axbridgecaver
Member
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!â€
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 “snapperâ€. 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.
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!â€
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 “snapperâ€. 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.