Peak Cavern Hydrology - (split from Bradwell catchment topic)

[bograt]

When Bentham and Sutton did their dye testing in the mid 80s on Eldon hill adjacent to Eldon Hole east side, they used a bowser full of water borrowed from a farm. This water was poured down an excavated sink hole, I seem to remember the results being written up in the EPC journals.

T pot

I remember this exercise, Dave Watson from Peakshill managed to get the use of a large Bowser (can't recall the volume, but it was BIG), they put the dye at the lowest point of the shakeholes and let the water go to flush it through, I believe the results where quite encouraging, but I never read them. (I do recall a few suspicious stains at the bottom of a few shakeholes for weeks after----!!)

Worth remembering that some drainage in the Dirtlow area of the catchment has been traced to Ink Sump, (can't remember where I got that from).

 

[pwhole]

It was traced from Hollandtwine, certainly, presumably from the 'Great Swallow'. Hazard never seemed to need drainage, but that was probably as it ran into Hollandtwine, if there was any. I do wonder how much Pindale Sough actually takes away too, as I don't know what tests (if any) have ever been done on that one. But I would imagine a considerable amount - from Dirtlow Rake at least. It never went any further than Siggate Head, if indeed it reached there, but the tuff must have affected water movement considerably around there, so I'm unclear what happens further along the rake. The sough is 'available' in Pindale End mine, but it's very silted up at the shaft bottom, but that remains an interesting possibility in a dry summer. There was also a branch from Kronstadt Sough toward Dirtlow Rake too, but it was never explored by Blue Circle owing to too little airspace (at the time).

 

[mch]

In the late 1980s I believe that the outer end of Pindale Sough was silted up so presumably there was no flow at that time. Alan Medhurst dug it out as far as the first airshaft but I don't know if any further work was done there.

 

[Mrs Trellis]

Re Ink Sump - in 2009 there was pollution in the sump following waste paper dumping.

Possibly more interesting is where the main stream flow in Far Sump comes from.

 

[mch]

With regard to the Eldon Hill dye testing there will be some details of this (including a couple of archive photos) in a feature within the next issue of The Derbyshire Caver, out in about a month's time, so get your ?2s ready!

Mike Higgins
DCA Newsletter Editor

 

[AR]

Hazard and Hollandtwine would actually be outside of the scope of this as they're in Castleton liberty!

 

[mch]

Hazard and Hollandtwine would actually be outside of the scope of this as they're in Castleton liberty!

Sorry AR - a senior moment!

 

[Pitlamp]

Re Ink Sump - in 2009 there was pollution in the sump following waste paper dumping.

Possibly more interesting is where the main stream flow in Far Sump comes from.

The main input in Far Sump is a small passage with an often powerful flow near the upstream end. This has been explored for 46 moderately desperate metres to where the way splits on a vein with a flow coming from each direction. Both require digging but both are difficult spots to work in. The main Peak Cavern stream originates from this spot.

There is an article in the most recent TSG Journal (No.18, 2010, pages 36-38) which discusses what is known about the hydrology of this "main feeder". It concludes that the majority of the flowing water is from an unknown source. The article includes images of the terminal choke to the left at the T junction and the prominent vein met therein.

I agree; it would be of great value to track down the ultimate source of this powerful flow of water.

 

[Rob]

I agree; it would be of great value to track down the ultimate source of this powerful flow of water.

I would say the water has got to be almost 100% allogeneic, so the "source" would in fact simply be an area of land.

I'm sure in fact you know this already Pitlamp and that you agree the more interesting opportunity is finding a way into any flowing waters upstream of here. The Flatmate has got to be a likely candidate.

 

[Pitlamp]

I think  the source of Far Sump's main feeder is largely autogenic (which is what I think you meant?). Its clarity and "smoothed out" flow characteristics are typical of what cavers refer to as "percolation water". If you want my bet it's probably coming from a wide area of upper Cavedale. It's older stuff dropping into this flow which would be interesting. More promising (for westwards extension) is Cliffhanger Sump, although this would probably need a fairly ambitious effort (and permissions) to drain it with a deep channel. One of our Derbyshire Section lads is diving it; I asked him to get an accurate depth at the end (on a dive computer) which would be useful intelligence if ever digging a channel is being contemplated. (Just mentioning here so folk are aware that this information should be available shortly.)

 

[Rob]

I think  the source of Far Sump's main feeder is largely autogenic (which is what I think you meant?).....

Yup, thanks. Always get those two words muddled up!

Keep us updated about Cliffhanger, it is indeed a prime location.

 

[Mrs Trellis]

It's all Greek to me.

Auto - self ; allo - other. Still there in modern Greek eg  ?????????? - motor car (lit. self movement) and ????? other, else and ????? elsewhere.

 

[Pitlamp]

. . . but an interesting contribution Mrs.T.

Just for anyone who genuinely isn't familiar with these two words:

Allogenic water in cave systems is characterised by having gone underground as a discrete stream. Good examples are the many Rushup Edge swallets. Allogenic streams typically respond fast to rain but flows subside fairly quickly after rain stops, resulting in very "peaky" flow patterns.

Autogenic water is what cavers often refer to as "percolation water". Rain just soaks into the limestone catchment without first forming discrete streams. A reasonable example here is (probably) the Ink Sump stream in Peak Cavern. Autogenic waters typically take a longer time to rise after wet weather starts, don't come up as high in a single weather event as you might expect a comparable allogenic stream - and also subside more slowly. The incredibly complex matrix of flow paths within the limestone has the effect of creating inertia to some extent in the hydrological system, smoothing out flows as rainfall varies. (This is why, for example, Sleets Gill Cave in the Dales can suddenly flood two or three days after the onset of fine weather, then stay up flooded for a fairly long time; it's a well known hazard which has almost caught people out several times.)

In practice of course the above are two extremes of a very wide spectrum of water origins in cave systems, which is why the profile of a flood pulse can be quite complex. (The Peak Cavern system is a particularly good example of this, even being made more complex by the celebrated siphoning effects.)

Having said all the above I'm just a scruffy caver - not a professional hydrologist. So others may well improve on my own thoughts. But that's my understanding anyway, in case it helps.

 

[pwhole]

As far as I remember, a dye-trace done via the lonely shaft in the big triangular field adjoining New Rake on the south side, and roughly above Far Sump Extensions, proved positive in the Main Stream Inlet - I'm sure Pitlamp can qualify this (or a more specific detector site, anyway), as I think it was reported in a CDG Newsletter.

Anyway, to save anyone the bother now, the TSG re-investigated this shaft a few years back. It proved to be a very shallow climber, which linked via a short descending passage to a totally backfilled larger shaft, almost invisible on surface due to overgrowth. A window in the large shaft wall was now a solid wall of deads. Jumping up and down on the surface rubble was easily detectable from beneath, so it's unlikely that without a massive excavation, there's not much can be done here. But the positive test (if I'm correct) was very useful. I think the other positive was from the Titan West Passage shaft.

Photos here: http://www.pwhole.com/photo_galleries/private/HurdlowShaft/

 

[Big Jim]

I assume everyones seen this published last year..... http://nora.nerc.ac.uk/511287/1/KG@B%202015%20Carboniferous%20field%20guide.pdf

 

[pwhole]

Nope - didn't even know it existed. But thanks for letting me know!

 

[Big Jim]

Me neither Phil, I was just googling summut t'other day and it came up. Thought it was old until I saw date on it but presumed it must have been publicised somewhere on here already.  Nice to see pic of John Beck crawling out of Convenience Cave.

J

 

[pwhole]

And nice to see Pit Props Series (Ford's Cavern) get a tangential mention too - that's some justification for the re-surveying job at least

 

[Pitlamp]

I'd have to do a fair bit of searching through CDG NLs to remind myself about that mine shaft in the triangular field which got dye tested (over Far Sump Extension) - it might be easier if you glance in one of the TSG Journals which has articles about Far Sump Extension; it's all in there.

 

[pwhole]

I'm struggling to find it in any from 11-18, though I have read it somewhere, as we checked the shaft based on that account - it may be on the TSG forum. One detail I do remember was that the vein alignment of the small shaft was not roughly NW, as supposed, but 105?/285?, which was the same bearing as the vein in the inlet.