THE EXPLORATION OF MONTAGU SOUTH PASSAGE LANCASTER HOLE

See passage description

From RRCPC 5

Jim Newton
 
The summer Bank Holiday of 1969 saw a number of the Red Rose at Bull Pot Farm intent on keeping Duncan Baldwin to his promise of a new passage joining Bull Pot of The Witches with Lancaster Hole.  After two days of excitement and then finally disappointment, we decided to go and prospect down Lancaster Hole.
 
I had an idea that digging in Skittle Alley above the pitch might prove profitable, but on seeing the upstream sump, we decided to bale this instead.   If I had read the reports of previous attempts, I no doubt would not have bothered as it seems that many other clubs have attacked this sump and failed.   However, with Roger Bowmer and Ian Carruthers wallowing in the water, which soon turned to liquid mud, the level dropped and soon an air space appeared through which blew a strong draught.  After about another hour Ian(Eccles) reported that it looked possible to get through.  We shoved Pete Llewellyn through the twelve foot crawl and he then dug away a sandbank which was retaining more water in a precarious position above the sump on the far side.   This raised the Bump level once more and we recommenced baling.   Roger then splashed through to join Pete.
 
They found a way ahead through a small crawl into a passage twenty to thirty feet high, and two to four feet wide, which they followed for about three hundred feet and then returned with the report that it closed in.   After further baling, the whole party, including several brave lads in woollens went through to have a look.   I was feeling somewhat disappointed at the apparent end of the passage, when I thought I heard water dripping.   After climbing as far as possible up the final mud slope, it appeared that there was a further passage entering about twenty feet up the wall.   We were determined to push it further.
 
On the following Saturday with the kind permission of the club who had booked Lancaster Hole for that day, five members gathered at the sump with more buckets and scaling poles.   Only one and a half hours baling was needed this time as the weather had been dry.   We soon started assembling the pole at the previous limit of exploration.   This took some time as everything was full of thick “goo”.   As it was resting on mud we sent up our lightest member, Duncan Baldwin.  We then watched the pole sink six inches deeper in the mud for each step he took up the ladder.  We overcame this problem by placing the pole on a spade, and we were soon deafened by Duncan screaming madly “It's huge! It's huge!”.  He soon calmed down and requested another ladder to descend into a chamber which opened up before him.  When he arrived on the floor of this chamber, his light was visible through a six inch hole in the bottom of the wall which separated us, and up which he had just scaled.  We were soon shaking hands with him through this hole.   We joined Duncan (the long way round) and galloped on up the sole passage leading on.   This rose quickly and after about one hundred feet one had to crawl.   There were only a few formations, but these were virgin white against the grey clay of the passage floor. We slid through a short “flattener” and came into a very wide bedding plane, which we pushed as far as possible until it became too low. The floor however, appeared reasonably soft under a film of calcite, so we decided to return again equipped for digging.
 
The following weekend brought out all the “ghosts” who traditionally appear on these occasions, and twenty members ploughed through the Aquamud Sump as it was now called.  One suggestion was that perhaps all of these bodies would take out all the mud on their clothing, but there was much too much mud.   A couple of avens were scaled, and a few "ferrets" attacked the crawl at two points following the strong draught which emerged.  Three thin ferrets, Pete Llewellyn, Andrew Walsh and our President, pushed straight ahead, where one could see for about sixty feet, whilst the well built ferrets, Eccles, Bev Stevens and myself, hammered away at a crack on the right hand wall.  It was very cramped and cold in this crawl, and after about an hour, enthusiasm waned.  The centre party had managed about another thirty feet.  We retired beaten on this occasion.   Aquamud Sump had almost filled up, due to everybody sliding down into it and taking more sand and mud with them.  That night in the pub, the Aquamud men were recognisable by having one mud filled ear.
 
The following week, two of our members from Scotland decided to show the Sassenachs a thing or two.   Frank McVey pushed the crawl for a further hundred feet, reporting that it still went on after this.  He returned however, as Mike Abrams was out of earshot.   It was thought that the passage swings towards West Montagu Passage, but when this latter passage was tested with smoke, no emergent draught comparable with the one entering Montagu South Passage was found, nor did any smoke appear in Montagu South Passage.  The possibility of an eventual connection with Waterfall Passage is being worked on.
 

TOPOGRAPHICAL ACCOUNT MONTAGU SOUTH PASSAGE.


Duncan Baldwin.
 
A topographical account of Montagu South Passage cannot be complete without a descriptive note on its continuation, Skittle Alley. (Eyre 1967).
 
It has long been assumed that Skittle Alley corresponds directly to passages extending south from the Graveyard region.. A detailed comparative study between the Skittle Alley and Montagu South Passages, and the passages associated with the Graveyard has revealed significant differences in both structure and origin.
 
Skittle Alley lies in the southernmost extremities of Lancaster Hole, and is distinguished as being the furthest point negotiable from the Easegill Caverns in the general direction of the resurgences.     To reach Skittle Alley the way exits from the Graveyard into the partially infilled area known as Stump Cavern.  Forward, a low indefinite bedding plane terminates in several holes between jumbled blocks.   From below a constricted fissure descends amongst further breakdown to join a small tributary emerging from the right.   A more spacious passage then leads onward to where a conspicuous domed mudbank marks the junction with the Skittle Alley Passage.   Viewed from the junction an arched tunnel tapers gradually upwards contracting to solution hollows of various shapes. Beneath, a small trickle runs sluggishly in a shallow entrenchment impeded by the muddy remnants of past infill.   Downstream, the floor descends rapidly as the walls continually rise to display a high imposing canyon form, similar in design to the closing stages of the Master Cave.   A number of fallen blocks now span the floorway soon to terminate abruptly in a deep sombre canal, probed abortively by divers to a depth of 20'.   Beyond, stretches an exposed traverse to a delicately poised boulder scree, the true 'Skittle Alley', a former inlet, since choked by glaciation and left obscurely abandoned.
 
Upstream of the junction, the rift-like form dips to an ovaled phreatic tunnel ascending steadily as its size decreases.   Shortly an enlargement is reached. Here, recessed to the left wall and slightly above floor level an inconsequently placed shaft opening drops vertically for 50’ to a gravelled bottom, sealed impenetrably by consolidated detritus. Situated above the shaft at roof height, a silted phreatic tube extends a short distance before becoming choked.   Along the roof are some noteworthy solution pockets, indicative of a phreatic conveyance horizon prior to the shaft's existence.  The actual purpose and formation of this shaft remains still a mystery.   Outwards from the chamber, the main passage makes a lateral twist and an inconvenient collection of curtains provides an extra intricacy.   Immediately, the roof lowers and a shallow pool deepens to swallow the passage.
 
This was the limit of exploration until October, 1969. When drained, a deplorable mud wallow, the Aquamud Sump, discloses the beginning of Montagu South Passage.   Once through the muddy section the roof lifts to retain its distinct phreatic character.  A sparse covering of sand now overlies deeper muds which obscure most of the passage.  Ahead, an awkward crawl by-passes the water and drops into the resumption beyond.   The passage now unexpectedly heightens depicting again an avened phreatic rift, containing inumerable unmarked bores and pockets. The noticeable intersection of a master joint produces henceforward an elongated rift 30’ high by 2' to 3' wide.   The straight linear shape however is soon offset as a low arch is encountered, although this risesinstantly into a similar continuation.   Occasional static deposits are prominent on the walls here, denoting bygone stagnated sections formed when the arch was blocked.   The walls throughout are stained and darkened by the clinging coating of mud and ascend into joint interstices solutioned into small symetrical hollows.   Widening slightly, the way remains otherwise unaltered until a high ampitheatre of mud bars the way.   An easy scramble leads above the blockage to an apparent dead-end in a constricted fissure which serves to emit a small trickle.   The way on is gained by a 20' scale up the right wall onto a wide and lofty chamber.  This ledge is about 6' in width and represents the top of a rock partition, (The Partition), which tapers to a bare few inches width at its base.   A 20' pitch leads down besides a precariously balanced slab to land on the chamber floor.
 
The chamber, (Newton Hall) is 40' in diameter and carved roughly circular at its base.  Rising above, a high aven discharges a trickle falling in fine spray onto a flat gravelled floor.  The water then enters the fissure to reappear instantaneously on the opposite wall of The Partition.   The chamber walls present a turbulantly fashioned vadose sequence showing a diversity of cockling, evidence of an accelerated flow of appreciable volume.   The stream obviously ceasing as the marked change to phreatic occurred.   A selection of transitional cockling can be seen above The Partition, indicating the consequent development as each successive phase contacted the master joint.  There appears no rational explanation why The Partition has not sustained simultanious dissection and erosion.
 
A 20' high rectangular passage leads outwards from the chamber, resemblant of many streamways in Easegill Caverns.   A mud slope marked by countless drips and now a few footprints, inclines upwards to a jammed block, which having detached itself from the roof stands to hold dammed, a mass of solidified muds.  A broad bedding plane roof extends above forming a typical 'T' cross-section sloping inwards to the incised centre.  Within a short distance deepening fill masks the floor trench forcing one into the widening roof above.  A profusion of phreatic shapes now dominate the remaining passage characterising a sudden change of form. The width now increasing to over 15’ thus allows access on the right to numerous small avens and paralleled solution pockets, some containing fissured inlets blocked by surface debris.   Running alongside the latter, a low crawl, clay floored and sparingly decorated with straws, shows evidence of recent periodical stream-wash.  The ways then gradually merge into a low arched bedding tunnel.   The roof ahead consists of a series of minor undulations, the larger hollows creating small chambers, again some possessing narrow fissures ending in fill.   Shortly, a narrow rib-like archway lifts into a broad bedding chamber, adorned gracefully with many long slender straws, some forming miniature columns, others detatched and speared upright into the soft mud covering beneath.   The intermitant trickle has in places removed the top mud layer to expose a thin deposit of calcite, concealing deeper fill to an unknown depth.   An extremely low but forcible crawl gives respite after what seems to be quite a distance.   Here, unfortunately, the way terminates as yet.   A small fissure in the floor however, carries a small trickle to a secret destination; the overflow of which has probably caused the invasion along the passage.  An aven extending upwards seems to expel a slight draught. This and the crawl, are still being worked on.
 
References for further reading.
 
Eyre J. C.R.G. Transactions. Vol. 9. No.2. 1967. Lancaster Hole and The Easegill Caverns.
 
Descent No.7. & No.8. 1969.
R.R.C.P.C. Newsletters. Frankland J.C  Vol.6. No.4. 1969
                                        Newton J.        Vol.6. No.5. 1969.
 

THE ORIGIN AND DEVELOPMENT OF MONTAGU SOUTH PASSAGE IN RELATIONSHIP TO LANCASTER HOLE
 
Duncan Baldwin
 
Since the initial exploration of Montagu South Passage, much detailed examination has been completed.  Owing to absence of extensive infill at significant points, a higher grade survey was easily carried out.   This, coupled with observations on its wide morphological range, has provided information to enable some aged discrepancies concerning the subsequent development of Lancaster Hole to be elucidated.
 
Geological Outline.   Montagu South Passage combining Skittle Alley forms an outermost ‘fossil route' bounding the inner framework of The Graveyard and the Bridge Hall complex.  The former has evidently evolved in two sets of master joints extending N-S and N-E from the synclinal fault zone located as the dry valley defined between the Bull Pot watershed and Leek Beck Risings.  Throughout Montagu South and environs the bedding lies almost horizontal and consists generally of massive bedding interrupted only by thin bands of shale.   The dip is slight and remains little more than where the strata is uniform in the locality discussed.   The tendency of the dip is N-W and produces a series of gradual anticlines which have a measured effect on the whole. Lithologically, the strata is consistent, and is seen to alter only at the outer margin adjacent to the fault area.
 
Speleogenic Outline.  Three distinct passage forms exist in Montagu South, each having formed simultaneously with its neighbouring part.  The furthest point has been shown to come within a short distance of the terminal section in Montagu West Passage;  (The excavated part), testimony to the obvious counterpart.   The extremities of Montagu South display much phreatic sculpture, exhibiting many fine solutional hollows equal to those found along Montagu West.  Progressing in a downstream direction, the undulating roof indicates a transition to semi-vadose movement.   The numerous fissured avens surrounding show signs of past mixed waters from above, or, alternatively, a buried confluence near. The presumed connection is to The Colonnades Passage in close proximity to the left.
 
As Montagu South nears Newton Hall the releasement from submergence produces the start of the floor trench and the unfolding planed roof above.  The phreatic forms now become superseded by an incised vadose streamway preserving clearly a mixture of cockling extending to the roof.
 
Newton Hall
This large conicle shaped chamber previously described, shows with surprising clarity the final erratic change to phreatic.   The route onward now becomes strongly joint influenced as one progresses to Skittle Alley, where the submergence continues as present day formation.
 
Origin and Development.  
Montagu South, as stated, had three active forms; two outer phreatic sections enclosing an intermediate vadose streamway.   This may have originated from Montagu West Passage and probably with a similar foundation existing to the Colonnades Passage prior to its rejuvenation into Bridge Hall.   The single or combined waters have then produced the vadose section and gravitationally bisected the secondary phreatic section already in an advanced state of solutioning.   Evidence for this pre-existing part is found in the roof of the abandoned vadose section.  The wholly vadose sequence noted here has borne no marked phreatic form, thus isolating the two outer solutioned conveyance areas. The respective phreatic rift following contains no vadose signs either in initiation or later transformation to conveyance.   Secondly, an inspection of their volume relation and solution rate suggests a considerable duration gap.   This significant difference in age depicts a proportionally uniform phreatic-vadose development into Newton Hall; at this point entering an inconsistent rift to vary greatly in area and forming relatively slow over a wide time expanse.   Displacement along the latter phreatic rift has left little recognisable directional cockling, except the steady incline into Skittle Alley.
 
Skittle Alley appears vast in area, although strangely deceptive.   By an uncanny artesian action, the main sump is known to rise and fall suddenly in flood times in excess of 20’.   This fluctuation in level may be due to hydrostatic pressure from Lost John's System, or from Lower Easegill Pot.   Alternatively, the Master Cave could have measured pulsing effects on the whole.   Diving in this sump has been unsuccessful due to there being no obvious exit once below the water line, the rift seemingly diminishing into a constricted fissure.
 
To summarise, it would appear that these phreatic rifts have originated as solutioned tectonic cavities ceded to cave form during the course of invasion.   Firstly, by deep hydrolic pressure forced upward to later phreatic directional action and subsequent conveyance modification thereafter.   Verification of development on these lines is seen at the noted constriction points, i.e. The Aqua Mud Sump and The Archway. Here, large cavities are linked by small tunnel forms, showing at these points cockling.   This may be the result of pressurised waters connecting the existing tectonic parts of the aligned fracture.
 
The following development stages can be recognised within Montagu South and West Passages.   This is primarily a succession table, and not a time relationship index.
 
Stage 1.
Inter-carboniferous faulting causing cavitation centered on the Dent Fault area of the locality.
Stage 2.
Pre-cavernous solutioning by intrusive waters.
 
Stage 3.
Supersedence by cavernous development, thus:-
(a)        Phreatic conveyance forming Montagu West and South and related counterparts in Bull Pot of the Witches in conjunction with the 790'-800' speleogenic horizon.
(b)        Vadose action producing Montagu South Streamway, Bill Taylor's Passage and Montagu East.
(c)        Vadose rejuvenation resulting in the abandonment of Montagu South, West and East, and the formation of Waterfall and Wilf Taylor's Passages and numerous others.
 
Correlation to Lancaster Hole.
 The result of the findings in Montagu South, tends to discount the past existance of several water tables debouching at various levels. The marked speleogenic horizon at approximately 790' ASL in Lancaster Hole has, in its duration, formed a lower stage, hence the abandoned streamway in Montagu South.
 
The latter vadose area has conducted a negligible volume of water compared to Montagu East, had this formed Montagu West as previously suggested.   Montagu West, as observation shows, has taken the quota flowing Northwards along Bill Taylor's Passage from the foot of Lancaster Hole shaft, where a comparable passage lies heavily choked.   The former route of this flow was through the Colonnades Passage, thence onward to Montagu South to enter above the abandoned streamway.   Rejuvenation at Bridge Hall resulted in Bill Taylor's Passage.   Bridge Hall is so transmogrified by invasion and bisection, that it is difficult to establish this positively.
 
The surface engulfment point is disputable, probably an archaic Easegill flowing South of Lancaster Hole entrance may be responsible.  The ultimate destination was, as clearly denoted by cockling, Montagu West, then to join water being transmitted under hydrostatic pressure Southwards from Wilf Taylor's sump area.
 
Indicative by flow markings, semi-phreatic conditions persisted along Montagu West, gradually changing to phreatic upon nearing the 'excavated section' at the junction North.   The united waters have then been conveyed along the 'excavated section' to be further joined by another phreatic tunnel.   As only a relatively small portion of this is visible above infill, the true dimensions cannot be measured accurately. ENridently, this has also conveyed along this horizon from the many radiating levels within Bull Pot of the Witches, explored as far as 750' North of this point.   The combined waters have then, by displacement, gone South, thereby creating Montagu South.  (See diagrams).
 
The question then remains; what was the destination of Easegill waters as this horizon must have been developing during this period? The solution lies in the bounds of Fall Pot.   Here, a hall of vast ramifications has previously been regarded as a distinct collapse of Montagu East Passage.   The presence of an indefinite counterpart at this point has added to the misconception.   If the blocks that litter the floor were removed, the roof of the present Master Cave would be exposed.   The sudden increase of the dimensions of the Master Cave at this point clearly illustrate the apparent connection to the obscured area of Fall Pot.   Ample height, coupled with sufficient passage area equates the closing stages of the Master Cave with the horizon from Easegill Caverns.
 
The Graveyard curiously isolated in its position, seems to have no obvious continuance elsewhere in Lancaster Hole.  The majority of its form is concealed behind infill and it guards closely its secret.   Due to the few bisectors radiating from its bounds, some idea has been gained of its form.  Clearly, the association to Montagu South is via the entry route, where an active passage has invaded the dead area of Skittle Alley. It is probable that the bulk of The Graveyard connects to Sand Caverns.
 
 
Correlation to Surface and Leck Fell Caverns.
 The flow indication depicts a Southerly flow from Sand Caverns in the direction of Leck Fell.   With the exception of several shallow pots this area is known to be void of any dry system of Lancaster Hole's magnitude.   The confirmation of this Southernly flow, prior to the existence of Leck Beck Head, opens a wide dimension of potential.   Dry levels intersected by the gill at Easegill Kirks stand to support this. Recent excavations by The Red Rose Cave and Pothole Club of these has shown them to be large, and as expected, quite old.   A former valley horizon running approximately 90' above the present course of Leck Beck can be correlated to the underground development at this height.   A debouching point at this level is probable, the actual location of which is unknown. Judging from present information, it is feasible that Montagu South has been part of Lower Easegill Pot, transmitting syphonic pressuredwater through the large phreatic tunnel within, and thence to Leck Fell.
 
It is acceptable that this is the source of Duke Street, which most likely resurged in Kingsdale at a level higher than that of Leek Beck Head.  Keld Head may have been the continual dischargement point for this area of Lancaster Hole at such times before the deepening of the Leck Valley.