Shute Shelve Cavern

[Gina]

Alan Gray and Tony Boycott have reported the presence of CCCs in Shute Shelve Cavern on Axbridge Hill

[axbridgecaver]

Shute Shelve Cavern Cryogenic Cave Calcite

Shute Shelve Hill, Axbridge. NGR - ST 4239 5535

Length – 249m. Vertical Range – 56m.

Historical Background

Shute Shelve Cavern was discovered by the Axbridge Caving Group in 1992 by digging though a small mud/boulder choke which only took two hours giving access to Reynard’s Chamber. The ochre miners had entered this cave by another entrance but they did not explore the lower chambers since the boulder choke at the lowest point of Reynard’s had not been entered.

UBSS Proc. 1993 19 (3) Pages 283 to 290 – Shute Shelve Cavern Exploration, History and Geomorphology by A. R. Farrant and A. Gray has dated the Speleotherms from Reynard’s Chamber to be older than 350,000 years (Uranium Series Dating).

Mud samples analysed by A. R. Farrant, from Box Tunnel, were dated to 780,000 years old (Paleomagnetic Techniques).

A little while after the discovery of this cave Charlie Self, member of UBSS and Geologist, visited the cave and was mystified by the crystal like deposits in a few places on the floor of the cave. He took a sample away and to my knowledge it was not identified. These deposits looked quite different to other cave deposits, so they were taped off for protection.

Trip Report

25 March 2018 – Shute Shelve Cavern/Carcass Cave – Alan Gray, Chris Barrington

Chris contacted me and asked if he could conduct a bat count in Shute Shelve Cavern; what an ideal opportunity to document the Cryogenic Cave Calcite (CCC) that I thought existed in Shute Shelve Cavern.

The first area where it was thought that the deposits existed was the Flat Room, but these turned out to be a thin layer of flowstone with small gour pools.

Site 1 – Half way down Box Tunnel, adjacent to the entrance to Elm Street and in the centre of the passage, the first deposit was located. It is over an area of 2.6m long and 1.6m wide with scattered deposits at the top and bottom and a concentrated deposit in the centre. The form of the deposit is small flakes up to 4mm long. This deposit is at a depth of 43m from the entrance, the passage width is 9.5m and the roof height is 5.5m.

Site 2 – Towards the end of Box Tunnel, and in the centre of the passage, the second deposit was located; it is far more extensive than the first. It is over an area of 7m long and 3.5m wide with scattered deposits at the top and bottom and a concentrated deposit in the centre. There also appears to be crystal like flakes deposited on small outcrops of mud attached to the near vertical faces of rocks. The form of the deposit is small part spherical and small flakes up to 4mm long. This deposit is at a depth of 53m from the entrance, the passage width is 6.5m and the roof height is 3.8m.

Small samples of the deposits were taken from both sites.