Redhouse Lane on U Tube

Tritim230

Tritim230

Active member
The lack of formations in general is down to the coal measures above. Having said that the floor deposits are exceptional.
 
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Andy Farrant

Active member
The nice scalloped passages in Draenen are in the Gilwern Oolite, part of the Clydach Valley Group, much of which is dolomitised along the east crop. As you go to the south and east, the Clydach Valley Group morphs into the Black Rock Limestone Group, which is heavily dolomitised in the Forest of Dean. I suspect that the nice scalloped passages in Redhouse Lane are in the Gully Oolite Formation (formerly known as the Crease Limestone). This is a younger limestone than the Gilwern Oolite. The Gully Oolite was removed (or possibly not deposited) in the Clydach Gorge area by intra-Carboniferous erosion as it was very close to the contemporary shoreline. But it is a similar rock type, and is not dolomitised, so sculpts well. The notches are similar to those seen in Draenen, and are evidence of a sediment fill. A nice find!
This figure sums it up.

 
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Rhys

Rhys

Moderator
Huge said:
Passages like Indiana Highway, Raiders Passage and The Canyon, which are formed in the Gilwern Oolite.
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Hi Huw. While on a survey trip in these new white passages in Redhouse, it brought back clear memories of the the early Draenen days and an unmuddied Indiana Highway. Great minds...!
 
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Huge

Well-known member
Andy Farrant said:
The nice scalloped passages in Draenen are in the Gilwern Oolite, part of the Clydach Valley Group, much of which is dolomitised along the east crop. As you go to the south and east, the Clydach Valley Group morphs into the Black Rock Limestone Group, which is heavily dolomitised in the Forest of Dean. I suspect that the nice scalloped passages in Redhouse Lane are in the Gully Oolite Formation (formerly known as the Crease Limestone). This is a younger limestone than the Gilwern Oolite. The Gully Oolite was removed (or possibly not deposited) in the Clydach Gorge area by intra-Carboniferous erosion as it was very close to the contemporary shoreline. But it is a similar rock type, and is not dolomitised, so sculpts well. The notches are similar to those seen in Draenen, and are evidence of a sediment fill. A nice find!
This figure sums it up.

Click to expand...
Cheers for that Andy. 👍
 
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Huge

Well-known member
Rhys said:
Hi Huw. While on a survey trip in these new white passages in Redhouse, it brought back clear memories of the the early Draenen days and an unmuddied Indiana Highway. Great minds...!
Click to expand...
Great minds indeed, Rhys! 😀

Btw, the breakthrough in Draenen happened 30 years ago today! Well yesterday now, as I'm posting this a bit late.
 
Tritim230

Tritim230

Active member
We said that this must be the biggest find since Draenen. The way things are going, it could well be. Not certain how much more we will be able to do this year, if any. Cave has flooded twice and last trip was at the limit of not drowning. It is a dangerous place.
 
Tritim230

Tritim230

Active member
PeteHall said:
Indeed. Digging through the gravel squeeze on Friday with head pressed against the roof and water lapping into mouth and nose was pretty close to my limit!
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Fortunately, I didn't struggle as much there - more a longer dive in Mud Sump, but yes it was a calculated guess using effort + distance and estimating whether I could hold my breath that long! After a long trip, that is some serious exit.
 
Tritim230

Tritim230

Active member
Andy Farrant said:
The nice scalloped passages in Draenen are in the Gilwern Oolite, part of the Clydach Valley Group, much of which is dolomitised along the east crop. As you go to the south and east, the Clydach Valley Group morphs into the Black Rock Limestone Group, which is heavily dolomitised in the Forest of Dean. I suspect that the nice scalloped passages in Redhouse Lane are in the Gully Oolite Formation (formerly known as the Crease Limestone). This is a younger limestone than the Gilwern Oolite. The Gully Oolite was removed (or possibly not deposited) in the Clydach Gorge area by intra-Carboniferous erosion as it was very close to the contemporary shoreline. But it is a similar rock type, and is not dolomitised, so sculpts well. The notches are similar to those seen in Draenen, and are evidence of a sediment fill. A nice find!
This figure sums it up.

Click to expand...
Thanks Andy. I was asking Pete for your views, so perfect timing. The cave is almost entirely in dolomite, but to the west of the main drag along Mindless Optimism (roughly north/south), lies the crease limestone. This is also characterised by smoother mud floors, again with lots of cryogenic calcite. The change between rock types is imperceptible, i.e. no boulder chokes to pass. Interestingly all of the passages off in the crease end at chokes which comprise of marl run-ins. One of which we passed (as shown in Ian's video) the other chokes currently block any further way on in the westerly direction.
 
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Andy Farrant

Active member
The presence of cryogenic calcite suggests that there may be another entrance nearby, to allow the ingress of cold air in winter. Many caves with cryogenic calcite appear to be cold air traps, with an entrance descending down to a cold air pool, think Reservoir Hole, Wookey 20, Shute Shelve Cavern.

I might add that some of the rock in the videos looks very brecciated, so I suspect there is some significant faulting..?
 
Tritim230

Tritim230

Active member
Yes, lots of fault breccia. A common feature throughout the Slaughter system. There is a strong draught throughout the cave, in pretty much every passage. As for other entrances that is an unknown as yet. Certainly nothing from above as we are beneath the coal measures and someway beneath the surface hillside.
 
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