| The geology of the area around Chapeltown |
Looking at old Ordnance Survey maps and the LIDAR map, several areas between Kimberworth and Tankersley show a large number of bell pits, which were dug to exploit both the coal and the economically viable ironstone seams that occur in the upper part of the Pennine Lower Coal Measures Formation (PLCMF).
The Claywood Ironstone and the Tankersley Ironstone, which are placed above the Silkstone Coal and Flockton Thin Coal respectively, were the principal horizons worked – as described on p.142 of the geological memoir for the Barnsley district – but the distribution of the bell pits show that some of the intervening ironstones were also worked.
Although I have encountered bell pits at Bray Plantation, which worked the coal and ironstone beneath the Parkgate Rock, and also those that mined the Claywood Ironstone at Kimberworth, I have never seen any exposures of ironstone.
Following my brief exploration of the area around Thorpe Hesley, where my British Listed Buildings Photo Challenge was cut short due to my failure to access or locate the public footpaths during a walk from the A629 to Thorpe Hesley, I wanted to investigate the geological site listed as Hesley Park - one of several sites that I had seen on the Sheffield Area Geology Trust (SAGT) website and had visited during previous walks.
Without giving any details in a very general account of the “Measures between Thorncliffe and Parkgate Coals”, the geological memoir does mention ironstone bands known as the White Mine and Yellow Mine, but SAGT refers only to “Strata above Thorncliffe Coal”.
Using a simplified online Ordnance Survey map, I entered the grid reference of the Hesley Park site and, once I had alighted from the No. 135 bus from Thorpe Hesley, I made my way up through Chapeltown Park to the old railway line that now forms the Blackburn Valley Trail and followed this to the small housing development at Coppice Rise.
I had a walk around the area pinpointed by the grid reference provided, but all I could see were a few outcrops of what I had identified from the geological map as being the unnamed sandstone between the Silkstone Rock and the Parkgate Rock.
This comprises an upper layer of massive sandstone and a cross-bedded flaggy sandstone at a lower level, but there was no sign of the dark grey shales with nodules or the black platy shale with ironstone band, which have been recorded between this sandstone and the Thorncliffe Thin Coal in Fig. 11 on p.37 of the geological memoir
With my Estwing hammer, I obtained 3 specimens form the lower outcrop, with the first of these being very fine grained with a light muddy brown colour. It has a thin layer of ironstone along the joint plane and iron staining extending approximately 1 cm into the body of the rock and contains several fragments of carbonized plant stem fossils.
The second specimen has the same very fine grained texture and light muddy brown colour, but it is obvious thinly bedded and has three bedding planes exposed, with tiny flakes of muscovite mica visible. The third specimen has the same general colour and texture and has noticeable lamination, with it breaking into three pieces when carrying it home in my rucksack and the bedding planes also exhibiting muscovite.






































