Fossil Coast Drinks is pleased to introduce Steve Snowball as a guest blogger who will be sharing his knowledge, experience and expertise in a series of blogs about fossil hunting on the Jurassic Coast of Dorset. Steve is an accomplished author of "A Guide to Fossil Collecting in England & Wales" and co-author of a series of four other highly-acclaimed guides to fossil collecting on the Dorset coast.
The majestic Chalk headland at the eastern end of Ringstead Bay is White Nothe. For lovers of fossils from the Chalk it’s a dream location, as the geology here exposes almost the full succession of Cretaceous-aged rocks that make up the Chalk, as well as rocks from the Upper Greensand Formation.
Access is best by parking at the Ringstead Bay beach café car park, descending to beach level and then walking east. It’s a bit of a trek but assuming you’ve done some prior preparation and have started out on an outgoing tide, the rocks and boulders that litter the foreshore at White Nothe will give you plenty of time for fossil collecting and the potential to find echinoids, ammonites, nautilus, shark teeth and bivalves.
It’s a rough terrain underfoot, once you leave the relative comfort of sand and beach shingle, so it’s probably not suitable for young children or those with walking difficulties. However, once the dark Kimmeridge Clay starts to diminish in the cliff face, this is where the Upper Greensand begins and blocks litter the beach.
When freshly exposed, the Upper Greensand is quite soft but it considerably hardens upon exposure to the atmosphere, so fossils seen in the blocks will require a geological hammer or lump hammer and chisel in order to extract them.
The photo above shows the start of the Lower Greensand and the blocks at beach level. The cliffs here are are designated as a SSSI (Site of Special Scientific Interest) so there is strictly no hammering or digging into the bedrock. Take your time when extracting fossils. Leave plenty of matrix around them, so they are somewhat protected and can be prepared at home, in more ideal conditions!
A ladder, (shown below) which ultimately leads to the Smuggler’s Path up the headland, is a good indicator of being in the best area for Upper Greensand fossils. The exposure is very much buried under the slumped cliffs and landslide. The most common fossils found in the Upper Greensand are echinoids some of which can merely be picked up from between the rocks and boulders.
White Nothe is 160 metres high and the Chalk here comprises both the Grey Chalk Subgroup (which used to be called the Lower Chalk) and the White Chalk Subgroup (formerly the Upper Chalk).
The Basal Beds of the Grey Chalk Subgroup can be found in fallen blocks on the beach and will contain echinoids, especially the species, Holaster subglobus. The blocks may also contain bivalves and ammonites.
As with any fossil collecting trip, luck will play a certain part as to what is available on the day. The most ideal conditions at coastal sites follow rough tides, where fresh rockfalls can reveal more fossils. However, the winter storms and relentless rainfall of the winter of 2023/24 has meant the cliffs along the Jurassic Coast have become increasingly unstable. White Nothe is no exception and whilst several rockfalls have occurred here, you should remain vigilant at all times.
It will be much safer to avoid standing too close to the cliff face. It would also be very prudent to wear a safety helmet at this location. Traversing the rocky shore can be difficult and it’s easy to trip or fall over. A safety helmet is cheap to purchase (less than £10 in many hardware stores) and is a sensible piece of kit to own.
There will be ample material on the beach and from which fossils can be found. As mentioned previously, it’s best to coincide your visit with a falling tide. If the tide has already begun to rise upon your arrival then collecting will be confined to a limited area and time. Give yourself plenty of time for the return journey. It’s all too easy to lose track of the time and tides come in faster at this headland than at Ringstead Bay and will undoubtedly cut you off.
A sharp bolster chisel is a useful tool, as it can create a wide section around an embedded fossil. Remember that during the extraction the fossil is at its most vulnerable; the surrounding rock (matrix) can be unpredictable and crack or shatter when least expected. A well planned extraction reduces the risk of damage. Try to remove the matrix to within 3cm of the specimen and gradually undercut it, using a chisel and geological hammer.
From left to Right - Left: A Schloenbachia sp Ammonite | Middle: A Cenoceras sp Nautilus | Right: Fossilised Sponge in Flint
Nearer to the tip of White Nothe, Chalk echinoids and other fossils can merely be picked up from the beach. Look carefully among the boulders and particularly where they might have been washed by the tides into crevices between the rocks, especially fossils preserved in flint, such as echinoids and sponges.
Fascinating though they be, echinoids aren’t the only fossils found at White Nothe. Vertebrate remains, although not common, do exist although this extremely rare grinding tooth from a Ptychodus shark was found at White Nothe.
From left to Right - Left: A grinding tooth of a Ptychodus shark | Middle: Shark tooth of Scapanorhynchus sp | Right: Echinoids
About Guest Blogger - Steve Snowball
Steve Snowball spent a total of 35 years working in education; initially as a teacher, then as a headteacher and finally as an education advisor in West Sussex. He retired to live on the Jurassic Coast of West Dorset, where he was able to pursue his keen interest in collecting fossils and spending time walking his dogs, enjoying landscape photography, oil painting and gardening. Steve is the author of ‘A Guide to Fossil Collecting in England & Wales’ and co-author of a series of four other highly-acclaimed guides to fossil collecting on the Dorset coast, all published by Siri Scientific Press.
コメント