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Tankard Shaft Dig

Duncan S

Duncan S

New member
tony from suffolk said:
Considering you've an icy-cold draft coming up from the bottom of the dig, isn't it strange that the air quality is so poor?
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My hypothesis is that the draft is formed by percolation.
The Mendip plateau is nearly all farmland and no indication that this huge catchment area drains any other way than straight down through the fields.
Percolation should take the air on the surface when the rain falls, which in this case means under the thick matted grass in the fields. Both the rotting vegetation at ground level and the active grasses give off CO2 and CO2 is heavier in air. I haven't researched this, but I suspect the air below the grass will be very high in CO2, and it is this air that is making it's way into the caves.

Hopefully the coldness of the air indicates it is going to great depth before drafting out of Tankard Shaft.
We need to measure the temperature at our dig and compare it to other drafting digs in the area to see if there is a real difference, or whether it is just our perception.
 
The Old Ruminator

The Old Ruminator

Well-known member
I would say a colder and steadier draught at Vurley this week. Of course a draught will not necessarily blow CO2 from a cave as the gas is heavy and can lie in pockets or at the bottom of shafts. Therefore it is a myth that a strong outward draught " freshens " up a cave.
 
tony from suffolk

tony from suffolk

Well-known member
Now look here Tankard Shaft folk! I don't wish to nag but, having whipped us crumbly old armchair cavers up to a frenzy of excitement (I was drinking two cups of cocoa a night!) you've latterly been rather dilatory on the "Finding Caverns Measureless To Man" front. So come on now, give up those silly little day jobs & knuckle down to it, there's good chaps and chapesses! You owe it to your many senile fans.
 
Duncan S

Duncan S

New member
Morning Tony  ;)
We still haven't been back down Tankard!
Patience please...

It'll probably be a few more weeks before the first trip of the Winter season as I have to fetch my fianc?e from the far North and the team will be short-handed till then.
When something happens it will definitely be reported here :)
 
Leclused

Leclused

Active member
Duncan S said:
Morning Tony  ;)
We still haven't been back down Tankard!
Patience please...

It'll probably be a few more weeks before the first trip of the Winter season as I have to fetch my fianc?e from the far North and the team will be short-handed till then.
When something happens it will definitely be reported here :)
Click to expand...

I'm also waiting for the next episode.

BTW Didn't you go on expedtion in spain? If so how was it? I went to the PSM in September :) Also so the vid about Sima Regalo.
 
cooleycr

cooleycr

Active member
It was only 'cause I got mud in it from a sloppy kibble on Sunday -  ;)  oh look, still there....

don't worry though, we have reserved a small space on the plaque for part-timers  :clap:
 
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