Thanks to Dick Langley for this contribution; thanks to Black Country Geological Society for letting us ‘tag along’ and thanks too to Graham Worton, trip leader, for an excellent job.
The day was led by Graham Worton and commenced at the sycamore tree, site of Abraham Darby’s birthplace one of the fathers of the Industrial revolution. Interestingly the sycamore will soon be felled to make way for an excavation of the site to reveal more history of the home of Abraham Darby, his son and grandson dating back to 1678 . A visitor centre will also be completed on the site next year.
A brief explanation was given regarding the industrial and social history of the site where originally coppiced trees were used for the production of pure charcoal used in the iron making process. Alternatively coal was used and became increasingly more important as an alternative when trees were preserved by royal decree of Elizabeth 1st for the sole purpose of boat and ship building. It was the use of limestone found in abundance at wrens nest that enabled coal to be used where limestone removed the impurities found in coal . Approximately 20,000 tonnes of lime stone per year was removed from the site and distributed via the canal network to the developing iron and steel works nation wide.
The original community of the Wrens Nest area had a long tradition of working in the mines and all the work in setting up the national nature reserve for geology has been completed with the inclusion and involvement of the local residents. Interestingly all the work and exhibits provided by the community are kept in pristine condition unblemished with graffiti or any markings. A tribute to the way the site has been created for and by the community with a welcome for all who come from afar.
Our first walk through a 50 meter long cutting carved out seven years ago took us through layers of rock mud an limestone laid down 400 to 425 million years ago. Recent research has shown that some of ash laid down was from a volcano centred at Cheltenham. The 50 metre walk through the cutting gave a wonderful impression of the sea bed from the Silurian period 400 million years ago.
Over 650 fossils have been found with 86 being unique to the area. Best known of course the Dudley bug, a three lobe trilobite. There was evidence of ripple marking from the sea bed from the seas action on the sand. The study of the area has enabled an understanding of great periods of climate change taking place over a 5 million year period.
The walk proceeded up through the reserve via a butterfly meadow and soccer pitches once used for artillery ranges for gunner practice before the first world war and then on to the seven sister’s tunnel complex one of the best preserved examples of lime stone quarrying worldwide. Several caves have been in filled with loose sand and one with with blocks of ganite.
The Scottish Geologist, Robert Murchison from the mid 1830,s researched the area and befriended the quarry men and miners. For information and findings of fossils he could pay them a fine price. As a result Dudley became the world’s best known site for fossils.
The final cave was infilled but also preserved as a living habitat for a dense bat population where 7 of the nation’s 14 species have been found. The cool temperature suitable for bats is preserved with a damn sheltering the site from the warm southerly winds.
The day was well organised and the lecture brilliantly delivered, I would recommend a visit to the site and to the museum for members of your geological society at any time.
Dick Langley