Compared to many of the super-gnarly reports that go up on here, this is seriously tame. It doesn't involve any dodgy access, any death-defying leaps of faith or even meeting another human being - it just involves one bloke, a camera and some picturesque (in my opinion) tunnels carved into the solid (and not so solid) rock. I just hope that someone out there finds it vaguely interesting!
Jet - some background
Jet is famous in the part of North Yorkshire that I'm from - classed as a minor gemstone, it's been in favour for millennia but really started to come into vogue during the Roman Occupation and then jet became much sought-after once Queen Victoria used it as part of her mourning dress after the death of Albert. Given it was in such huge demand at one point, it seems strange to think that it's just fossilised wood (there are two types: hard and soft, depending on what kind of water was present during the high-pressure sedimentary processes that formed it).
In North Yorkshire, jet is predominantly found in the geological strata of Whitby mudstone, a sedimentary bedrock formed almost 200 million years ago. This mudstone makes for rather unstable tunnels though and is incredibly soft to the touch, crumbling away in your hands should you touch the side of the tunnels. The majority of jet mines in Guisborough adhere to this principle although some are driven into the boundary between the Whitby Mudstone, Staithes Sandstone and the Cleveland Ironstone layers. In many of the Guisborough mines, there is also a significant quantity of oil-bearing shales which stain your hands something terrible (and also have led to issues with combustion in some mines in the past).
Anyhoo, you haven't popped by to read a load of guff about geology etc. You want some photos. There are several mine entrances in Guisborough Woods - some are easily accessed, some require more effort and some look like plain out and out deathtraps. For the sake of this report, I've restricted my explorations to two mines: Mine 1 (I gave it the arbitrary name Gemini) and Mine 4 (Fat Man's Agony)
Mine 1 - Gemini
Extremely easy to access, being located a few metres from a forest fireroad, Mine 1 is a diminutive little beastie driven into the mudstone formations and therefore very colourful but muddy, damp and with plenty of that bituminous shale content which can wreck clothing and also stinks. Gemini is so named as it has twin entrance/exit portals around 5 metres away from each other:
The right portal, looking out into a rainstorm.
The left portal, complete with years' worth of detritus.
Once inside and down the steep little muddy slope, you're faced with a criss-cross grid pattern of tunnels and cuttings, many ending in collapses now as the workings are relatively close to the surface and heavy forest machinery has taken its toll on the roof.
Entrance/exit to the right, behind to a collapse, left to another collapse so it's time to go straight on!
Steep little slippery slope up to another level within the mine.
Looking back down the slope towards the entrance crossroads.
Here are four shots of the various tunnels that run off from the top of the slope:
That yellow mineral/rock formation crops up a lot in various places around the mine. I would have thought it had a high sulfur content, but the scratch 'n' sniff test said otherwise:
There's also plenty of calcination going on in and around those oil-bearing shales:
There is one long tunnel running off from the bottom of the sleep slope that bears significant pick/hammer marks in the ceiling - the very soft mudstone/clay combination means it's very easy to leave imprints in the roof and walls.
The cutting that links the two exits/entrances together has an old cable reel lodged in one end:
There was also a practically-fossilised turd in this cutting too, courtesy of some previous minephile who couldn't hang on to his bowels any longer - cheers dude!
Mine 4 - Fat Man's Agony
This one has a bit of a squeeze into the entrance (again, two are possible) but once inside is much bigger than Gemini. It's also in a slightly different geological formation as the walls are harder rocks (sandstone/ironstone formations most likely).
There's a small red can up on the ledge here but I've no idea whether it's an artefact from a hundred or so years ago - looks in too good condition to have been left down here (this part is very damp) for that long.
Some original roof timbers as a token support for thousands of tonnes of sedimentary rock!
Another short scrambly bit.
Another bit of a squeeze over this rock step - spot the string on the floor from a previous exploration.
How low can you go?
Fantastic Mr Fox - The Director's Cut
And there you have it - as I said earlier, nowt flash. Hope you enjoyed it!
Jet - some background
Jet is famous in the part of North Yorkshire that I'm from - classed as a minor gemstone, it's been in favour for millennia but really started to come into vogue during the Roman Occupation and then jet became much sought-after once Queen Victoria used it as part of her mourning dress after the death of Albert. Given it was in such huge demand at one point, it seems strange to think that it's just fossilised wood (there are two types: hard and soft, depending on what kind of water was present during the high-pressure sedimentary processes that formed it).
In North Yorkshire, jet is predominantly found in the geological strata of Whitby mudstone, a sedimentary bedrock formed almost 200 million years ago. This mudstone makes for rather unstable tunnels though and is incredibly soft to the touch, crumbling away in your hands should you touch the side of the tunnels. The majority of jet mines in Guisborough adhere to this principle although some are driven into the boundary between the Whitby Mudstone, Staithes Sandstone and the Cleveland Ironstone layers. In many of the Guisborough mines, there is also a significant quantity of oil-bearing shales which stain your hands something terrible (and also have led to issues with combustion in some mines in the past).
Anyhoo, you haven't popped by to read a load of guff about geology etc. You want some photos. There are several mine entrances in Guisborough Woods - some are easily accessed, some require more effort and some look like plain out and out deathtraps. For the sake of this report, I've restricted my explorations to two mines: Mine 1 (I gave it the arbitrary name Gemini) and Mine 4 (Fat Man's Agony)
Mine 1 - Gemini
Extremely easy to access, being located a few metres from a forest fireroad, Mine 1 is a diminutive little beastie driven into the mudstone formations and therefore very colourful but muddy, damp and with plenty of that bituminous shale content which can wreck clothing and also stinks. Gemini is so named as it has twin entrance/exit portals around 5 metres away from each other:
The right portal, looking out into a rainstorm.
The left portal, complete with years' worth of detritus.
Once inside and down the steep little muddy slope, you're faced with a criss-cross grid pattern of tunnels and cuttings, many ending in collapses now as the workings are relatively close to the surface and heavy forest machinery has taken its toll on the roof.
Entrance/exit to the right, behind to a collapse, left to another collapse so it's time to go straight on!
Steep little slippery slope up to another level within the mine.
Looking back down the slope towards the entrance crossroads.
Here are four shots of the various tunnels that run off from the top of the slope:
That yellow mineral/rock formation crops up a lot in various places around the mine. I would have thought it had a high sulfur content, but the scratch 'n' sniff test said otherwise:
There's also plenty of calcination going on in and around those oil-bearing shales:
There is one long tunnel running off from the bottom of the sleep slope that bears significant pick/hammer marks in the ceiling - the very soft mudstone/clay combination means it's very easy to leave imprints in the roof and walls.
The cutting that links the two exits/entrances together has an old cable reel lodged in one end:
There was also a practically-fossilised turd in this cutting too, courtesy of some previous minephile who couldn't hang on to his bowels any longer - cheers dude!
Mine 4 - Fat Man's Agony
This one has a bit of a squeeze into the entrance (again, two are possible) but once inside is much bigger than Gemini. It's also in a slightly different geological formation as the walls are harder rocks (sandstone/ironstone formations most likely).
There's a small red can up on the ledge here but I've no idea whether it's an artefact from a hundred or so years ago - looks in too good condition to have been left down here (this part is very damp) for that long.
Some original roof timbers as a token support for thousands of tonnes of sedimentary rock!
Another short scrambly bit.
Another bit of a squeeze over this rock step - spot the string on the floor from a previous exploration.
How low can you go?
Fantastic Mr Fox - The Director's Cut
And there you have it - as I said earlier, nowt flash. Hope you enjoyed it!
