Fossil Hunting on Trimingham Beach
Local Beachcomber and Fossil enthusiast Geoffrey Pardon has been collecting important remnants of our geological past for many years, which he has now decided to share.
Fossil hunting in the summer months is usually not very productive as a good storm is required to shift the beach material to reveal anything. However, if you visit the beach enough times then something always turns up.
These fossils were all found on Trimingham beach this summer. They have not yet been positively identified but I have attempted to suggest what they might be.
↑ A trace fossil of a jellyfish? A very faint imprint on the surface of a flint stone. Flints are formed in a process where silica derived from micro-organisms combines with limestone and chalk to form nodular masses and concretions under huge pressure. This fossil comes from the Trimingham chalk which is about 65 million years old.
↑ MANDIBLE BONE – canine lower jaw bone. The molar and pre-molar teeth are present but the front part of the jaw with canine and incisor teeth is missing. The broad section suggest that it is from a wolf.
Found east of the Vale Road gangway in the stones on the open beach, it dates from the Holocene or Recent after the last ice age around 15 to 20,000 years ago.
↑ FRONTAL BONE – top of the skull from a DEER. The two antler bases can clearly be seen at the top. Found in a hard sandstone / shale bed well down the beach, the rest of the skull has been eroded away. Holocene / Recent, about 15,000 years old.
↑ SCAPULAR – joint end of shoulder blade, possibly from a deer or small horse. This fossil was found amongst loose pebbles halfway down the beach. Holocene / Recent, about 15,000 years old.
In March the “Beast from the East” brought storms coinciding with spring tides, and this scoured the beaches exposing the chalk beds and rocks all along the coast.
The fossils shown here have not yet been positively identified. However, I have attempted to name and age them myself.
↑ HEXACTINELLA SPONGE Found on the chalk at Sidestrand. Quite rare, because the delicate `arms` do not normally survive intact and only the vase-shaped centre is present as a fossil. The Hexactinella sponge gets its name from the six-sided cell structure of the vase wall. They can have six to twelve arms – this one has eight. The Sidestrand chalk is Upper-Maastrichtian in age and this dates the sponge at around 65 million years old.
↑ The exposed chalk at Sidestrand, on a foggy day in April 2018.
↑ Part of the chalk at Sidestrand, viewed from the cliff top.
↑ SYPHONIA SPONGE STEMS Found loose on the chalk at Trimingham just east of the old fishermen’s gangway. The base of the stem would be anchored to the sea bed and the top part was either branched or vase-like, similar to a tulip flower head. The piece on the left is a branch part. Sponge fossils date from as early as the Cambrian age, up to 500 million years old. These fossils were on the Upper-Maastrichtian chalk at Sidestrand and are around 65million years old.
↑ I am not sure about this, but it looks very much like the “pie crust” edge to a fragment of crab shell. Found loose on the Trimingham chalk at the eastern end of the beach.
↑ A piece of fossil bone – not sure what from, but the hollows suggest it may be from a marine mammal such as a seal or walrus.
↑ ANTLER BASE, GIANT DEER This piece has part of the skull at the base and was still attached to the head when the deer died. It was found lying loose amongst the rocks at Trimingham. Holocene to recent, approx. 600,000 years old.
↑ EQUUS or Wild horse Teeth from the upper jaw or maxilla. Holocene or recent, 600,000 years old. Found on Trimingham beach amongst the smaller pebbles.
↑ Big pieces of mammal bone. They are from possibly Bison, Woolly Rhinoceros, Brown Bear or young Elephant. Pleistocene to recent in age, 700,000 years old. Found amongst larger rocks west of the revetment at Trimingham.
↑ Molar tooth from Bovine, wild ox or similar. Found amongst pebbles on the open beach at Trimingham.
↑ Calcaneum, or heel bone from a cleft-hoofed mammal such as deer, buffalo, wild goat or ox. This bone is most likely from a deer and around 600,000 years old. Found on Trimingham beach in rocks to the west of the sea defence.
OFFICIAL IDENTIFICATIONS from Trimingham Beach
The samples which appear below were all collected by Geoffrey from Trimingham beach, and have been officially identified by the paleontology department of Cromer Museum.
Vertebra, thoraxes or back bone segments from giant Bison. Both pieces are incomplete and found at different locations amongst the larger beach pebbles. Known as a sub fossil, they date from late Pleistocene or Holocene age 10 to15,000 years ago, around the last ice age.
< Iron Pyrites – “Fools` Gold”. Not actually a fossil but a metallic mineral which forms nodules and granular masses of cubic crystals in sedimentary rocks. Pyrite is very susceptible to weathering leaving a residue of brownish limonite. Very heavy and dense it is usually found in the lower parts of the beach.
CONULUS – sea urchin on left and MICRASTER – heart urchin on right. Both types lived on the chalk seabed in the late Cretaceous 150 million years ago. Common size about 25 to 30 m/m.
< CENOCERAS – Nautilus. Part fragment of the whorl shell often mistaken for an ammonite. A marine cephalopod that fed on small seabed-dwelling creatures and the head part had well-developed eyes and grasping tentacles. It swam by squirting water out of the body cavity. A single genus survives today living in the southern Pacific. This fossil dates from the middle Jurassic period 160 million years ago.
TYLOCIDARIS – sea urchin. Lived on the chalk sea floor and had large defensive splines around the outside. From the late Cretaceous to Palaeocene period 500,000 years ago. Found amongst the smaller pebbles, they are about 40 m/m in diameter.
< Juvenile Deer, lower right jaw bone. This piece of fossil bone was found in a gravel stream bed which is now under the tarmac at the end of Vale Road next to Marl Point. It dates from the middle Pleistocene, 15,000 years ago. Known as a sub-fossil preserved after the last ice age.
ECHINOID – sea urchin. This fossil has formed in solid flint and the petal bases have been very well preserved. Found in the chalk reef it has been protected from the erosive action of the sea on the beach. It dates from the late Cretaceous period 60 million years ago.
< AUSTRALICERAS – a less common ammonite distinguished by the fine, closely-spaced ribs. It dates from the early Cretaceous period 120 million years ago.
PINNA – a fan mussel, embedded in flint. From the early Jurassic period around 150 to 200 million years ago. A bivalve filter feeder which lived in groups with the pointed anterior end buried in the sediment, this part has become fossilized in this example and in life the shell would have been about 200m/m long.
< BELEMNITES – one of the most common fossils found locally. Usually found scattered amongst the beach pebbles, but can be found embedded in the chalk when it is exposed. The belemnite at the top of this photo is attached to flint and was found on the chalk. Belemnites fossils are the remaining part of cephalopods, which include the living squid and cuttlefish, and they lived in the shallower waters of the Late Cretaceous Chalk sea around 60 to 150 million year ago.
ECHINOCORY, or Sea Urchin. These creatures lived partially buried on the sea bed and with mouth parts on the under side fed on small particles from the sediment. They are often found with the top of the dome missing and this was probably due to the attack of predators. In life they were covered in fine tubercles along the dotted lines clearly seen here. They date from the late Cretaceous period around 60 million year ago. And are found in the upper chalk layers.
< OSTREA, common Oyster. Lived in marine estuarine waters and were filter feeders. They anchored themselves to hard rock surfaces and the young cemented themselves to the older molluscs eventually forming a small reef of shells. They date from the late Cretaceous period 60 million year ago. A common fossil, usually found scattered amongst pebbles and flints on the open beach.
GRYPHAEA, Devils Toenail, a bivalve mollusc that lived on the sea bed anchored to rock a by its tip. Dating from the early Jurassic period around 150 million years ago. Fossils are usually found amongst pebbles and flints on the open beach.
< Juvenile Elephant / mammoth milk teeth. The ones on the left are not in wear. They date from the Lower Middle Pleistocene period, 600,000 to 1 million year ago. These fossils were found amongst the flints and pebbles on the open beach after a scouring storm tide and are likely to have been washed from the sea bed offshore.
Mammoth tooth fragments, broken off from full teeth which would be around 200 to 250 mm in length. They date from the Middle Pleistocene period 600,000 to 1 million years ago.
< Antler fragments. Another common fossil found on the open beach. It is very rare to find larger pieces of antler as they easily break up with the action of erosion and the sea. These fossils date from the Pleistocene period or later 600,000 year ago.
Elephant limb bone fragment. Pleistocene period 600,000 to 1 million years old. Found on the open beach amongst the larger flints. This fragment measures 100 m/m across and 250 m/m long.
< Head of Fema bone, Elephant. From the late Pleistocene period 600,000 years ago. Found on the open beach amongst the larger flints. It measures 150 m/m across.
AMMONITE – one of the oldest fossils to be found locally, they date from the Devonian period 400 million years ago or earlier, and up to the late Cretaceous period when they became extinct, around 100 million years ago. This fossil was found totally encased in grey limestone with only the small area on the right exposed: the stone was broken to reveal the complete fossil inside.
DAY TO DAY FOSSIL COLLECTING
A belemnite discovered on the beach at Trimingham by Liz King. It is part of a squid-like creature which flourished between the Jurassic and Cretaceous ages around 150,000,000 years ago.
Hunt the Belemnite! These seem to be very easy to find on the beach at Trimingham. This is a haul, mixed in with other geological curiosities, which Liz brought back on 9th-10th Feb 2018. Several were discovered all together beside one of the groynes.
For information on what to look for on the beach at Trimingham and continuing on to Sidestrand beach, see the UK Fossils Network web-site:
Sidestrand and Trimingham Cliffs are certified as a Site of Special Scientific Interest (SSSI). The official notification for this, containing the reasons for its classification, appears on this certificate: