All went in through the ‘adventure caving route’ near the main entrance where I stayed behind to take some photographs, the rest of the team went on up to the dig at the top of 20.
After taking the photographs I then headed into 20 to join up with the others. I was distracted along the way and stopped to take even more photographs.
Then I got sidetracked by a passage that I thought might by-pass the climb, it didn’t, and I was glad to get back out as it was rather too snug in places and I was not convinced it was entirely stable among the rocks.
Eventually arrived at the dig and joined in with the team shifting spoil back and dumping it in various gaps in the floor of the chamber.
All too soon it was time to depart the dig and we made our way out of the cave exiting by the more traditional route along the tunnel.
Driving down the A38 to Burnham on Sea you can’t miss the prominent feature of Brent Knoll sitting atop a Lias inlier (c.139m AOD) standing out from the surrounding levels.
The Iron Age hill fort has produced evidence for Roman occupation to the 4th century. Enclosing an area c.1.6 hectares it has an inner bank with a second major bank just down the hillside. The original entrance was to the east, the west and south has been artificially shaped by terracing possibly during the Medieval period.
The interior has been damaged by extensive quarrying for the Lias limestone lowering the interior by at least 2 metres. The outer defences to the north have been used for military purposes in recent times.
From the top there are extensive views of the Mendip Hills, the Poldens, and across the Severn estuary to Wales and the Somerset Levels. There would also have been views of the now lost River Siger to the south.
Reference: Adkins, L and R. 1992. A Field Guide to Somerset Archaeology. The Dovecote Press Ltd. Wimborne, Dorset.
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.
