Saturday, 29 June 2013

The Limestone Benches of Ingleborough

Yorkshire's most famous mountain has a fascinating geology.  The actual 'cone' of Ingleborough, seen in the background, is made up of a great 'sandwich' of rocks known as the Yoredale Series (Yoredale being an old name for Wensleydale where these 'sandwiches' are prominent).  The actual Great Scar Limestone, seen in the foreground, and for which Ingleborough is internationally famous, was formed in a clear tropical sea about 340 million years ago from the remains of shelly creatures and corals.  Changes in sea levels caused the 'Yoredales' to form on top, made up of alternating bands of limestone, sandstones and mudstones.  The thin limestone layers of the Yoredales were formed from living remains when the water was very shallow and muddy.  When land was exposed altogether layers of sandstone were laid down by rivers washing in sands and gravels, and when conditions allowed plants to flourish, thin seams of coal were also formed.  

All the water flowing off these steep Yoredale slopes eventually meets the 600 feet thick layer of Great Scar Limestone and sinks into it at the earliest opportunity - finding a handy joint or bedding plane and slowly dissolving the rock into a cave passage or pothole.  This is Great Douk Cave, formed on a fault.  The water enters the limestone through a pavement half a mile to the east and wanders through an exciting cave passage before emerging here in this huge collapse crater.  The water has no sooner emerged from the cave than it sinks once more into the limestone floor!

Emerging here at Great Douk Cave, the stream can be seen to have cut out a major joint beneath a bedding plane, leaving a characterisitc 'T' or 'Y' shaped entrance.  It's quite easy to enter for tall people as nature has kindly provided a step in the waterfall.  Some people avoid a soaking by crawling along the ledge at top right, actually easier than it looks on the photograph.  About 800 metres of superb walking size cave passage can be explored, with cascades and formations, before a crawl in water leads out onto the moor.  I'll bring you back for a full exploration before very long.

The base of the crater containing Great Douk is choked with rubble.  It is highly likely that this was once a huge cave chamber that has collapsed, and that the waterfall we see today once cascaded into pitch darkness.

A view from the northern slope of the ravine shows the ledge up on the right.  Great care should be taken at the entrance where algae makes the rock very slippery - and the cave is very active, so should only be entered in calm weather.  In times of heavy rain it can be impossible to get near! In many ways this is a miniature version of Weathercote Cave on the opposite side of the dale - an underground stream crashing into daylight through a 'window' in the limestone, before once again disappearing into darkness.

This is the boulder-strewn floor of the crater of Great Douk - with the 'dig' of Great Douk Pot visible in the far right corner, where cavers have been tracing the course of the water as it heads through the limestone to emerge at the basement rocks in the valley bottom.

The Great Scar Limestone pavements of Scar Close, beyond Great Douk, have been protected from grazing sheep for years.  They are therefore thought to resemble such a limestone environment as it might have looked well before farming was thought of!  There wasn't a great deal of light today - but the beauty was undeniable.

This smooth plateau of Great Scar limestone was once covered by the 'sandwich' layers of the Yoredale series, as can be seen by the lower slopes of Whernside in the background - remnants of that once massive layer.  Glaciers in successive ice ages have effectively 'bulldozed' these layers away and scraped clean these magnificent pavements of white limestone.  The ice moved from right to left across the picture, and at its height would have covered even the slopes seen in the background.

The classic Yoredale slopes of Whernside with the pavements of Scar Close contrasting superbly.  This picture gives some indication of the height and width of the glacier that flowed down Chapel-le-Dale.

As these pavements are quite isolated from the Craven Faults, they tend to have massive irregular clints of unbroken limestone - unlike the latticed 'bar of chocolate' clints and grykes of Malham Cove, for example, which lie very close to the Mid Craven Fault.  Nevertheless, the grykes here are spectacular and are home to a variety of rare plants.  

A sandstone 'erratic' which was plucked from the valley sides higher up the dale and dumped here when the ice melted around 12,000 years ago.  

This weathered limestone boulder has been dropped by the glacier at an angle on a smaller piece of limestone resting on a clint.  The weather, wind and driving rain over thousands of years have reduced this supporting stone to a tiny pedestal.  This is a superb feature of the Scar Close pavements.  Beyond can be seen the Yoredale slopes of Southerscales Fell, the middle section of the Ingleborough massif.

Like a natural altar, the boulder has stood here for at least 12,000 years.  Notice how many of the surrounding grykes are filled in with glacial till - allowing grasses to grow - at least without our woolly friends around.

Classic grooving caused by water running off the elongated clint in the direction of the camera.

Looking south-west across the width of Chapel-le-Dale from the edge of Scar Close.  The Yoredale foothills of Whernside are on the extreme right, with Gragareth peeping behind.  Just above centre are the massive pavements of Scales Moor (see earlier post), scraped clean by the glacier, whose route can be seen from right to left across the picture.  The field in the foregound shows pavements peeping through a very thin layer of till, (clay, pebbles and boulders) deposited by the glacier.

The weathered clints on the extreme edge of the Scar Close Nature reserve - looking north towards Ribblehead.  A thin layer of till covers the pavements to the left.

Ingleborough broods over the lush landscape of Scar Close Nature Reserve.

Another wonderful stretch of Great Scar Limestone punctuated by rich vegetation.

A perfect combination:  Globeflowers, white limestone, and Yorkshire's greatest mountain.

Look closely at this isolated hole in the limestone and a very fine crack can be seen either side- the original weakness in the rock which rainwater and run-off has exploited to full advantage in hollowing a way through.

The Scar Close Pineapple?  Not many boulders dropped by the glaciers are free from sheep attack, so when they are - they tend to produce something quite bizarre.  

Looking the other way - showing the rich variety of wild flowers, grasses and mosses around the 'pineapple'.

Carpets of beautiful white cotton grass dominate the lowest Yoredale slopes before they meet the Great Scar Limestone at Scar Close.  That's Whernside rising beyond.

At Keld Bank, near Scar Close, minor faults reveal the pinkish-grey limestone of the lower beds of the Yoredale series; a very different limestone to the Great Scar both in looks and composition.  A stream runs down off Southerscales Fell and has an interesting journey from this point onwards ...

The lowest limestone beds of the Yoredale series were, if you recall, formed in very shallow muddy waters when sea levels fell, and doesn't it show here at Keld Bank - looking at this thinly-bedded, muddy-looking rock?  The stream has managed to cut through it to a shale bed beneath ...

But not for long!  It has soon encountered the limestone again ... and managed to vanish in its own bed, here at Keld Bank Sink. It quite simply disappears through a slot.

The stream used to sink further down before it found that 'new' route.  Here is its old course, still active in times of flood.

Exposed clay and boulders here at Keld Bank show the layer of glacial till that has been plastered over the underlying rocks.

The old route of the stream curved its way(top of photograph) to this larger slot into the Great Scar Limestone - and once a stream hits the Great Scar - the inevitable cave begins to form.

A 'manhole' into the streamway follows Keld Bank Sink through a wonderful cave passage: a hands and knees crawl to eventual walking and two lovely underground waterfalls - formed as the stream makes its way through the Great Scar Limestone.  

I didn't fancy crawling in without caving gear - but here's the passage from the manhole to the alternative entrance - with scalloped walls.  I'll be back before long.

Park in the second lay-by on the left just above the Hill Inn on the B6255. Scar Close is a National Nature Reserve requiring a permit to enter.  Write to the senior reserve manager, Colin Newlands, at Colt Park Barn or google it and telephone for permission.  Great Douk is the tree-filled crater looking like a small island on the image just off the south west tip of the reserve  (just below left centre).  A wall runs north east along the south eastern boundary of the reserve - clearly visible on the image.  Where it meets the first wall coming down off Southerscales Fell, just above the centre of the image - a careful search will reveal Keld Bank Sink.  Take your time and savour this unique place.

Stephen x

Friday, 28 June 2013

Easegill Force
Ingleton's Hidden Cascade

Ingleton is famous for its waterfalls, but there are several in the area that aren't as well known - for various reasons: mostly due to difficult access or a remote location, requiring that extra degree of effort to reach.  One such example is Easegill Force (SD709728) - not be confused with Easegill above Cowan Bridge.  In this hidden glen just off the old road from Clapham to Ingleton, some of the finest river and gorge scenery in the Three Peaks can be found.  This was an area much frequented by 19th century writers and explorers ... and no wonder.

The great fracture known as the North Craven Fault cuts left to right across the fields leading up to the wooded glen of Jenkin Beck, where the waterfall is situated.  The underlying rocks in the foreground, on the south side of this fault, have been 'downthrown' about 600 feet from their original position, so that, effectively, the same plane of Great Scar limestone that can be seen on the upper skyline at Crina Bottom, now lies buried far below these fields.  A layer of glacial drift (debris left by the ice) now blankets these valley sides.  A massive amount of Great Scar limestone has been eroded or 'trimmed' away north of the fault to leave the 'wall' or plateau as a distinct block on the skyline.  A combination of uplifting in the area north of the fault, and intense erosion by rivers and ice has, in places, uncovered basement rocks 500 million years old!

Entering the glen formed by Jenkin Beck, which has cut deep into the lower reaches of the limestone plateau.  

An attractive cavern is passed on the right bank of the glen as we head into the depths of the gorge.

The glen itself is a luxurious growth of wild garlic, mosses, ivy and ferns - all typical of the limestone dales.

Small cascades are numerous and contrast with the rich green foliage.

Some cascades have to be seen moving to be fully appreciated.  This one is encrusted with mosses.

There are no paths in the glen and all is, seemingly, natural chaos: fallen trees, boulders and slippery slopes of vegetation.  An explorer needs to take care ...

Looking back towards the entrance of the glen, with Jenkin Beck making its way out to the sunshine.

Crescent-shaped limestone cliffs such as this show where water has previously cascaded into the glen: most probably meltwater torrents at the end of the last ice age.

Excitement mounts as the glen swings at an acute angle to the right, and the cliffs grow in grandeur.

First impressions on film, from the encircling cliffs to Easegill Force in all its splendour.

Easegill Force sees Jenkin Beck exploiting a weakness in the limestone and gradually enlarging a massive natural arch, still marked on ordnance survey maps.  An impressive 'bar' of limestone has been left, spanning the fall; a feature that is unique in the area.

Seen from the east side of the glen, the full majesty of this beautiful waterfall can be better appreciated.

Witness the spectacle, before we climb the east slope for a view from above.

I climbed up the east slope and, with great care, managed to get a stunning view down the fall and under the natural arch - itself a 'rock garden' for a multitude of plants.

The delicate cascade, like the tail of a mare, curves gracefully as a ribbon of white water beneath the arch.

My final view was from the east side.  In dry conditions, enthusiastic explorers can edge their way down onto the 'bar' of rock itself.  I let discretion be the better part of valour - and lived to see another adventure!

There are no public paths to Easegill Force.  Enquire for permission at Fell End Farm (extreme top left) which is just outside Ingleton on the left of the Ingleton to Clapham Old Road.  To reach the force, I always take the second gate on the left after Yarlsber, following the wall eastwards immediately from the 'old' in 'Clapham Old Road'.  At the junction with the next field and through a gate, turn 90 degrees (north) along the wall towards the obvious tree-lined glen in the photograph, dropping down a steep grassy slope to the lower reaches of Jenkin Beck.  After that, it's a slippery scramble up the glen to the force itself.  The obvious earthwork to the right  of the gorge has never been reliably dated. We will return to explore it on a later adventure.

Stephen x

Sunday, 23 June 2013

A Trow Gill Skeleton: The Unsolved Mystery of Body Pot

The Unsolved Mystery of Body Pot

Photograph by kind permission of John Cordingley

Hidden on a ridge high above Clapham Bottoms is an insignificant looking shakehole which, since 1947, has been christened 'Body Pot.'  The story surrounding it is one of the macabre mysteries of the Yorkshire Dales and is unlikely ever to be solved.  

Body Pot is one of a series of small potholes found on Clapham Bottoms, an undulating area of limestone between the famous gorge of Trow Gill and the wild moorland of the 'Allotment' on the south eastern slopes of Ingleborough.  Close to Ingleborough Cave, this steep path heads out of the meltwater valley of Clapdale and takes the explorer up to Long Lane, an alternative high level route up from Clapham.  Once the stile is reached (top of picture) the route lies to the left, following the wall up to higher ground, where few people, except farmers and cavers, ever tread.

Clapdale Farm, formerly the fortified manor house of Clapdale Castle, the seat of John de Clapham in the 14th century: a supporter of the Earl of Warwick.  This view is from the Long Lane route to Clapham Bottoms, accessed through tunnels in Clapham village created by the Farrer family.  The farm ingeniously draws water from the beck far below using a 'ram pump' which forces the water up the steep hillside.

Ingleborough Cave, viewed from the vantage point of Long Lane.  Once known as Clapdale Great Cave, it was made accessible in 1837 when James Farrer ordered a stalagmite barrier to be removed, releasing an underground lake.  Only after 146 years of trying was the link to Gaping Gill finally confirmed when, in 1983, divers made the connection.

Looking back from the steep path linking Long Lane to the route through Clapdale.  Trow Gill and Gaping Gill lie straight on, while the trees to the right screen another route to Clapham Bottoms.  This attractive dry valley was widened  by meltwater at the end of the last glaciation.  Hundreds of feet below the grassy slopes in the centre of the image lie the far reaches of the Gaping Gill system.

Small scars and boulders of weathered Great Scar Limestone reveal themselves as the rough path winds its way up through Clapham Bottoms.

Looking back down the appropriately named Long Lane towards Clapham. The limestone benches of Thwaite Scars, up on the left, together with the width of the valley, merely indicate the sheer dimensions of the glacier that flowed down here during the last ice age.  

During the ice age, the great shaft of Gaping Gill was plugged by ice and glacial debris.  Towards the end of the glaciation, as the ice began to thaw, torrents of meltwater couldn't access Gaping Gill and so famously carved out Trow Gill - as seen here, over thousands of years: the classic example of a meltwater gorge.  Today it has been left dry with the water once again finding its way through the Gaping Gill cave system.

Looking along Clapham Bottoms, where dolines (subsidence or solution depressions) give some indication of the activity deep beneath the surface.  The suspected 'Clapham Bottoms Master Cave', despite years of exploration has, as yet, not been discovered.

Bare, exposed rock and emerald green turf are characteristic of limestone country.

Extensive view towards Thwaite Scars on the left and the woodlands of Trow Gill on the right, with the Bowland Fells beyond - their darkness contrasting with the limestone landscape.

Dry valley in the upper reaches of Clapham Bottoms - probably representing a former post-glacial stream channel that has since found a new route underground.  There are many such features in the area.

Scars like this one have been left exposed by water action on either side of more resistant rock.

Jim Leach (1920-2000) and Harold 'Budge' Burgess (1918-2000), both members of the Northern Pennine Club, made their way along this dry valley on 24th August, 1947, seeking out new entrances into the Gaping Gill system.  The war had been over for two years, and caving was entering a new golden age of exploration as cavers looked up old friends and headed back to their former 'stomping grounds' ...

At noon they came across this feature - a deep shakehole in an unusual position on a ridge, and very easy to miss.  The bottom was full of nettles and small boulders barring the way into an obvious cavern.

This is the initial impression ...

Photograph by kind permission of John Cordingley

The ridge containing Body Pot can be seen very well at the centre of this photograph.  A line of rushes marks the 'sink' into the hole which can still be quite powerful in flood conditions.  Ingleborough and Little Ingleborough dominate this view, looking north west.

Jim no doubt tackled the nettles before crawling inside, with Budge following him.  Removing a few small boulders, they descended into a small chamber, and, on climbing down, noticed a pair of shoes protruding from beneath a large rock.  Seconds later it was apparent that the shoes were in fact attached to a skeleton.  The body was mainly decomposed and .. as though the find wasn't daunting enough ... the skull had a plum-coloured scarf knotted around the mouth and wore a trilby hat.  Not only that, but there was evidence that he had, in fact, been 'walled-in' to a cavity - and beside him was a bottle of the lethal poison, sodium cyanide.

This is how the interior of 'Body Pot' appears today. The body was found in this area. The man was forensically examined and was seen to be 5 feet 5 inches tall with sandy hair.  He was estimated to have been dead between 2 and 6 years.  The body was found not only with the poison, but with a toothbrush, spare pair of shoes, a wristwatch, handkerchief, shaving tools, toiletries and flashlamp.  He also had money totalling 11 shillings with coins all older than 1939 and a key was discovered in his rotting clothes.  Jim and Budge had made a startling discovery and investigations went on for months.  

The entrance passage quickly turns left into the chamber where the body was found in an alcove.  Recent digs in an adjacent chamber have probably concealed the actual stone under which the body was concealed.

Looking back from the 'Body' chamber to the entrance slope of somewhat precarious boulders.

The chamber in close-up.

It doesn't take much to imagine a pair of feet sticking out from beneath one of these boulders!

Animal bones cause one to shudder for a second or two ..

Looking into the scaffolded 'dig' of the second chamber.  The scaffolding supports dangerous boulders and it is best left well alone.

Despite the macabre story - there is beauty in Body Pot, too.

The delicate ribs of wonderfully eroded limestone making up the ceiling just inside the entrance are particularly attractive.

The area of Body Pot as seen from the north.  It can be seen from this picture that such a location was well chosen for the resting place, whether or not the man was murdered or, indeed, took his own life.  The hollow - at centre - is well hidden from all sides, with the entrance - though close to a track, not particularly conspicuous until an explorer is right next to it.  Was the man a German spy?  Was suicide involved?  Was he a paratrooper who had 'bailed out' over Britain?  How was he 'walled-in' if it was suicide?  Why was the cyanide bottle presumably full with no evidence of it having been used? Was this a genuine murder case? These questions have, to this day, never been answered.  Interestingly, another body was found in Gaping Gill at around the same time, but was proven to have been undiscovered for considerably longer than the man in Body Pot.  Both matters remain, perplexingly, a complete mystery.

On the return from my wander to this macabre spot, I passed by Clapham Bottoms Pot - once known as the Bradford Folly from an unsuccessful attempt by the club many years ago to connect it with the far reaches of Gaping Gill.  It is surrounded by a low wall and is unsafe at present with loose boulders.  Cavers, as can be seen from the photograph - are doing their best to keep working at it.  There are several underground pitches and squeezes leading into chambers, and the pot clearly has some potential.

The entrance shaft, which has been considerably excavated to wide dimensions, is covered by planks to prevent sheep falling in, as the old wall is unlikely to be of much use.

Another lovely limestone outcrop near Clapham Bottoms Pot.

The Mystery River:  Clapham Beck making its journey down Clapdale having just emerged from its subterranean course at Clapham Beck Head.  It takes several days to make the journey from dropping down Gaping Gill as Fell Beck to its emergence into daylight, and much of its activity underground still remains a mystery.  Limestone country never fails to astonish those who explore it.

Clapham Bottoms and the Allotment from the air.  The Allotment is the reddish expanse of moorland at top right.  The major hole at top centre is Marble Pot, and next largest on the photograph across the wall and down to the left is P5.  Just below P5 is a wall running east/west and over this wall two obvious small holes can be seen darkly in the picture, lined up diagonally.  Body Pot, where the skeleton was discovered, is the lower (south-west) of these two holes (SD758724).  If you wish to follow Jim and Budge's footsteps, take a caving helmet and lamp, and have a change of clothes in the car at Clapham.  The hole is dangerous and there are many unstable boulders, so entry must be made at your own risk. You actually don't need to enter to get a good overall feel of the place. The prominent hole at the extreme bottom of the picture and slightly to the left is the walled entrance to Clapham Bottoms Pot. (do not on any account be tempted to enter this one) This little wander makes a good day out combined with a visit to Trow Gill and Ingleborough Cave, and gives a good understanding of the karst landscape.

I would like to say a special thank-you to John Cordingley, whose knowledge of the dales is second to none - for helping me in so many ways with this project and making sure I picked out the correct pothole from a confusing mass of possibilities in Clapham Bottoms!!  This page wouldn't be what it is without John's help.