UKAFH were fortunate to gain access to this remarkable mile-wide working quarry on Saturday 13th October. A small group of us gathered on this unseasonably mild but breezy day for an excursion into the Middle Jurassic. We assembled in the site canteen for a briefing from UKAFH leader Sam Caethoven and the site management, taking time to enjoy the displays of some of the more exceptional finds to have been previously found at the quarry, before heading into the quarry itself.
Ketton Quarry is an enormous site which provides an extensive exposure of the middle Jurassic from rocks of Bathonian age (dating to around 165 million years ago) to Bajocian age (around 175 million years old). The mile-wide quarry has been worked for many decades and is now 115.6 hectares in size. With full access, this huge quarry provides opportunities to collect fossils from many different beds, however we were limited to an area of spoil where operations were not currently ongoing for safety and practical reasons. Despite this, fossils were still abundant.
The geology at Ketton is complex, with a range of Jurassic-aged rocks recorded. Mostly, three formations are visible in the quarries: the lowest is the oolitic Lincolnshire Limestone which was laid down in the middle Jurassic about 160 million years ago. This large, blocky, rock was formed from small grains of calcium carbonate which were deposited under a warm, shallow sub-tropical sea which was subject to reasonably strong currents. Above this is the Rutland Formation – bands of delta and shoreline muds and sands carried by rivers. Each band, with shelly remains at its base and tree roots at the top, was formed when sea-level rise topped the layer below. Many colours can be seen in fresh exposures of this formation. The exposures at the working quarry (Ketton Main Quarry) are the type formation for the Rutland Formation. Above the Rutland Formation is the Blisworth Limestone, laid down under quiet, shallow, warm conditions during a marine transgression. The Blisworth limestone is full of fossil corals and shells.
Ammonites can be found but bivalves, corals, brachiopods, gastropods, echinoids (such as Clypeus ploti), shark teeth and fish remains are more common. In the past, dinosaur footprints have been seen, along with fragments of their bones, but we were not that fortunate on this occasion.
Blocks of limestone are often full of bivalves, brachiopods, or corals but you need a good geological hammer and a chisel to extract them as they can be very solid, although some rocks will have weathered to the point that fossils can be easily picked out. There were also many loose fossils to collect. Throughout our time on site we were able to find many bivalves and echinoids as well as a few brachiopods and gastropods. Special mention goes to James who took the time to carefully search the fine matrial for quasi-microfossils and found numerous echinoid spines, fish teeth and an Acrodus sp. shark tooth.
At the end of our hunt we gathered in the canteen for refreshments and to enjoy seeing each thers’ finds. It’s quite unusual on a UKAFH hunt for us all to finish together and have somewhere to gather for show-and-tell afterwards and it is always a highly enjoyable part of the day. As well as seeing all the finds and learning more about the site, the quarry staff can also see what we have found, both to share in our enjoyment and to ensure that anything rare is reported and recorded.
UKAFH would like to thank Hanson Cement and the staff at Ketton quarry for allowing us to visit and taking care of us throughout the day, including briefing us, showing us the site and allowing us the use of their facilities.
On 19th August UKAFH visited King’s Dyke Nature Reserve at Whittlesey near Peterborough. This highly productive, family-friendly location is always a popular hunt and places quickly filled up so we had a full house of 35 with leaders Aidan Philpott and Sam Caethoven.
The geology of the location consists the Peterborough Member of the Oxford Clay Formation, representing the middle Jurassic period of circa 180 million years ago. The clay is quarried for brick making but a spoil heap is provided in a designated area for fossil hunting and it was to this area we were destined today.
We were fortunate to enjoy warm but overcast weather, making hunting comfortable and dry. We kitted up we headed down to the dedicated fossil-hunting area where Aidan gave the group an introduction to the fossils that can be found. The commonest finds are ammonites (especially Kosmoceras), belemnites (especially Hibolithes) and gryphaea, an oyster often called “Devil’s toenail” because of their curled, scaly appearance. However marine reptiles have also been commonly found in the quarry as well as teeth and bones from fish including the ray-finned Leedsichthys, probably the largest fish ever to have lived. An abundance of bivalves and brachiopods can also be found.
The location has an enormous quantity of fossils available and they are very easy to find, making it equally perfect for beginners who want to take home a treasure or two and for old hands who want to find something special, be it a bone, fish remains or a particularly large, complete or well-preserved specimen. The clay is easy to dig into and split so it is never a question of finding fossils; rather of narrowing down the large volume of finds into “keepers”. Soon we had good finds turning up, including calcite Kosmoceras ammonites, plenty of belemnite sections and an abundance of gryphaea.
Although on this occasion no-one was fortunate enough to find any reptile bone, a Hybodus sp. shark tooth was found by Silas Shaul – the first I’ve personally encountered from this site. Well done Silas! Some sharp-eyed hunters like Billy Currie found small fish scales, bones and vertebrae and Tracey Herod found a beautifully preserved calcite-filled gastropod with its aragonite shell still in place.
As events drew to a close we received many kind remarks from attendees who commented on how they had enjoyed their day and were pleased with their finds. We always love to hear your comments and see pictures of your finds, whether from one of our hunts or your own forays so please do share your news on our website and facebook pages! Also please do sign up to our mailing list or keep an eye out on our website for forthcoming 2019 hunts which will be published soon.
On 29th January UKAFH members were welcomed to London’s outstanding Natural History Museum (NHM). The grand, terracotta-faced Victorian museum houses one of the world’s greatest natural history collections, with outstanding specimens on public display and a programme of world-class special exhibitions. However, our visit was all about what is behind the scenes of this great museum.
Our fortunate group of fossil collectors assembled alongside “Sophie” – the most complete Stegosaurus fossil in the world – to meet our host for the day, Professor Adrian Lister, a specialist in mammals working in the Vertebrates and Anthropology section of the Earth Sciences Department. Following a brief introduction we were led into the museum (“follow the jazz hands!”) and through the door from the public areas to the true heart of the museum.
It would be easy to make the mistake of believing the only purpose of the NHM is to educate the public with its displays, interactive facilities, information boards, exhibits and exhibitions. However the NHM is in fact a vast repository of some 80 million specimens and functions as an incredibly important research facility. There is a great deal more behind the scenes of NHM than meets the eye; certainly there is an extraordinary amount of space hidden away from the public areas – a veritable labyrinth of storage facilities, laboratories and research offices. It would be impossible to see and absorb the true extent of this enormous hidden world in a day but our visit provided a brief glimpse into the real world of the NHM, it’s specimens and the people who study them.
We began in a special reception area laid on for backstage visitors which showcases some of the museum’s prized specimens. The small but exceptional display includes diverse examples of the world’s natural history, including fossils and minerals – a snapshot of time itself, if you will. Adrian provided an outline of the day’s programme and introduced us to colleagues Zerina Johanson and Paul Taylor who would lead our party round specimens showcasing their personal research areas.
The NHM repository has its own stratigraphy of a sort: the dinosaurs and marine reptiles fossils are at the bottom, then working up the floors you travel through laboratories, birds, mammals, fish, bryozoa, molluscs, ammonites and so on. Within those categories the arrangements can vary: mammals are arranged by geographical location; bryozoa by geological time; fishes by species. Aside from the many researchers working within the museum there is an army of volunteers who help identify, label and digitise the multitude of specimens held. The NHM is working on an extraordinary digital database which is publicly accessible and searchable and will provide an exceptional resource to professionals and amateurs alike, no matte their location. The digitisation process also facilitates metadata, empowering the indexing and cross-referencing of specimens to make the whole far greater than the sum of its parts.
Introductions over, we divided into three groups to visit portions of the British mammal, bryozoa and fishes collections. We had the great privilege of seeing some truly exceptional fossils and learning more about their recovery, preparation, conservation and use as specimens for scholars all over the world.
I came away from the mammal collection with a greater understanding of the abundance and relative diversity of “ice-age” mammals, learning about acquisition of collections from private collectors, whether by donation or purchase. I also learned that mammoths possessed 6 sets of teeth during their lifetime, each successively larger as the beast grew, and that when the final set was worn down the animal was no longer able to feed adequately so the teeth determine not only the age of the animal but also its lifespan. Paul Taylor (who also regularly writes in our own Deposits Magazine) began by expressing great disappointment that Sir David Attenborough has never mentioned the sadly overlooked bryozoa; by the end of our fascinating tour of the collection we shared his mildly offended incredulity! Bryozoa are extraordinary colonial creatures which thrive in a multitude of ways, show multiple examples of convergent evolution through the fossil record and, despite being almost entirely obliterated by the P-T extinction event (the coloured dots on the specimen drawers told a tragic tale of this wipeout) managed a resurgence which means they still thrive today. Microscopic photography revealed the mysteries of their feeding, breeding and defences. Finally, visiting the fishes with Zerina we saw examples of extraordinary conservation, with the most fragile of fossils being parted from or exposed within their rocky graves. Such extraction can come at the price of fragility and loss of context (the matrix can be as important as the specimen in understanding the living environment, preservation and age of a fossil). We saw exceptional casts and replicas of precious fossils and extraordinarily detailed 3D imaging of rare fossils, all enabling specimens to be handled, observed and studied across the world without the risk of loss or damage in transit of the original, precious fossil.
Following our visit to the collections we visited the Angela Marmont Centre (AMC) for UK Biodiversity. Many of you may not be aware of this incredible free resource but we urge members to take the time to discover a little more by visiting in person or online! Located on the lower level of the Orange Zone of the museum by the Queen’s Gate entrance, the AMC provides a range of services and resources that benefits experts and amateurs alike. Services are as diverse as pest identification, which assists in detecting and preventing crop pestilence and monitoring the spread of pests around the globe; and CITES certification which identifies and prevents the trafficking of rare and endangered animals and the products of such trade. But more generally, they offer access to a large and diverse range of UK fossils which can be handled and studied and a vast array of UK biodiversity reference collection of such as insects, butterflies and bird eggs which can be examined.
The AMC has regular opening hours* for visitors to view the collections and also to make use of facilities such as the London Natural History Society’s library and also to bring in fossils and specimens for identification. Aside from the in-person identification service they offer an excellent free online identification forum at www.nhm.ac.uk/natureplus/community/identification. Further facilities include bookable resources such as microscopes, photo-stacking equipment, keys and field guides and workshop space suitable for meetings and training sessions. There are also handouts and information leaflets, including specimen labels, which can be taken away. This magnificent resource, which I have personally made use of on a number of occasions, is already benefiting a number of our members post-tour and we hope to welcome some of the AMC staff on future fossil hunts too!
Last but not least, of course we exited through the gift shops! NHM has a vast range of books and resources to purchase. You can even buy our own book, “A Guide to Fossil Collecting in England and Wales” in the British Geological Survey (BGS) shop inside the museum.
The passion and knowledge of our tour hosts was self-evident and we are most grateful to Adrian, Zerina and Paul and to Christina, Ben and Florin at AMC for their time. We also noted that our hosts had taken the time to understand our group and activities and had specifically shown us examples of specimens that we may have found ourselves, or been able to look for, on past and forthcoming UKAFH hunts. This thoughtful attention to detail did not go unnoticed! Thank you for giving up your time for us to create such a special day.
*The AMC’s opening hours are 10-12 and 2-4pm Monday to Friday, and the first Saturday of the month.
UKAFH fossil hunt at Warden Point, Isle of Sheppey, 12th November 2017 – a preview of some of our group’s finds
On Saturday 14th October UKAFH took a group out to the Warren, Folkestone for day one of the Kent weekender. We were blessed with unseasonably warm weather as our group of 30 descended the (pleasantly dry) mud footpath down to the beach to begin our hunt through the Cretaceous period! Once on the beach, UKAFH leader Chris Tait briefed the group on the geology of the location and what we might expect to find.
The rocks at Folkestone represent the Albian stage of the lower Cretaceous, 110-105 mya. Lower Greensand is found at the base of the cliff with Lower and Upper Gault clay resting conformably atop, however the clay slumps over the Lower Greensand and is eroded at sea level to release large volumes of fossils onto the beach in this highly productive locality for fossil hunting. During the time these sediments were laid down the UK was at a more southerly latitude in the area of the modern day Mediterranean and a warm sea teeming with life covered the UK. During this time sea levels were transgressing, with the Lower Greensand being deposited as and continued to erode, to be replaced with fine clay sediments once nearby land was completely submerged.
The Lower Greensand is less fossiliferous as the near-shore environment it represents was less suitable as a habitat but still contains excellent fossils such as ammonites; the Gault Clay, however, is packed with diverse fossils, some with exceptional preservation. Ammonites, belemnites and molluscs are common; nautilus, crabs, crinoids, fish remains, shark teeth and scaphopods can be found, along with rare finds of reptilia. Examples of all of these were found by members of our hunt group!
Phosphatised preservation is typical but quality is variable, with examples often fragmented or in nodules. However many examples are preserved in superb detail in pyrite and those which are newly emerged from the clay can retain some or all of their nacrous shell. Bivalves and molluscs which are newly exposed are often extremely fragile and are rarely collectable unless carefully removed along with the surrounding clay, but ammonites are more durable and make marvellous specimens to add to a collection.
Soon after we reached the beach heading towards Copt Point the finds were already plentiful. Partial regular and heteromorph (partially uncoiled) ammonites and bivalves were quite common and finds increased as people “got their eye in”. Some of the group progressed quite quickly along the beach to inspect the slips of clay for freshly washed out fossils and check out the shingle between the large rocks and boulders on the foreshore. Others remained nearer the start of the beach, working methodically through the shingle by hand, with a trowel, or dry sieving, in search of smaller finds like shark teeth.
Several members of the group found shark teeth, with Isabelle finding the largest example. At the other end of the scale, Sam found a small but scarce Acrodus shark tooth while sieving using a 3mm mesh. Sieving is a good technique to remove sand and search for small fossils which wash out higher up the beach because they are lighter. Sieving and shingle-searching up the beach yielded crabs, solitary corals, urchin spines, shark teeth and vertebrae as well as fish teeth, a turtle bone and the day’s star find, a swordfish tooth!
By the end of the day we had a really great selection of finds amongst the group!
The following day we were greeted with yet another gloriously sunny autumn day, enhanced by the towering white cliffs of Dover above our meeting point as Samphire Hoe Country Park. We had another full house of attendees and headed west along the beach to hunt for fossils amongst the chalk boulders on the foreshore. Aidan Philpott, UKAFH Leader, explained the geology and identified local fossils to look for to the group. The lower chalk (also known as the grey chalk) at Samphire Hoe is from the Cenomanian stage of the Upper Cretaceous so yields fossils aged 100.5 – 93.9 Mya.
Common finds are brachiopods, bivalves and echinoids. Sponges, shark teeth, worm tubes, gastropods and fish can also be found and, rarely, ammonites. As well as beautifully preserved fossils within the chalk, some echinoids and shells and many sponges form flint casts which can be washed out of the chalk and found in the shingle. Attractive pyrite crystals can also be found in the chalk.
Our first find of the lay was an eroded echinoid inside a flint block. UKAFH leader Chris Tait then found a large section of clam. These giant molluscs are mostly found broken into small pieces so this was a really nice find. As the day progressed a good variety of finds were made including echinoids, shark teeth and brachipods.
Samphire Hoe isn’t the easiest location for fossil hunting as you need to scrutinise the loose chalk boulders on the foreshore carefully for signs of fossils and then extract them very carefully with a chisel to ensure they are not damaged. You can also hammer the boulders to break the chalk up in search of fossils so work, tools and care are needed to have a good chance of finding fossils here. Once extracted, however, preservation is usually excellent, with fine details clearly visible.
Cleaning chalk fossils is easy, requiring little more than dry brushing the remaining chalk matrix with a soft brush (a children’s toothbrush is ideal) to remove any chalk remaining on the fossil surface. As chalk is very soft, you can easily remove larger amounts of remaining chalk with a blunt knife or craft knife until you approach the surface of the fossil and switch to brushing.
Finds were pleasing but not abundant, however everyone enjoyed the hunt and the sunshine day.
Chris, Aidan and Sam, your UKAFH leaders, would like to thank all of our members and attendees for joining us on our weekend fossil extravaganza and we look forward to seeing you all soon!
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The 2nd July was a momentous day in UKAFH history being the last hunt that founder Craig Chapman would lead before stepping down from leadership duties and we were very hopeful it would be a good hunt. We weren’t disappointed!
I had only been to King’s Dyke once before on a blisteringly hot day and got quite pink in the sun! So I was relieved that there was some cloud cover and we didn’t have to worry about people getting sunburnt.
The hunt was very well attended with about 30 or so people eager to pick through the clay in search of ancient treasure. I must thank the quarry owners for having refilled the area the day before giving us 2 large areas of fresh clay to pick through. After a brief introduction at the identification board we headed up to the smaller heap just up the hill and the hunt was on!
One of the best features of this locality is that is suitable for all the family and is productive enough that hunters are guaranteed to go home with something, and everyone who wanted one of the plentiful (and beautiful) flat ammonites found at least one. Belemnites are also very common and range in size from a few centimetres to several inches (sorry about mixing metric and imperial!) The largest complete ones are not to be found everywhere and are quite the prize and I was lucky enough to find a couple of beauties. James found the biggest most complete one and was justifiably delighted with it!
After about an hour or so at the secondary heap we headed down into the main larger fossil hunting area where we were hoping to find some of the other things that can be found from this section of the Jurassic. Fish, crocodiles, ichthyosaurs and plesiosaurs are all known from here but are not common and are a major highlight if you are lucky enough to spot them. Between us we found 5 Lepidotes fish scales and even a couple of fish coprolites.
I am deliberately leaving the best till last, and chronologically they were found last, all within the last 30 minutes of our time hunting. It wouldn’t have been a proper UKAFH hunt in the Jurassic without Craig finding a vertebra and he duly obliged with a lovely ichthyosaur vertebra. I chipped in with 20 minutes to go with my most spectacular UK find – a plesiosaur vert which truly made my day. Then just as we were packing up, a random family who weren’t even part of our group arrived and the young man hunting with his Mum and sisters found a “weird belemnite” that we were not at all jealous to identify as a plesiosaur tooth! They were on their first ever fossil hunt so I shamelessly plugged UKAFH as a great group to join!! Maybe we’ll see them again on a hunt another time, who knows.
Either way it was a great day and the feedback was very positive. Thanks again to the quarry owners for the fresh clay to hunt through and I look forward to hunting there again next month with a new group.