Pridhamsleigh Cavern, New Crack above Bishops Chamber

[Jason Pain]

DCUC Advisory

Pridhamsleigh Cavern, New Crack above Bishops Chamber

11th April 2015


This week reports have been received from a number of sources about what appears to be a new crack in the ceiling of Bishops Chamber in Pridhamsleigh Cavern.


On investigation today by Roger King DCUC Access Officer, we believe a new crack ( or at least an old small crack is on the move) in the roof has opened up at a right angle to the open end of the trench in Bishops Chamber.  


Some of the edges look clean, and fresh looking material from the crack has been observed on the floor.


We advise users to be cautious in this area, and would ask regular users to help monitor the situation and report to the DCUC Access Officer any observations, if possible I know some of you take cameras with you, any pictures (with dates) of the crack would help us to create a pictorial log of changes.


DCUC Access Officer email address

access@dcuc.org.uk



DCUC will continue to monitor the situation and advise further as appropriate. 


Regards


Jason


--


Jason Pain

Secretary

Devon & Cornwall Underground Council (DCUC)

secretary@dcuc.org.uk

 

[Joe90]

I'm guessing its an extension to the crack that has been there for years with the lose bits that wobble when poked?

Any pictures??

 

[Jason Pain]

Unsure as I've not seen it myself, however a number of regulars think it is new or has recent development, hopefully with people aware we can get a wider consensus and hopefully some pics to compare.

 

[Joe90]

There was always a section that had been tip-exed across the crack, maybe somebody has the width noted down somewhere.

I'm afraid i have no pictures from before the new reports but from some good ones I know how it should look.

 

[Jason Pain]

All input welcome Jo

 

[caverbabe]

Hi Peeps, been down two times to observe and it does appear to be an extension of an historic fracture.  I'm unsure of the mechanism that has extended this, and there is evidence of some small amounts of localised spalling.  I'm intending on installing some small monitoring pins (unobtrusive but useful) and I have dedicated a tape measure and a set of calipers for regular measurements.  I will post info of the locations when they are installed.  I've kept in touch with DCUC on the matter and have advised that all outdoor centres and cavers who use the cave are notified, as well as the cave owner.  I'll pop back and let people know if there is any measured movement, but at this stage except for not standing directly under the roof to the right of the trench, or in the trench itself, the risk is assessed to be moderately low. Of course no one can ever say with any certainty if or when a rockfall will occur, but as others have noted this is an historic fracture which has extended and there are no signs of obvious displacement or imminent failure, so just use some common sense - and please make sure people don't poke around at it or my monitoring pins!  Thanks peeps, cave softly.