Making the most of what you have: Fossil collecting for the geographically less fortunate
Jason Sherburn, (UK)
Living near the coast is amazing. Or, at least, that’s how I imagine it to be for budding fossil collectors intent on unlocking the mysteries of the ancient world. However, I live about 50 miles from the coast and, while my own area is not topographically dull, for a palaeontologist, it may as well be a barren landscape.
There were once great treasures to be found, as intrepid coal miners carved their way through the ancient Carboniferous strata, uncovering the likes of Lepidodendron and Calamites (fossilised plants) as they worked. With the collapse of the coal industry in Yorkshire, the demise of collectors’ dreams came swiftly, leaving the life of the Carboniferous swamps firmly in the past and deep underground. However, all is not in vain, as I came to find – but patience is required and one needs how to learn to turn a little into a lot.
I grew up in a large village called Conisbrough, on the outskirts of Doncaster in South Yorkshire, England. Famed for its interesting castle and very old church, I had never heard of fossil discoveries anywhere nearby, except when the coal mines were still open, but that was a long time ago. Many of the few exposed rocks are Permian in age, consisting of Magnesian Limestone, and there is also a dolomite quarry in the Warmsworth area. This left little prospect for finding fossils within walking distance.
Undaunted, I began searching through books on the geology of the surrounding area in libraries. Searching through these institutions is, surprisingly perhaps for some, an excellent place to start a fossil hunt, as the right book can tell you exactly where to look. As it happens, I found the right book in the form of Geological Excursions in the Sheffield Region and the Peak District National Park (by Roger Neves and published by W Hartley Seed) and found that it had a section on Conisbrough (misspelled “Conisborough”).
The book was written in the 1960s and it did not surprise me that it states that the rocks are lacking in fossils. However, it did mention one area where fossils from the Permian could be found, accompanied by a map which was so simple and outdated that it was largely useless. Nevertheless, I had a new goal – research, through books and the Internet, can uncover all sorts of hidden localities. In my case, the locality was an old, disused brick clay pit, just a short walk from the house I had lived in for over 20 years (Fig. 1).
My first trip to the clay pit was almost a disappointing one. However, I soldiered on, carefully searching the little exposure, constantly wondering if I had the right place or if I was foolishly lost in some other area of geological time. Patience and persistence are great virtues in fossil collecting, making success so much better. I found myself right up next to the limestone, trying to decipher which rocks were which and searching through loose bits of rock, when I finally found something. In my hand was what looked like a small bivalve, less than two centimetres long and not in spectacular condition.
As it matched the surrounding limestone, I was unsure whether or not I had genuinely found something, as the mind can play tricks. I kept going, eventually finding another one in better condition, confirming that I had indeed found ancient Permian life. That day, I only found these two fossils, but that was enough to keep me satisfied, at least until my next trip – and I also knew that Permian fossils are rare in the UK, so I felt that I had done well.
On subsequent trips, my eyes were more honed, allowing the discovery of more and more fossils. The first bivalves I had found were Liebea squamosa (Fig. 2) and it seems that these are the most common fossil at this location.
I also found my first brachiopod here. This was Dielasma elongatum, examples of which ranged in size from 4mm specimens to larger ones at around one centimetre in length (Fig. 3).
I then began to research what was happening at the time these fossils were living organisms and what they could tell me, if anything, about Conisbrough itself. My research was mostly online, but the most useful resource was the book, Zechstein Reef Fossils and Their Palaeoecology (by N Hollingworth and T Pettigrew, published by Wiley-Blackwell).
From this experience, I learned many things, from valuable lessons in fossil collecting to facts about the Zechstein Sea. Conisbrough was under a large, shallow, landlocked, tropical sea during the Permian, stretching from the northeast of England all the way to Poland. Temperatures were around 23°C, as Doncaster sat closer to the equator, giving rise to conditions which led to parts of the sea drying out every so often.
The Ashfield brick-clay pit contains the remains of an ancient bryozoan reef, with a low diversity of species. The fossils I collected so far have been small in comparison with the images I used to help identify the fossils. This could be suggestive of many dying as juveniles or failing to reach full size, which, in turn, could be due either to a soft substrate that they were attached to and subsequently sank into or overcrowding leading to high death rates.
From starting off thinking that my area yielded no fossils, I now have future possibilities, thanks to the effort and research I did. I naturally plan to collect more fossils in the hope that I can further interpret what life was like in Permian Conisbrough. There are also fossils I am yet to discover that are supposedly at this location – Bakevellia (another bivalve)casts are supposed to be abundant, but I have so far only found them to the north of Doncaster. I have also found possible fossils of the bryozoan, Acanthocladia, and bivalves such as Schizodus, whichare supposed to be at this locale. After I am finally satisfied with my collecting and interpretations, it’s possible that I will donate my collection to Doncaster Museum and Art Gallery, as it may be useful.
This story of patience, persistence, research and a touch of serendipity is intended to inspire. Many people do not live a stone’s throw (or should that be a brachiopod’s throw?) away from fossiliferous rocks, but that does not mean they cannot appreciate what they have. Even if you live on top of a granite pluton, unlocking your local geological history through your own efforts can be exhilarating. My own fossil finds were small and sparse, yet they mean a lot to me, both for sentimental reasons and because my research and efforts prevailed. If you only find a little, turn it into a lot. Open every book, browse every webpage and turn every rock, because you never know what you might happen upon.