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Summary Full report
Marlbank-Cuilcagh Mountain Region; Prod's Pot - Cascades Rising Area
Rec. Number:1155File Number:  
Locality Type:Karst Status:
Grid Reference: H1333 Approximate
County: Fermanagh District:Fermanagh District Council
Period:Quaternary, Carboniferous
Stages:Asbian, Holocene, Visean
Lithostrat:Dartry Limestone Formation, Glenade Sandstone Formation, Glencar Limestone Formation, Knockmore Limestone Member, Meenymore Formation
Site Description

Surface karst: Prod's Pot and Dooneen Rattling Hole depression.
The Prod's Pot-Cascades Rising system is a superb example of a fracture controlled dendritic river cave system. The system is the third deepest and longest in Northern Ireland and the seventh longest and deepest in Ireland. The entrance series of Cascades Rising Cave is the only known major cave development within the interbedded shales and limestones of the Glencar Limestone Formation. Features present within the system include well developed speleothems, perched phreas, fracture and bedding passage control, partial dolomitization along faults, roof collapse along shale bands and abandoned stream passages. The cave and surface karst are, at present, in a very good state of preservation.
The Prod's Pot-Cascades Rising Karst area lies between the Tullyhona and Marble Arch areas. The area contains one major cave system, the Prod's Pot-Cascades Rising Cave System and a large number of minor sites associated with this. The known cave system lies within Brookfield, Dooneen, Gortmaconnell, Legahorna, Leefa and Skreen townlands (Sheet 243), although recent tracing experiments have demonstrated that water sinking some considerable distance from the known cave rises at Cascades Rising.
History of Exploration: Prod's Pot was excavated and explored by the Reyfad Group in 1970. The various tributary sumps and passages beyond were dived by the CPG in 1971 and 1972. The complex and difficult downstream sumps were passed by the CDG in 1976 and the passages beyond these were explored downstream to the Cascades entrance series. Following this, the entrance to Cascades Rising Cave was excavated by the Reyfad Group later that year and the difficult entrance series was passed. The Prod's-Cascades through trip was finally completed by D. Woods and M. Campbell (Reyfad Group & CDG) in 1979.
Major speleological sites: Prod's Pot (H1364 3371) - Cascades Rising (H1228 3498) System (4100m+ long, 94m deep), Gortmaconnell Pots (H1363 3342), Goat Pot (H1578 3133).
Minor speleological sites: Smokey Mountain Sink (H1399 3003), Harry Jaques Memorial Cavern (H1421 3326), Pelvis Pot (H1412 3359), Westminster Dig (H1403 3361) and numerous unnamed sinks in Brookfield townland.
Total surveyed cave: ~4500m.
Prod's-Cascades catchment area: ~9.5km2 (excluding Goat Pot).
Total flow at rising (normal conditions): The DOE (NI) water service extract 1.2-1.6 million litres per day indicating an average flow of 0.014-0.02 CuMecs (Cubic metres per second).
I - Hydrology
Prod's-Cascades has a complex hydrology with water entering the system from some unexpected sources. Point input is derived from sinks in the Gortmaconnell-Dooneen-Brookfield area such as Gortmaconnell Pot, Little Gortmaconnell Pot, Smokey Mountain Sink
Surface karst: Smokey Mountain Sink.
and a number of minor unnamed sinks (e.g. Brookfield Sink 3, Brookfield Sink 8). A significant tributary enters from the surface via the Dooneen Rattling Hole-Prod's Pot Entrance doline. Water sinking in the streambed of the Owenbrean River and a sink to the east of Trien Hill (Goat Pot) has also been traced to Cascades Rising.
No major streams are encountered downstream of Papist Passage although there are a number of small inlets in the Main Stream Passage and in the upper reaches of Cascades Rising Cave (notably the Withywindle Inlet). These small inlets are probably derived from minor stream sinks or diffuse input. All the water encountered in the Prod's-Cascades system resurges at Cascades Rising in the Cladagh Glen.
II - Underground Karst
Prod's Pot-Cascades Rising Cave System
The cave system is developed within limestones of the Knockmore Limestone Member, with the exception of the entrance series of Cascades Rising Cave which is developed in the Glencar Limestone Formation. The system can be accessed via two entrances; Prod's Pot gives access to the passages upstream of the Main Stream sumps and Cascades Rising Cave gives access to the passages between Main Stream Sump 6 and the resurgence.
(i) Prod's Pot
Prod's Pot is entered via a small doline adjacent to Dooneen Rattling Hole. A series of five generally tight pitches, totalling 54m, gives access to the Main Stream Passage.
Prod's Pot: Main Stream Passage, downstream of entrance pitch.
Upstream, from the point where the main stream is entered from Prod's Pot, a short low section leads to a larger passage where a 10m long inlet enters from an aven. The main passage alternates between short low bedding controlled sections of passage and chambers where diffuse input enters via a large number of avens. A major tributary enters from Formation Passage to the south. Formation Passage extends for ~200m to a junction with a stream entering from a sump to the west. A well decorated passage continues at the junction to a boulder choke.
Prod's Pot: Boulder Hall

Prod's Pot: east passage wall in Boulder Hall.
Beyond the sump approximately 300m of well decorated passages have been explored, ending in a choke and a tight, partially gravel choked sump.
Upstream from the Formation Passage junction, the Main Stream Passage consists of 45m of low wet passage to the Minaret, a large calcite column.
Prod's Pot: The Minaret.
The crawls continue to a large rift passage and the Black Hole, where the passage sumps. Immediately before the Black Hole is reached, a large stream enters from Cascades Inlet Passage, a well developed active canyon passage ending in a sump.
Prod's Pot: Cascade Inlet Passage.
Beyond this sump are approximately 500m of tight rift passage with many sharp projections on the wall.
Downstream the main stream follows a large meandering passage. After 80m a major tributary, Papist Passage, enters from the south.
Prod's Pot: Main Stream Passage, downstream of Papist Passage.
This trends towards Pollasumera for 200m and ends in a sump. 50m into Papist, a small tributary enters from the east. This can be followed for 50m to a junction, both passages leading from this becoming constricted and impassable. A further 80m downstream from the entrance to Papist Passage, Bleeding Heart Passage enters from the northeast. This is 40m long and contains large amounts of fine, pale grey mud and a distinctive red formation. The Main Stream Passage continues for approximately 450m, mostly as large fracture controlled meandering passage, with a short canal section and a large chamber with an impressive stalagmite column, the James Connolly Memorial Column.
Prod's Pot: flow stone on west wall of Main Stream Passage at James Connolly Memorial Column.

Prod's Pot: James Connolly Memorial Column.

Prod's Pot: speleothems below James Connolly Memorial Column.
About 550m from the entrance the roof drops to a duck, followed by a chamber and Sump 1. This passage contains well preserved mud and calcite ledges, some 4m above the current stream level. (ii) Cascades Rising Cave The entrance to Cascades Rising Cave is at the head of a small dry river bed approximately 30m above and just south of The Cascades in the Cladagh Glen. A steep tight descent gives access to the stream. The initial 150m of passage, termed the Entrance Series, is a complex maze of low wet passages formed in the Glencar Limestone Formation.
Cascades Rising Cave: Entrance Series Passage in Glencar Limestone.
At 150m from the entrance, a short section of larger passage (just past the Letterbox) is formed within well bedded carbonate mudbanks and thin (1mm) shales of the Knockmore Limestone. At the end of the Entrance Series the passage enlarges dramatically as massive mudbank limestones of the Knockmore Member are reached. This is followed by the Boulder Series, large (10m x 15m passages) characterised by massive boulder breakdown.
Cascades Rising Cave: speleothems in Boulder Series Passage.

Cascades Rising Cave: speleothems in Boulder Series Passage.

Cascades Rising Cave: speleothems in Boulder Series Passage.

Cascades Rising Cave: speleothems in Boulder Series Passage.
The Boulder Series ends with a 5m climb down into the Main Stream Passage which can be followed for 700m upstream to Sump 8. The Main Stream Passage is a large (3m x 10m initially, then averaging 3m x 5m), well decorated passage
Cascades Rising Cave: flowstone in Main Stream Passage, downstream from the Canals.

Cascades Rising Cave: Main Stream Passage, downstream from the Canals.

Cascades Rising Cave: Main Stream Passage, downstream from the Canals.
with a large chamber containing extensive well bedded sediment banks including bedded sands and fine grey laminated clays. These sediment banks have been eroded at one side by the stream. After approximately 450m the Main Stream Passage leads to The Canals, 150m of low passages where the stream flows over active sand deposits in the stream bed. The passage again increases to its previous proportions, before a point is reached where the floor and roof dip sharply downwards and the passage sumps (Sump 8). Immediately before Sump 8 an inlet, the Witheywindle, enters from the east marking the start of the Sump Bypass Series. Some 200m of rift passage with sand floor can be followed to a small Sump from which the Witheywindle stream enters the passage. The passage continues to Creatures End, a large 50m+ high aven. The passage immediately preceding Creatures End contains many fine mud and calcite speleothems on the floor of the passage including two nests of cave pearls and mud "splattermites" and conulites.
Cascades Rising Cave: Witheywindle Inlet, mud formations.

Cascades Rising Cave: Witheywindle Inlet, cave pearls.
From Creatures End a low muddy bedding plane (Leprechaun Crawl) leads back to the main streamway. From this point the streamway can be followed east (to Sump 6) or west (to Sump 7). It is similar to the Main Stream Passage after the boulder series. (iii) Minor Speleological Sites Gortmaconnell Pot-Little Gortmaconnell Pot:- Gortmaconnell Pot and Little Gortmaconnell Pot consist of a complex of vertical shafts reaching a depth of approximately 50m, with some 140m of horizontal development, mostly active although a number of sand choked phreatic tubes of ~3m diameter have been intersected by the vadose shafts. The streams sinking at this point are presumed to enter Prod's Pot in Formation Passage. Brookfield Pots:- There are a large number of sinkholes and dolines in Dooneen and Brookfield townlands, many of which have significant cave development associated with them. Much of the water sinking in this area has been traced to Cascades Rising (Gunn, 1985). III - Surface Karst Surface karst features associated within the catchment of Cascades Rising largely consist of extensive, well developed sinkhole areas to the south and southeast of Prod's and solution doline fields, developed above the known cave passages. (i) Tufa There are significant deposits of tufa in the Cladagh Glen. These deposits are on the outcrop of the Glencar Limestone on the east side of the glen south of Cascades Rising. Additional deposits may be present in other sections of the glen.
The Prod's Pot-Cascades Rising System and associated sinks are an extensive, virtually undamaged, upland, dendritic karst drainage system. The system contains many classic speleogenetic features and speleothems. It is one of the three major carbonate mudbank hosted cave systems in the Marlbank area and is the only system with extensive cave development within the Glencar Limestone Formation. Little formal research has been completed on this system and there is considerable potential for further speleological research.
The system totals in excess of 4100m of passage and is 94m deep making it the third longest cave in Northern Ireland (7th longest in Ireland and 27th longest in the UK) and the third deepest cave in Northern Ireland (7th deepest in Ireland).
I - Hydrology
The water rising at Cascades is, at present, known to be derived from four main sources: sinks in the Brookfield-Gortmaconnell- Dooneen area, sinks in the streambed of the Owenbrean River, sinks east of Trien Hill (Goat Pot) and diffuse input over the system.
Notably, the Owenbrean Streambed Sinks and Goat Pot lie to the south of the Cuilcagh Dyke, indicating that there are hydrological breaches in this generally impermeable feature, possibly along N-S oriented faults.
II - Underground Karst
The Prod's Pot-Cascades System is an extensive dendritic vadose cave system draining an extensive area of northeast Cuilcagh Mountain. Streams sinking to the south and east of the cave system feed a number of tributary passages (Cascade Inlet, Formation Passage, Papist Passage) which meet in the Main Stream Passage. Prod's Pot is a vadose tributary inlet. The Main Stream Passage in Prod's Pot shows multiple phases of development and sediment infill, reflecting fluctuations in the hydrological regime in the system, possibly related to varying degrees of glaciation during the cave development.
A series of sumped sections of passage between Prod's and Cascades is probably related to "perching" of sumps on shale horizons within the mudbanks and/or intense fracturing and/or dolomitization associated with faulting.
The Main Stream Passage in Cascades Rising Cave shows similar features to that in Prod's Pot. The Sump Bypass Series is a largely abandoned stream passage which probably carried the main stream, prior to its capture by the Sump 7-Sump 8 passage. Creatures End is interpreted as a major vadose invasion inlet to this stream passage, which is now abandoned.
The Boulder Series is characterised by massive boulder breakdown, probably due to roof failure along thin impersistant shale bands within the carbonate mudbanks and large scale passage development at the Glencar - Dartry Limestone contact.
The Entrance Series, downstream from the Ducks to the Waterfall
Cascades Rising Cave: top of the Waterfalls, with floor of Glencar LImestone and roof of Dartry Limestone.
and the Letterbox
Cascades Rising Cave: Letterbox at the Glencar/Dartry Limestones contact.
is formed in the lowermost Dartry Limestone Formation and extensive breakdown here is, again, probably due to roof failure along thin impersistant shale bands within the carbonate mudbanks. The much smaller size of these passages may indicate recent capture of the stream, and that the larger passages of the Boulder Series were formed by a much larger stream which may have resurged at another site.
There is a notable topography associated with the Glencar-Dartry contact in the Waterfalls-Letterbox area, representing either a marked disconformity or lateral facies variation between the Glencar Limestone and the Dartry Limestone in this area. The Entrance Series from the Letterbox to the Entrance are formed in the upper beds of the Glencar Limestone and passage development has been restricted by the clastic content of these limestones. Breakdown is common due to the thin bedding and shales in the Glencar Limestone. The common black coating on the Glencar Limestones is due to Fe and Mn oxides which adhere to siliceous lithologies, but not to purer carbonates.
III - Surface Karst Surface karst in the Prod's Pot-Cascades area is predominantly composed of sinkholes, dolines and karren developed on a post- glacial topography, which reflects the original topography of the carbonate mudbanks of the Knockmore Limestone Member.
The Prod's Pot-Cascades Rising System is an extensive karst system with exceptionally well developed underground karst features in an excellent state of preservation. The system contains a number of unique karst geomorphological features and has a complex hydrology that is, at present, not fully understood. It is of significant geomorphological, hydrological and speleological interest and studies to date have been limited.

For site specific information see;
Key Site 339 - Prod's Pot Key Site 340 - Cascades Rising Key Site 341 - Gortmaconnell Pots Key Site 342 - Goat Pot Key Site 343 - Smokey Mountain Sink Key Site 344 - Harry Jacques Memorial Cavern Key Site 345 - Pelvis Pot Key Site 346 - Westminster Dig.
For information and reference lists on the systems and features of other karst areas within the Marlbank-Cuilcagh Mountain Region see;
Key Site 1153 - East Cuilcagh Key Site 1154 - Tullyhona, Brookfield and Trien Key Site 1156 - Marble Arch Karst Key Site 1157 - Western Marlbank.
No fauna has been previously recorded from this site and no collection was made in the course of the current programme. Colourless amphipods, probably Gammarus sp., were observed in static water just upstream of the Witheywindle inlet sump. It is possible that these may be a cavernicolous population.

Minerals:Calcite, Dolomite
Rocks:Limestone, Mudstone, Shale
Fossil List:
Structures:bedding, fault, joints, rift
Relations:No Data
Geomorph:breakdown, cave, cave pearls, clastic sediments, column, conulite, dendritic river cave, doline, drift, flowstone, gour pool, helictite, karren, pothole, sinkhole, speleothem, splattermite, stalactite, stalagmite, straw, sump, varve
Length:4100 m+Width:No dataHeight:No data
Depth:94 mArea:No data  
Approach:Not entered
Restrictions:Not entered
Planning:HISTORY OF EXPLORATION Prod's Pot was excavated and explored by the Reyfad Group in 1970. The various tributary sumps and passages beyond were dived by the CPG in 1971 and 1972. The complex and difficult downstream sumps were passed by the CDG in 1976 and the passages beyond these were explored downstream to the Cascades entrance series. Following this, the entrance to Cascades Rising Cave was excavated by the Reyfad Group later that year and the difficult entrance series was passed. The Prod's-Cascades through trip was finally completed by D. Woods and M. Campbell (Reyfad Group & CDG) in 1979.
Management:Internal Threats: The Prod's-Cascades System is largely an active, high energy river cave system, with only two arduous and constricted entrances. Much of the system is unlikely to suffer significant damage from cavers as cave sediments mainly consist of coarse clastic deposits and calcite deposits which are situated where accidental damage is unlikely. There are a number of short sections of fossil, or predominantly abandoned, cave where well developed calcite and clastic deposits could be damaged, but only one of these (preceding Creatures End in Cascades) is part of a main route through the system. (i) Cascades Rising Cave The entrance series of Cascades is constricted, difficult, almost devoid of calcite speleothems and prone to regular flooding (high energy). Damage by cavers is unlikely in this area. The succeeding Boulder Series is characterised by large passages with significant boulder breakdown. Mud deposits are common, although they are superficial and probably of little scientific value. Speleothems are present but are generally located where accidental damage is unlikely. The Main Stream Passage consists of large high energy active river passage with large sediment banks in places
Cascades Rising Cave: glacial sediments in Mudbank Chamber.
and abundant speleothems on the passage walls and roof. The sediment banks and speleothems are not positioned in the main routes taken by cavers within the passage and are thus unlikely to suffer accidental damage. Within the Sump Bypass Series the initial passages are sand floored rifts with no speleothems. There is little of significance in this area to be damaged. The 40m of passage immediately preceding Creatures End is a low energy area and has a significant number of mud and calcite formations on the floor of the passage. These are prone to damage by careless progress. There is a well trodden path in this area which avoids the formations, although heavy traffic could lead to significant degradation of the deposits. Due to the strenuous nature of the cave preceding this area, many cavers turn back prior to reaching this point. There is little potential for damage to any features in the cave in the passage upstream of Creatures End. (ii) Prod's Pot The entrance pot is a high energy active stream sink pothole and damage is unlikely in this area. 8mm bolts have been placed in a number of sites to provide belays for equipment in the pot. No further placements are necessary and the existing 8mm bolts are to be replaced by permanent 'Eco- hangers'. The Main Stream Passage and Cascades Inlet Passage are high energy stream passages and all speleothems are in locations where accidental damage is unlikely. Formation Passage contains many calcite speleothems although the best developed of these are beyond the first sump and diving is required to reach this area. The passage to the west of the sump is also well decorated, but as this passage closes at the end, it is unlikely to receive many visits. Papist Passage is a large stream inlet which is unlikely to be seriously degraded by cavers.
External Threats: Much of the land overlying the Prod's-Cascades System consists of upland pasture and peat bogs. The peatland in Brookfield and Gortmaconnell townlands, immediately overlying the system, is unexploited by cutting and the upland pasture is largely unimproved (although a large number of dolines in Leefa Td. were infilled in the early 1970's). At present there are a number of activities in the area which represent a potential threat to the cave system. 1:- Dumping of rubbish and animals in Dooneen Rattling Hole has been ongoing for some time. Dumping of household rubbish has decreased, although disposal of fallen animals has increased in recent years. 2:- Extensive peat extraction and associated drainage improvements (gripping) in the Owenbrean River catchment may result in increased sediment input to the system. 3:- Spreading of human sewerage effluent has taken place on the land overlying the cave system and its catchment. 4:- Engineering work has been undertaken by the management of Marble Arch Show Caves at the stream sink in the bed of the Owenbrean River which has been traced to Cascades Rising. This was undertaken in an attempt to decrease the amount of water sinking at Pollasumera (and increase the amount of water in the Prod's-Cascades streamway). This work is unlikely to have affected water levels as the conduit from the Owenbrean River sink is probably at maximum flow in most water conditions. If the excavation had been successful however, it would have seriously affected the flow regimes in both Prod's-Cascades and along the underground course of the Owenbrean River in the Marble Arch System. The consequences of the resultant increased flood pulses in the long, wet and constricted entrance series of Cascades, were caving parties present at the time, could be serious. 5:- Gortmaconnell Scenic Viewpoint has been recently constructed including a car park. Some surface karren has been damaged, although this damage is minor and will ameliorate with age. 6:- The DOE (NI) Water Service currently abstract 1.2-1.6 million litres of water per day from Cascades. This is projected to continue until June 1998 when the new plant at Killyhevlin comes on stream. This activity does not affect the Prod's-Cascades system but, with water velocities of up to 300m/hr within the cave system, has obvious implications for pollution from dumping within the Cascades catchment.
Threats:Accidental damage by cavers; dumping; peat extraction; spreading of human sewerage effluent; engineering, construction work.
Uses:Not entered
Potential:Future exploration in the Prod's-Cascades system is likely to centre on attempts to discover the links between the known cave system and the various sinks in the Brookfield area, Owenbrean River and Goat Pot. There is a possible connection between Cascades and Marble Arch.
Educ. Level:Not entered


The following areas have been marked on OSNI 1:10,000 sheet 243; / / PC 1. Area immediately overlying the known cave passages in the Prod's Pot- / Cascades Rising Cave System and Gortmaconnell Pots. / PC 2. Postulated karst catchment for the Prod's Pot-Cascades Rising Cave / System in the Dooneen and Brookfield areas. / PC 3. Owenbrean River Sink feeding the Prod's Pot-Cascades Rising Cave System / and Owenbrean River episodic stream.

Map No:None entered
Rec Type ESCR report Recorder:  
Enterer: E M Porter
Updates: 4 Aug 2004 / 17 Jul 2004 / 28 APR 97 / 07 MAR 97 / 05 MAR 97 / 26 FEB 97 / 25 FEB 97 / 24 FEB 97 / 21 FEB 97
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