• Descent 302 is published on 15 February and it will soon be on its way to our subscribers.

    In the newsdesk, read a review of the underground events at Kendal Mountain Festival, plus tales of cannibalism and the Cavefish Asteroid.

    In regional news, we have three new connections in Ogof Agen Allwedd, a report on the iron mines of Anjou, an extension to Big Sink Cave in the Forest of Dean, a new dig in Yorkshire's Marble Steps Pot, student parties, an obituary for Tony Boycott, a tight find in the Peak District and a discovery in County Kerry with extensive formations.

    Click here for details of this edition

Redhouse Lane on U Tube

Rewitten as edit time expired Grrrrrr.

During permafrost conditions near the edge of the glacial sheets water in caves froze solid to become a mass. The movement within the solid mass created breakdown and fracturing of formations clearly seen in Reservoir Hole and Shatter Cave on the Mendips. Over time many fractured formations were covered with more calcite to leave formations like The Leaning Tower of Pisa in Shatter. Also see my recent image on the photo section of the tipped up stal boss in TFD shown again here.



WL Cave shows lateral shearing as solid ice moved withing the passage. With warmer interglacials vast amounts of water were released forming epigenic caves possibly like you have in the FOD. Mendip caves went through cycles as water levels dropped. The transition from phreatic to vadose is clearly seen in Shatter Cave. TFD has superb mud floors having dried and cracked as the water table dropped also residual cryogenic calcite structures on some boulders.
 
Two other videos from 14th and 28th September were also posted yesterday - they can be seen if you go to YouTube itself on original link (the perched rocks are presumably also left by melting ice, whilst tea green marl is later infill)
 
Two other videos from 14th and 28th September were also posted yesterday - they can be seen if you go to YouTube itself on original link (the perched rocks are presumably also left by melting ice, whilst tea green marl is later infill)

That's the working theory regarding the random perched rocks. Left behind stranded on ledges after partial ice fill melted away.
 
We believe the 'black' in Crack in Black is coal, possibly from washings above. We've taken a sample to dry and see if it burns!
 
Two other videos from 14th and 28th September were also posted yesterday - they can be seen if you go to YouTube itself on original link (the perched rocks are presumably also left by melting ice, whilst tea green marl is later infill)
The crease limestone is very evident on the video of 14th September as is the abundance of Cryogenic Calcite
 
Is it the pointy end or the round end of the scallop that points upstream?
The easy way to tell is to run your hand over the scallops. In one direction, it will flow smoothly and that it the direction of flow.
Running your hand the other way feels much more bumpy.
 
As an occasional digger and cave surveyor in the Forest, I’ve been fortunate to be welcomed along with the team for a couple of trips helping out in the new bits of Redhouse. It really is a stunning find. The sheer scale of the large breakdown passages is so unexpected and some of the (smaller but still comfortably walking size) phreatic passage shapes further in are really nice. There’s a lack of classic flowstone formations, but tons of other nice features to enjoy. I think people automatically assumed that the cave would just link up with Wet Sink, but at the moment it’s doing its own thing and heading into blank space – which is really intriguing. Credit to Tim and the core team for the hard work and thank you for having me along – it’s really appreciated.
 
During permafrost conditions near the edge of the glacial sheets water in caves froze solid to become a mass. The movement within the solid mass created breakdown and fracturing of formations clearly seen in Reservoir Hole and Shatter Cave on the Mendips. Over time many fractured formations were covered with more calcite to leave formations like The Leaning Tower of Pisa in Shatter
And Wookey Hole; there's plenty on show in there which is testament to this proces (off piste from the showcave).
 
Fantastic find! Congratulations to everyone involved. Let's hope there's plenty more to come!

I've got a geology question, if anyone can answer? The passages shown in the videos look incredibly similar to passages in Draenen. Not just the large, bouldery passages but also the smaller, well scalloped passages in the lighter coloured limestone. Passages like Indiana Highway, Raiders Passage and The Canyon, which are formed in the Gilwern Oolite. I know that the limestone in the forest is related to the limestone in South Wales but I wondered if they are actually the same beds but given different names?
 
I think this is the FOD limestone.
Llanelly Formation


A pale limesone with a significant algal content in places. Still oolitic I believe
 
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