Interesting formation in Fairy Hole Cave - Weardale

Mark

Mark

Well-known member
In 2008 & 2009 we did some work to the current entrance of Fairy Hole Cave

Several trips were made into the cave and we explored as far as the Coral Gallery

on the way out we noticed pyrite type formations in the streamway which could not be seen on the way in?



These were all generally above head height and the only thing I can describe them is like foam bubbles which have become coated in pyrite?

The deposit only appears on the upstream surfaces, which is why you can't see it on the way in it is very fragile (1 - 2mm thick)





Anyone seen this sort of thing before




 
AR

AR

Well-known member
My first impression on seeing the photos is that it's bitumen or suchlike; the quick way to test that would be to bring a piece out and see if it dissolves in white spirit. Otherwise, the nearest thing I can think of are the rust "shells" that sometimes from on iron underground. I'll make enquiries of knowledgeable persons...
 
Mark

Mark

Well-known member
A few more pics of the stuff












Clicking on pic takes you to Photobucket where you can see full size images
 
Rob

Rob

Well-known member
Mark, they look quite similar to some of the formations up Cherticle Aven in Doom:







We simply presumed these were all Chert, but maybe not.....?!?
 
Mark

Mark

Well-known member
Rob said:
Mark, they look quite similar to some of the formations up Cherticle Aven in Doom:

We simply presumed these were all Chert, but maybe not.....?!?
Click to expand...

No Rob, nothing like the Cherticle stuff, these are very fragile like a coating on a bubble, but great to see the Wet West photos again, we need to go back there?
 
kay

kay

Well-known member
According to Andrew Hinde, they are probably an iron or manganese pyrites coating on a soft sediment, many at stream level. They obviously resist water abrasion ( but not caver abrasion!)  There is also similar coating on rugose corals at higher level. I've posted a picture by Pete Monk to the FB page, so if perhaps Pegasus could add that here? Thanks
 
blackshiver

blackshiver

Member
Probably manganese oxides, there is a lot of stream precipitated manganese in Fairies, -and this is entirely different from the Manganese deposits found in Hudgill Burn Mine Cave.
 
M

mikem

Well-known member
Andrew Hinde wrote this article (p.14-16) shortly before this enquiry:
https://www.taysidebiodiversity.co.uk/wp-content/uploads/2015/01/EH41_1-14f.pdf
 
tomferry

tomferry

Well-known member
I might be completely wrong but they look like dead mans fingers mushrooms they vary in shape but I have seen some like that before but only about 8cm tall ?

Only speaking about the last photo .

https://www.google.co.uk/search?q=dead+man%27s+fingers+mushroom&client=safari&prmd=isvn&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj9obGMqPHvAhXC_7sIHWsCBGkQ_AUoAXoECAIQAQ&biw=414&bih=715&dpr=2#imgrc=XmU3-kAXh5mvEM
 
M

mikem

Well-known member
Just to clarify that last set of photos are in Peak District, not Fairy Holes, & he has another of those particular formations (also main discussion is from 5 years ago):
https://www.flickr.com/photos/rob_eavis/8658846616/in/photostream
 
A

Andy Farrant

Active member
Yes, most likely maganese and iron oxides
see Gascoine W., 1982 - The formation of black deposits in some caves of south east Wales. Cave Science, 9 (3): 167-175  and
W.B. White, C. Vito, and B.E. Scheetz ? The mineralogy and trace element chemistry of black manganese oxide deposits from caves.
Journal of Cave and Karst Studies, v. 71, no. 2, p. 136?143
 
Pitlamp

Pitlamp

Well-known member
Isn't there something along those lines in the Speedwell streamway (down the Lower Bung, beyond Rift Cavern)? Maybe even a bit in Peak's Treasury, also derived from the Speedwrll stream when it overflows? (Can't remember exactly where - it may be at the entry to the passage which leads down to SEP Sump.)
 
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