By Neil Clark (UK)
To not be confused with the Elgin Marbles, the Elgin Marvels truly come from the Elgin space of Scotland. They’re well-known fossil reptiles and their footprints, of Permo-triassic age, that have been collected from previous sandstone quarries principally over a century in the past. They’re partly what impressed me to take up palaeontology though, at the moment, I had by no means truly been to Elgin, nor ever seen the fossils. It was by way of the lectures of Professor Euan Clarkson of Edinburgh College within the Nineteen Eighties that I first grew to become conscious of those animals. Nonetheless, it was not till a lot later that I got here head to head with the Elgin Marvels themselves.
In the summertime of 1996, whereas recovering from a damaged leg because of dinosaur searching on the Isle of Skye (see my article in Concern 12 of Deposits), I used to be requested to offer a chat on my exploits at an Open College Summer season College in Edinburgh. Many of the speak was involved with the research of dinosaur footprints, their interpretation and identification. After the lecture, I joined the scholars of their standard nocturnal social dialogue teams.
It was right now that I used to be approached by one of many college students who claimed to have seen some historical footprints within the bedded sandstones close to Elgin. The coed, Carol Hopkins, invited me to Elgin to take a look on the footprints she had discovered. I couldn’t move up the chance. As quickly as I used to be ready, I went to Elgin. Carol had undertaken some analysis into the historical past of fossil discoveries in and round Elgin, and was in a position to verify that what she had discovered have been, beforehand unreported. I, in my view, was in a position to verify that they have been certainly footprints.
Carol was impressed to search for extra. She visited her native quarry at Hopeman (Clashach Quarry) and located an unlimited variety of footprints being excavated from the Hopeman Sandstone Formation SSSI (Web site of Particular Scientific Curiosity) quarry at Clashach. Permission was obtained from Scottish Pure Heritage (SNH) as a result of it was a SSSI, and in addition from the quarry house owners, earlier than the go to to Clashach Quarry.
The quarry had lately been reopened to provide stone for the dealing with of the brand new Museum of Scotland in Edinburgh. Sue Warbrick (then Space Officer for SNH in Elgin), who took an lively curiosity within the quarry and the brand new discoveries, usually accompanied Carol on her forays. By 1997, Carol had investigated over 200 footprints and trackways with over 120 tail drags, and that was only the start! The tail drags have been vital as solely 4% of beforehand recognized Permian trackways had them. By 1999, Carol had investigated over 100 trackways with tail drags constituting over 40% of the trackways found.
The animals that have been thought to have made the vast majority of the footprints have been mammal-like reptiles. Lots of the tail drags have been straight, suggesting that the animal didn’t transfer sinuously like a lizard does. The one place close by the place reptilian physique fossils had been discovered prior to now was at Cuttie’s Hillock close to Elgin. The Elgin reptiles included dicynodonts, a pareiasaur, and a doable procolophonid. The Cuttie’s Hillock sandstones could possibly be dated from these fossils as being of Late Permian age, about 250 million years previous. Because the Hopeman Sandstone Formation lacked any particularly identifiable or dateable fossils, it has been inconceivable to say precisely how previous it’s. We all know that it’s overlain unconformably by a Triassic sandstone and that it consists of aeolian dunes attribute of each the Permian and Triassic. Nonetheless, tying the age down extra exactly was inconceivable.
In September 1997, I invited Professor Hartmut Haubold, a world expert on Permo-Triassic footprints, to visit Clashach. He was very excited about the prints and was able to suggest interpretations of some of the more confusing trackways. One in particular was very perplexing. A three-legged creature with a tail drag to one side and the footprints almost at right angles to the trackway direction, turned out to be an animal walking across the face of a steep dune. He stated that the footprints were of immense significance. They would help to interpret a range of footprint types and better understand the different states of preservation, and would also provide a useful reference resource for interpreting animal-environment interactions. All this was very interesting and useful, but I was greedy and wanted something that registered a little higher on the excitement chart.
The month prior to Professor Hartmut’s visit, Bill George, who worked in the quarry at Clashach, had found an intriguing rock with a hole in it. The rock was from the western end of the quarry where the strata were pink in colour. The rock, which had been removed, was too large for a lorry to transport and was split further in the quarry. When it was split, the hole was revealed. Carol and I had asked the quarrymen to look out for holes in rocks, not just the footprints, as these may represent the remains of fossil animals. No fossil bones had ever been found in the Hopeman Sandstone Formation except for a small unidentifiable fragment from Greenbrae Quarry in the 1960s, so this discovery was potentially an extremely important one.
Carol had already measured the extent of the cavity using wire and determined that it went about 25cm into the rock. At that time, there was really only one way to deal with mouldic fossils and cavities of all sorts, and that was to fill the space with rubber and then smash it open with a hammer to remove the rubber. Luckily, I had decided that this was probably not the best way to investigate the cavity. I had previously done some computed tomography (CT) of a set of dinosaur eggs for the BBC’s Tomorrow’s World, and felt that this was a useful technique that could be applied to this situation as well. So, I removed the rock with the hole and took it back to Glasgow to be investigated further – with permission from Drew Bailey of the Moray Stone Cutters, and Susan Bennett of the Elgin Museum (who were ultimately to receive the rock into their collections).
At the Western Infirmary in Glasgow, we performed some preliminary scans of the hole in the rock. It was not easy scanning through such a thickness of rock and the machine had to be tweaked close to its limits – certainly beyond the safe parameters for normal patient safety! I met Dr Calum Adams at this hospital, a consultant radiologist, who became intrigued by the scanning of this strange object. He moved to the Royal Infirmary in Glasgow and finally settled in the Royal Alexandra in Paisley where we continue today to scan fossils during ‘down-time’, or for ‘testing the equipment’. At each location, he allowed me to bring the lump of rock from Clashach for scanning using both CT and Magnetic Resonance Imaging (MRI).
As the CT produced its first scan, I was confused. What we saw was a Mickey Mouse-like image that was difficult to interpret. When all the scans were collected and collated into a 3-D composite, the nature of the hole in the rock became clear. It turned out to be the entire skull of a mammal-like reptile. How lucky was that!? The chances of the first recognisable fossil from the Hopeman Sandstone Formation being the entire skull of a mammal-like reptile, I suspect, were remote. Not only that, the size of the rock fragment in which it was enclosed was not much bigger than the skull itself.
The MRI scanning was also useful, as it showed exactly why the rubber technique may have caused the loss of crucial information. The lower jaw was not attached to the rest of the skull, so did not allow fluid to pass from the skull (which was open to the fractured surface of the rock) during the operation. If rubber had been used, it would not have passed to the lower jaw, which may have been damaged during the extraction process.
As the MRI was providing slightly more detailed images of the skull, a CT directed drill hole was made at the point where the lower jaw was in closest proximity to the edge of the rock. After this, the rock was placed in a plastic box and filled with fluid to make the MRI scanning work. The whole process was so unusual that the BBC were interested in doing another Tomorrow’s World piece on this new technique for analysing fossils in a non-destructive manner. I’m just glad that no clips from the filming have been used in the many out-take programs that seem to be popular these days. Trying to explain the inner workings of an MRI in simple terms caused my tongue to become severely knotted on several occasions.
Anyway, the results of the research were that the skull was identifiable as being very similar to that of a known mammal-like reptile called Dicynodon lacerticeps from the Late Permian of South Africa. As it differed in some details, it could not be synonymised with this animal but can be shown to be the same as that of a species closer to home, Gordonia traquairi. This is known from the Cuttie’s Hillock sandstones to the west of Elgin, along with a number of other species. Arthur Cruickshank, an expert in such animals, showed that the beast of Clashach was, in fact, the same as Gordonia traquairi and that Gordonia is synonymous with Dicynodon. Sorting out taxonomic messes is not always easy, but the upshot of it is that the Clashach fossil skull is of Dicynodon traquairi… for the time being at least! The fossil also helps us to date the rocks as being from the Tartarian of the Upper Permian.
It is all very well relying on MRI and CT scans to identify fossils, but it is nothing like being able to handle something to complete the sensory experience. For a mere £1,000, I was able to convert the scans of the skull into a life-size, solid, 3-D stereolithographic prototype of the fossil. This is now currently on display in the Hunterian Museum at the University of Glasgow. It is a whole new experience being able to handle a cavity in a rock in this way, and helps one to visualise it better.
In March 1998, the quarrying at the site was increased and put a number of critical footprints at risk of being destroyed. Sue organised a meeting to discuss the movement of the in situ prints to a safe area outside the limits of the quarry. As a result, Drew Bailey of the Moray Stone Cutters kindly offered to move the slabs of sandstone containing footprints to a convenient spot forming an amphitheatre, close to the coastal walk just outside of Hopeman, near to Clashach Quarry. SNH, the Hunterian Museum and the National Museums of Scotland, in association with Carol, produced some interpretation panels to be placed with the footprints. This fossil amphitheatre can still be visited on the coastal path.
All this seems like a nice story of how industry, palaeontologists, museums, heritage organisations, hospitals, students and amateurs can all work harmoniously together and produce important and exciting scientific results. However, not all went that well. One day, while walking the beach with Carol and others, we noticed a square hole had been cut out of a slab of in situ sandstone. Someone had gone to a well-known exposure of the Hopeman Sandstone Formation along the shore and taken a rock-saw to a few footprints. They had removed one of the better-presented footprints and left others with cuts around them. Carol knew of these footprints and the local primary school used to take their pupils to examine them. It is unknown why the anonymous person removed the footprint, but he or she obviously had not thought about the potential impact on the local community, and not even asked permission from the landowners.
The National Museums of Scotland undertook to remove what was left of this vandalised trackway to serve as an example of inappropriate collecting by persons unknown. This year sees a set of guidelines for collecting fossils in Scotland published by SNH for public consultation, following recommendations in the Nature Conservation (Scotland) Act of 2004.
The guidelines were drawn up by a large number of interested parties including landowners, land users, commercial collectors, amateur collectors, professional palaeontologists and museum curators. The hope is that people collecting fossils in Scotland will follow the guidelines and collect responsibly. This would avoid situations where fossils are removed from exposures used frequently by schools, groups and individuals in the pursuit of greater geological knowledge and understanding. Have a read of the Scottish Fossil Code and see what you think: http://www.snh.org.uk/fossilcode/. The consultation ended on 7 September 2007. Its purpose is not to discourage fossil collecting but to encourage responsible collecting.
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