William Bagshaw (UK)
White Scar Cave takes its name from the limestone outcrops or “scars” that overlook the entrance. This part of the Yorkshire Dales National Park is dominated by the ‘Three Peaks’ – Ingleborough, Pen-y-ghent and Whernside. Their distinctive shapes are due to their geological structure, which consists of nearly horizontal layers of grit and shale that rest on the Great Scar Limestone. White Scar Cave was formed under Ingleborough between 400,000 and 100,000 year ago, in warmer periods that occurred between the Ice Ages of the Pleistocene.
In August 1923, Christopher Francis Drake Long, a student on vacation from Cambridge University, discovered a slight fissure on the slopes of Ingleborough. He decided to investigate. Wearing only his summer walking clothes of shirt and shorts, and lighting his way with candles stuck in the brim of his hat, he crawled into the low passage. Spurred on by the distant roar of water, he struggled over jagged stones and across rock pools until, eventually, he found himself at the foot of a waterfall. He continued along a stream passage to a cascade and then returned to the surface to announce his find.
On a subsequent expedition, Long discovered a subterranean lake. Undeterred by the cold water, he swam across it. A massive boulder, later nicknamed ‘Big Bertha’, lay wedged in the passage beyond. He squeezed past, only to find his path blocked by a boulder choke (a jumbled mass of rocks). Long intended to open the cave to visitors. However, in September 1924, he tragically killed himself as a result of depression.
Work to open the cave was by then in progress. The natural entrance passage was too low, so it was enlarged as far as the first waterfall by local miners. Trucks were used to remove the rock spoil, and some of the rails on which they ran may still be seen, embedded in the tunnel floor. Timber paths and electric lights were installed, and the first visitors were admitted on Good Friday, 1925. In those days, there was no mains electricity in the vicinity, so power was provided by a diesel generator housed near the cave entrance.
In 1971, cavers, led by John Russom, literally dug their way upwards through the treacherously slippery and unstable boulder choke that had defeated Christopher Long almost half a century before. They found themselves in a massive cavern. It was so vast that the light from their helmet lamps could not penetrate the gloom to the far walls. The roof had great voids (or “avens”) that soared into mysterious darkness. Thousands of delicate straw stalactites hung in great curtains. They hurried back to the surface to break the news of this major discovery. Subsequent visits established that the cavern was over 90m long and, hence, one of the largest known cave chambers in Britain. It was called the “Battlefield Cavern” because one of the cavers, on seeing its boulder-strewn floor, imagined giants fighting there in prehistoric times. The name has stuck.
Various schemes for opening Battlefield Cavern were investigated, but were rejected either on planning grounds or because they were too expensive. Eventually, in 1990, an acceptable scheme was devised. This involved driving a 65m tunnel to the cavern from a point near the underground lake. The tunnelling was carried out by a family firm from Cornwall that was keen to take on the work because of the decline in the tin-mining industry. Lighting and 400m of additional paths were installed, and the cavern was opened to visitors on 1 May 1991. In 2004, a visitor centre was constructed and has a grass roof to help preserve the landscape of the National Park.
The limestone in which White Scar Cave formed came from an ancient sea. Calcite ooze became mixed with fragments of skeletal remains of billions of tiny marine animals. This ooze gradually became hard rock by recrystallization under the immense weight of the overlying layers of later sediments. The rate of deposition averaged one and a quarter centimetres every 1,000 years. Therefore, the 180m thick Ingleborough limestone took about 15 million years to form.
Eventually, the sea, in which the limestone had been deposited, filled in and the area was covered by vast swamps whose rotting vegetation eventually formed coal deposits. Coal was once mined at the nearby village of Ingleton and a very thin seam of coal may be seen near the cave entrance. The rock floor of the ancient sea is exposed at the cave entrance. The horizontal layers of limestone form the cave roof, but the walls and floor are cut into nearly vertical slate beds.
These slates are 400 million years old and were crumpled into their vertical alignment 100 million years before the limestone was deposited. The boundary between the two is an unconformity. An unconformity is, a buried erosion surface between strata of different ages representing a gap in deposition and the entrance to White Scar Cave is an excellent example of this type of geological structure.
The cave is a Site of Special Scientific Interest (or SSSI) and a Special Area for Conservation (or SAC). An intriguing feature of Battlefield Cavern is the ancient, dried mud pools whose cracked and crazed surfaces have never been disturbed by man. Samples of the stalagmites have been dated by measuring the radioactive decay of the minute quantities of uranium in them. Most were found to be about 100,000 years old, but some formed less than 15,000 years ago. The temperature of the cave is usually about 8°C throughout the year because the rock acts as a thermal stabilizer, eliminating seasonal fluctuations. The main cave stream normally flows at a rate of about 5m3 per minute. In flood, it sometimes runs at ten times this rate, carrying away some 55 tonnes of water every minute.
Insects, worms, shrimps and spiders have been found in the cave. They are mostly of microscopic size, sightless and live off minute traces of organic debris carried in by water. Fossils found so far in the cave include trilobites, simple corals, colonial corals, brachiopods, goniatites and crinoids.
White Scar is an extensive cave system. Therefore, further investigation by enthusiastic fossil hunters is still welcomed, holding out the prospect of further spectacular finds.
All photographs are copyright of William Bagshaw.