Well what do you know! Should have brought the camera as all the Hallowe’en decorations were out, there were ghosties, ghoulies, skellies, coffins and things floating in the sump pool. What can you say!
Up at the dig the skip was trimmed to shape, the rope was attached, the slope smoothed over and ready to go. It’s very warm work swinging the mattock, then shovelling the sediment into the skip for removal, keep going until you start to overheat and then swap around. A lot of spoil was shifted and there’s a whole lot more to shift!
Three days of field schools with Peter Hardy, author of ‘The Geology of Somerset’ and Gill Odolphie, Adel Avery and Juliet Lawn from the Somerset Earth Science Centre. In conjunction wit the Geological Society’s Earth Science Week.
Day 1, 12th October:
After an introduction to the chronology of Mendip Rocks from the Silurian c.443 million years ago to the end of the Jurassic c.142 million years ago, and discussions regarding the formation of the Mendip Hills during the Variscan Orogeny we jumped onto a mini-bus for a tour of some local quarries.
At Moon’s Hill we examined the Silurian pyroxene andesite, lavas, fault features and breccias, agglomerates,etc.
Onto the Torr Works super quarry to look at the Carboniferous rocks found there. We had some very good views of the unconformity where Jurassic rocks can be observed to overlie Carboniferous rocks.
Fossils included horn corals, brachiopods and trace fossils left by burrowing animals, we also noted fault features.
The last visit of the day was to Doulting Stone Quarry to examine the Jurassic rocks found there.
The machine pictured above is used to ‘saw’ into the rock. We found more evidence for burrowing animals, there were fossil belemnites too. A discussion of the Doulting rock type established that it did not appear to be made of ooliths but is made up of calcite crystal that are likely to be remnants of Carboniferous crinoid being reworked and incorporated into the later rock formation.
Day 2, 13th October:
The day started with a slideshow presented by Juliet on the ‘Geology of the Mendips’. Peter then organised a closer look at fossils from the Coal Measures.
Field trips to Ubley Warren and Burrington Combe including lunch in the Burrington Inn ensued thereafter.
At Ubley Warren we discussed the evidence for mining that remains how the ores were formed and looked at the fossils seen in the limestone.
After lunch we explored Burrington Combe looking at corals, dolomite exposures and moving up to the lower Limestone Shales in West Twin Brook, at the base of the Old Red Sandstone.
Day 3, 14th October:
The day was spent exploring Carboniferous volcanics and associated rock and structures at Swallow Cliff and Middle Hope on Sand Point, unfortunately you have to go through Weston Super Mare to get here.
The things discussed included raised beach deposits, pillow lava, basaltic tuff, volcanic ash, the relative relationship of these events with the Variscan Orogeny – the volcanic activity pre-dates the mountain building period when uplift occurred.
Fossils found included Michelina, a colonial coral; Spirifer and Rhynconellid brachiopods, etched out of the rock and deep red in colour; solitary corals such as Zaphrentis; and the burrows made by escaping Lingula brachiopods as they became buried by successive layers of volcanic ash.
The weather was glorious for mid-October far better than had been predicted.
There was some interesting archaeology as well including field systems, dry stone walls, and mounds, a lot of this is probably associated with Woodspring Priory, and there were some small sea caves!
Tav headed to the rift to retrieve a skip and rope while Jake and I went on to the dig at the end of 20. There we continued where we left off last week just using the mattock to loosen the fine sediment, silty sand with some interesting colour bands but no large rocks. When Tav arrived with the skip and rope I set about removing boulders along the skip run using the capping gear.
At the end of the session the skip run was clear, just requires a few skips of sediment to smooth it over, and there was a very large hole where Jake and Tav had been active.
30th September-3rd October and 7th-10th October 2016: with Bath and Camerton Archaeological Society (BACAS).
Spent a few days with BACAS carrying out geophysical survey of two sites in Stanton Drew. the first location was at Tithe Barn fields, just off Sandy Lane (image above) where resistivity and magnetometer surveying was done. Before the survey could be carried out there was a lot of moving of electric fences required as the fields were split into paddock areas for horses and ponies. The site itself slopes downwards to the north from Sandy Lane towards the River Chew where a former mill and associated leats is located. The underlying geology on the higher ground comprises bedrock of Mercia Mudstone Group of Triassic Age this if overlain on the lower river valley by superficial deposits of Alluvium – clay, silt, sand and gravel of Quaternary age. Some of the survey results might reflect this changing geology.
The second site of interest was the field opposite the Druids Arms public house (image below). This surprisingly elevated situation had extensive views (if the buildings were removed) of the stone circle sites and Maes Knoll is easily visible. Again carried out resistivity and magnetometer survey although unable to finish all the resi in the time allowed. There was some previous work carried out c.1996 but only an interpretation remains as the raw data has been lost.
A full report of the geophysical will be produced at a later date so I will not provide any interpretation of the results here.
6th October: with Jake. Tav took some members of the Axbridge Caving Group (ACG) on a tour.
Tom Chapman briefly appeared to show where the small mammal bones had been found and led us up to the main entrance. Jake and myself climbed up to the proposed adventure caving route while Tav and the ACG reverted to the more usual route into 20. The area where the bones were found has largely been cleaned and I suggest that they were either deposited by a predator (owl or other raptor?) some of the bones might have been carried in by nesting jackdaws, I have seen similar occurrences in caves in Yorkshire.
Anyway we continued through the show cave and up to the top of 20 where we put Tav’s new mattock quickly to work. We started excavating a trench in the area where the UBSS had shown some scant attention. The digging is mostly of fine sediment, silt and sand. Tav and Pete Flanagan (ACG) made a brief appearance giving Jake the opportunity to clear a skip run for later use.
It will require a few more digging sessions before we have a clearer idea of what lies ahead, although both Jake and I detected a very feint air movement low down at the current end of the dig.
As ever it was very warm, sweaty work and a thirst was coming on, we called it to an end and headed out of the cave to get some refreshment at the Hunter’s Lodge Inn.
On arrival at the Wookey Hole car park we were greeted by Tom Chapman who presented me with a small box of animal bones and a single pot sherd recovered from a site within the cave. The bones, at first glance mainly rodent, will need to be cleaned and sorted and a visit to the site will be carried out soon.
At the top of Chamber 20 capped more rock and a better look at the prospects was possible. After some discussion and scrutiny of the area we decided to dig in the area that UBSS had previously been scratching around. We did some general tidying of the area mostly removing a dump of rocks to a safe place before exiting the cave. We will return to the site next week to continue the dig.
22nd September 2016: with Jake, Tav, Duncan P and Gary Jones.
Slight adjustment to the position of our dig in Chamber 20 away from the fractured rocks. A couple of the more unstable boulders were capped and cleared. With a bit of clearing, mostly cobbles, gravel and finer sediment a promising looking gap could be seen. Capped another boulder to uncover flowstone and an enticing small gap under what appears to be a solid roof. There are some boulders that require some more attention but that is a task for the next session.
15th September 2016: with Jake, Tav, Duncan P and Pete Hall.
While Duncan and Pete headed off to look at ’19’ before joining up with the rest of us later. Jake, Tav and Vince carried on to the dig at the end of ’20’.
A mixed bag of bucketing out sediment interspersed with the occasional capping of a rock obstruction. Downward progress was made but we still need to go deeper.
We might have to consider removing the fractured rock on the right hand wall, there is a lot of it, as we go deeper the fractured rock might be a problem.
All too soon time ran out and it was time to exit the cave and head up to the Hunter’s for the usual debriefing.
More of the same at the end of Chamber 20. Drill hole, place cap and whack, result big boulder reduced to manageable pieces, repeat several times. Shifted a lot of rock and some sediment. Looks better but not deep enough yet. Work will continue next session.
Capping boulders at the top of Chamber 20 new dig site. Some went, some needed more than one hole, some didn’t go at all. We shifted a lot of rock and more requires removing before a proper look can be had.
29th August 2016: With Nick Hawkes, Pete Bolt and Snablet.
L to R: Pete, Nick, Vince and Snablet almost ready to venture underground.
A great trip ably summed up by Nick in his report below:
“The trip was arranged amidst a birthday drinking session, partly as it was long overdue, but also as a one- off opportunity to get Snablet back into Wigmore during his brief visit ‘home’ to Mendip from his new abode in New Zealand. Apologies were received from Pete, Claire, Brockers and Duncan all of whom were unable to join in.
A jovial reunion crew of 4, Vince, Pete Bolt, Pete Mcnab (Snablet) and Myself met at 11am(ish) with Tony coming along to the entrance as official gate master. Vince brought the Hilti capping kit and drill which was shared between us for carrying down. Its inaugural run into HCH/Wigmore to prove its worth!
An uneventful trip straight to the Terminal Boulder Choke was interspersed with occasional grunts of appreciation of the ‘fine’ passages from both Snablet and Pete Bolt.
Once in the choke, debris from the previous ‘snapper’ set by Chris Jewel and myself several moons back was quickly cleared before unleashing the capping tool. Approximately 6 caps were set off over a period of 30 minutes to one hour or so with rocks being passed back gingerly. With each capping the boulders had a tendancy to shake more than felt comfortable so a tick box list of risk assessment was undertaken by those waiting at the back….The overwhelming conclusion being that there was no better way to spend a sunny bank holiday weekend than sitting underground inside a funnel of large loose muddy boulders with a group of old friends, a couple of crowbars, hammers and small explosive devices….this therefore equated to full mitigation of all risks to irrelevant status.
On reaching this conclusion Vince’s head disappeared through boulders in the floor. After a while a message was relayed from the lost head that another opinion was needed as to what to do next. It sounded tight. The way on drops and follows in the stream with a solid roof!….but after ~8m of low wet grovel turned left. A change of water noise levels was noted, as was a fair sized black hole, but a small rock lip prevented progress. After struggling to pass through and temporarily being stuck I extricated myself and tried hammering past. This failed and another Hilti cap was used which successfully opened up the way ahead. Vince’s head disappeared again but was soon heard making loud happy yelping noises …..something about a pitch….we all followed and looked in awe down a large open Pitch with a stream tumbling down and a walking passage heading off to the left below . We quickly realised we could free-climb down and that now there were no loose boulders!
“Crap” was the next cry….the adrenalin rush suddenly dashed as the first of us reached the passage at the bottom. It’s a sump!
Walking into the brown sump to brush away the foam and find an airspace revealed none, but did establish that the sump is deeper than a person over 1.5m wide and ~3m long. A fossil coral was noted in in the stream gravel.
Excitement over, we had had a good trip, and returned to surface and to the QVic. We think this may be the turnaround of the stream to head now towards Cheddar….if it wasn’t for that bloody sump!
Two glimmers of hope remain….a passage high up possibly bypassing the sump or the possibility that it’s just a short duck….
Ready for you Claire…..”
Snablet, Pete and Nick washing kit after a fine caving and exploration trip!
27th August 2016: with Duncan Price, Rick Stanton and Karen Dealy.
Trip to assist Duncan who was going to dive the sump at the end of the dig [not quite] to Wookey 24.
I hadn’t seen the passage beyond the inclined bedding as this had been opened while I was recovering from surgery on elbow. It is very Eastwater like, reminds of the West End but with a liberal coating of mud ending in a deep clear pool of water.
Duncan kitted up while balancing on some precariously wedged boulders and was soon in the water. Rick had come down to the sump while Karen waited at the top of Wookey 20, when DP had gone Rick went back up to join Karen. I waited for DP who wasn’t too long. De-briefed and de-kitted, it was time for us to head out, then you realise how steep the climb back up is and just how slippery, it is not a journey that can be rushed and slow progress was made. Then there is still the climb back up the rift I was glad when I had reached the top of Wookey 20.
There is still more to do in the sump but fresh bottles are required.
L to R: Pete, Nick, Vince and Snablet almost ready to venture underground.