Easier ways to discover new cave passages!!!

I have been digging for new caves or digging within existing caves searching for new passages for a long time. There have been some successes a 40m long extension in Goatchurch Cavern and the entry into the large chamber in Shute Shelve Cavern both on the Mendips. However most of the time is spend wrestling with boulders, scraping away at mud and hauling heavy buckets – very slow progress. At the end of the main chamber in Shute Shelve the ACG excavated down some 10m and were stopped because we were not permitted to use explosives to remove the large boulders stuck in mud and ochre. We were not using any Scientific methods just following the end cave wall – the way on could be 10m higher and 1m to the left.

How do we determine where to dig –

Your experience as a digger
Bring in a Geologist “who states this looks good – but caves are where you find them!”
Dowsing – seems slightly hit or miss
Resistivity Readings – Inconclusive

Science should be brought into cave digging the main reason being that it will save fruitless months/years of hard backbreaking work that usually finishes not with a breakthrough but with the diggers getting fed up.

The methods used to discover oil fields could be employed. A shock wave is sent into the ground by causing explosions or vibrations at the surface. The shock waves travel at different speeds depending on the type of rock they are travelling through. When the waves hit an interface between two different types of rock they are reflected and return to the surface. Microphones and recording instruments pick up the returning shock waves. Computers can then be used to calculate the positions of the rock layers from the time the waves take to return to the surface. A detailed cross-section of the area can then be produced.

For discovery of cave passages you are searching for airspaces within the rock. The vibrations could be induced with a lump hammer or “snapper”. Microphones (Transducers) could be placed at strategic points in the cave or above ground these would have to be wired, probably via an amplifier, to a laptop. The resulting signals could be analysed and the airspaces in the rock would be revealed on screen.

What do other diggers think –

Is it feasible
Has it been done before
What equipment would be required
How much will it cost

By the way I have spent the majority of the weekend searching for the Lost Cave of Axbridge digging mud from a tiny passage and hauling many buckets, just following an air space.
 
I was one of the original diggers at the end of Shute Shelve many years ago and was very frustrated that, after bashing our way through the hard haematite, the large passage came to an abrupt end. Some of the methods you suggest are used in Civil Engineering and doubtless someone will know about them, but the equipment is probably very expensive and the results may need a specialist to interpret. However, it's time someone took this approach and I hope you get a response to this thread.
A method I would like to try is Ground Penetrating Radar, now widely used in archaeology and I believe the cost has come down and the equipment is now much more compact - you used to have to haul it around on a trolly!
If you want to consult a geologist you could try the Axbridge ex-member who works for the BGS - you know who I mean, it's frowned upon to give names. Shute Shelve features in his PhD thesis, and the ACG have a copy of it.

Good luck.
 
A

andymorgan

Guest
Sounds like a good idea. I think sometimes digging does need more scientific. I was having similar thoughts the other night but using radio waves at the frequency the Heyphone uses. I don't know much about them but I wondering if they travel at different speeds through airspace and rock. I think they probably wouldn't after careful thought...

It seems the shock method is tried and tested and will probably give good results. Perhaps you could contact oil companies for help and sell it to them as a sort of sponsorship!
I was also thinking of using a cruder technique of using a drilling rig, that they use to take rock cores to find out the geology of the rock. If a void is found then an endoscope-type camera could be lowered to have a look!
 

Hughie

Active member
Seismology isn't new to caving - I've heard of some South Wales cavers that use this method.
SMCC are currently using Geo-physics in their efforts at Gibbets Brow.
Not sure if many land owners would be very happy about mobile drilling rigs.

All these methods are, I believe, very expensive, hence not widely used. It is, after all, only a hobby and there is a limit on how much people will spend. Digs can get very expensive - currently our favoured site has cost somewhere approaching £12000! - without any seismology or other such cave locating assistance.

Actually the best aid to cave locating that we've come across is a 360deg excavator!
 

Pitlamp

Well-known member
A useful aid to discovering caves is spending wet afternoons in the club library researching our caving literature. Dowsing is at best useless but more commonly worse than useless since some people seem to give credence to the "results". I really don't want to start (yet another) debate on the latter but I would definitely recommend the former.
 

cap n chris

Well-known member
bubba wrote:
How has it cost £12k?


If you have seen Templeton Pot you will be asking "how has it only cost £12k?"

A) It goes all the way to Australia

122_2208.JPG


B) You can see it from space

aerialtempletons.jpg
 

cap n chris

Well-known member
You'd best ask the diggers about that, Bubba.

Titan, Schmitan, perhaps?...... (probably not, `cos it'd go beneath sea level if it was).
 

Johnny

New member
cap 'n chris said:
You'd best ask the diggers about that, Bubba.

Titan, Schmitan, perhaps?...... (probably not, `cos it'd go beneath sea level if it was).

:LOL:

I was down there on Sunday and one of the blokes present is a civil engineer, involved in sinking shafts, he recons that to do the job commercially would have cost an absolute fortune, certainly hundreds of thousands of pounds.

As for techniques for cave location: research and luck, probably
 

graham

New member
pitlamp said:
A useful aid to discovering caves is spending wet afternoons in the club library researching our caving literature. Dowsing is at best useless but more commonly worse than useless since some people seem to give credence to the "results". I really don't want to start (yet another) debate on the latter but I would definitely recommend the former.

Thoroughly agree on both counts. :D
 
C

cucc Paul

Guest
Limestone by its nature tends to be fractured due to the uk getting shunted about by mountain building events (rocks bend apparently) however i would have thought seismology surveys should be able to identify common cracks with cave i spent a practicle pouring over one last year interpritting the results can be tricky as for equipment... any one know any uni geology lecturers who like caving??? or a phd student who can get hold of the equipment
 

langcliffe

Well-known member
cucc Paul said:
i would have thought seismology surveys should be able to identify common cracks with cave

How? Seismological surveys depend on either the induced shock waves being refracted off the surface of a denser materialor by the shock waves being reflected off the surface of a denser material. Cracks would lose the shock waves altogether.

In theory it would be possible to have a very dense array of detectors and pick up shadow zones, but I really doubt that it would be practical. It would depend on having a refractive surface at a convenient depth, a vast number of detectors, and some horrendous analysis of the results. Moreover, if you're dealing with depths of more than a few metres it would require one hell of an initial thump.
 

AndyF

New member
The best tip for finding cave I think is perhaps the most obvious, follow water or follow a draught. Both must lead somewhere...

I don't generally do completely filled passages unless they are horizontal. Fully filled pots are usually going to lead to fully filled passages IMHO

I like dry, solid passages filled with shoebox size rocks best :D Not many of those around though...
 

paul

Moderator
langcliffe said:
cucc Paul said:
i would have thought seismology surveys should be able to identify common cracks with cave

How? Seismological surveys depend on either the induced shock waves being refracted off the surface of a denser materialor by the shock waves being reflected off the surface of a denser material. Cracks would lose the shock waves altogether.

In theory it would be possible to have a very dense array of detectors and pick up shadow zones, but I really doubt that it would be practical. It would depend on having a refractive surface at a convenient depth, a vast number of detectors, and some horrendous analysis of the results. Moreover, if you're dealing with depths of more than a few metres it would require one hell of an initial thump.

That's a thought - set off a big enough explosion to detect the possible cave beneath and voila - you create your own cave (albeit more of a large shakehole)! :wink:
 
A

andymorgan

Guest
AndyF said:
Fully filled pots are usually going to lead to fully filled passages IMHO

depends on the geology of the area. A lot of the Mendip caves had chocked pots at least near the surface, and opened into reasonable sized passage
 

AndyF

New member
andymorgan said:
AndyF said:
Fully filled pots are usually going to lead to fully filled passages IMHO

depends on the geology of the area. A lot of the Mendip caves had chocked pots at least near the surface, and opened into reasonable sized passage

I should be a bit more specific.. The sort of site I would avoid is one that is heavily filled with silt. A rock/boulder fill is different. It's not to say none of these sites ever goes, but with so many good sites around, I prefer to go on the ones with higher probability.

There are, for instance, hundreds of filled shakeholes on Llangattock, but it's usuallly the rocky filled ones that blow through the snow.

We have one fully filled phreatic on the go at the moment, but I've never succesfully dug a silt filled pot.

I'd always look for draught or water flow as a first choice...
 
Hi chriscastle46

The last passage in Shute Shelve is 120 feet long, 60 feet wide and 20 feet high and was formed by a river flowing through it, totally filling the passage. The mud deposits at the end have been dated to 0.75 million years old. When we came to the end of the passage there was a small air gap which over a five year period many diggers excavated down about 30 feet. At the bottom were large boulders firmly fixed in mud and ochre which we were banging. Unfortunately banging is not now allowed and so the dig cam to a halt. However an air line has been installed and when the cave is reopened in May 2006 digging will recommence. A river that created a cave that size just can't vanish.

I will contact the gentleman you suggest and ask his advice. I think the problem might be that cavers require a great depth whilst archaeologists are quite happy with a few feet. Great depth = high cost and large machines!
 
Top