 200m of wet crawling, Craven Crawl, the termination of the cave until 1968. Beyond Number One Junction, Stagger Passage leads 600m to Hammerdale Dub, and a junction with still larger passage continuing downstream. Some 1500m of streamway interspersed with boulder obstacles, Langstrothdale Chase, ends in a bedding plane crawl leading to Boireau Falls Chamber, 20m in diameter and 6m high, where the stream reappears and cascades into the boulders flooring the chamber. A complex boulder choke leads to a 20m pitch dropping into the Nemesis chamber. A massive collapse region, a tight and navigationally complex boulder choke, leads to Gasson's Series, initially high streamway, descending past Poseidon Sump and on into a procession of fine rift passage and chambers of the Agora, before turning east into Aphrodite Avenue, a handsome canyon with gour pools
Rimstone
Rimstone, also called gours, is a type of speleothem in the form of a stone dam. Rimstone is made up of calcite and other minerals that build up in cave pools. The formation created, which looks like stairs, often extends into flowstone above or below the original rimstone. Often, rimstone is...
, and the Silver Rake. The system comes to an end at a wall of sand and boulders, which can be bypassed to a smaller descending passage reaching a sump.
Notwithstanding its limited depth, a trip into the far reaches of Langcliffe Pot is still rated as one of the more serious undertakings in British caving. A detailed passage description and survey is given in Northern Caves. A survey in relation to the other caves of the Black Keld drainage system, and a detailed discussion of the geology and hydrology, is given in Limestones and Caves of Northwest England, Chapter 22.
Geology
The surface region displays the classical scar morphology of the Great Scar Limestone. The higher beds, of Yoredale Limstones, form wide benches separated by steep scars, and the highest of these, the Middle Limestone bench, is pitted with shakeholes and partially covered by peat, sphagnum bog, clay and sandstone debris. The majority of the Langcliffe cave system is developed within the Middle Limestone series, with visible horizons of shale, chert and fossil bands. The Nemesis Pitch cuts through an otherwise impervious layer of shale to enter the Simonstone Limestone, while Gasson's Series below is totally developed within the Hardraw Limestone. The Silver Rake is named after the vein of the North Mossdale suite which controls the direction of passage below the Agora.Hydrology
The catchment area of Great WhernsideGreat Whernside
Great Whernside is a mountain in the Yorkshire Dales, England, not to be confused with the better known Whernside, some to the west. Its summit is the highest point of the eastern flank of Wharfedale above Kettlewell...
, some 20 km2 in size, is a gathering ground for water entering the Langcliffe system, as well as the largest stream of the area which sinks into the ground at Mossdale Scar. Beneath Mossdale Scar, several entrances amongst a chaos of boulders unite close to the entrance to enter Mossdale Caverns
Mossdale Caverns
Mossdale Caverns is a cave system in the Yorkshire Dales, England. It is located about north of Grassington, and east of Conistone, where the Mossdale beck disappears beneath the ground into the caves at Mossdale Scar...
, a 10 km long complex system of underground passage. The Mossdale sink takes an average flow of 100 litres/sec, and resurges at Black Keld. Langcliffe Pot, which also feeds the Black Keld rising, terminate some 180m above, and several kilometres distant from it, leaving many questions about its detailed hydrology beyond the present limit of exploration. Surface sinks above Gasson's Series, for example, do not enter the Langcliffe system itself, but are diverted into separate cave systems by the layers of impervious strata above the Hardraw Limestone. Langcliffe Pot demonstrates the scale and complexity of the integrated cave system which must exist below the flanks of Great Whernside, a future challenge for sporting cavers and speleologists.