Fossil Finder Database 2022

Ammonite

Wafer thin Most ammonites in shale (compressed clay) are completely crushed flat and are preserved as an impression, sometimes with the white outline of the shell itself. That is why it’s not worth hammering into soft clay cliffs such as at Kimmeridge Bay; not only is it dangerous because of the risk of rock falls,…

Bivalve shell

Clues to ancient environments This is a cockle-like shell from the Portland Limestone in Purbeck. Like a modern-day sea shell, both shells or ‘valves’ are sprung open showing that the animal was not transported far before burial. It is the large muscle inside that keeps the shells together, but when that rots, they naturally spring…

Dinosaur

Dinosaurs in Swanage Bay! The photos are different views of a single dinosaur backbone or vertebra, probably from an Iguanadon. There are dinosaur remains in Swanage Bay and their bones are occasionally washed up on the beach, usually after storms. The very open, marrow texture of the bone, where it has been worn by the…

Bivalve shell

Explosion of oysters! This fossil consists of a mass of oysters from the strangely named ‘Cinder Bed’. This rock layer lies within the Purbeck Beds, a complex succession of limestone and clay rocks that formed in lakes and lagoons at the start of the Cretaceous period. The Victorian geologists thought that the Cinder Bed resembled…

Plesiosaur

Here are three views of a plesiosaur vertebra, almost certainly from the Kimmeridge Clay. The neural arch on top of the vertebra (central image) is largely broken off, while the canal in which the spinal chord once ran can clearly be seen in the left-hand image. The holes and pits in the right-hand image (the…

Ammonite

These ammonites are probably Graphoceras. The specimen on the right has the shell removed in places showing the fine growth lines on the shell, and the underlying suture lines where the chambered shell met the inside of the shell itself. Horn Park Quarry near Beaminster is the smallest National Nature Reserve (NNR) in Britain, being just…

Belemnite

Fossil-rich rock In this rock you can see a belemnite, two ammonites, probably Graphoceras, and shell fragments. This shows just how fossil-rich the Inferior Oolite limestone can be. The tiny ooliths that make up the Inferior Oolite are also clear in the rock surrounding the specimen. These formed from grains of sand or shell fragments that…

Bivalve shell

What’s an oolith? This is a quite large and ornamented bivalve shell in which each growth line is beautifully preserved. The tiny ooliths that make up the Inferior Oolite limestone are also clear in the rock surrounding the specimen. These formed from grains of sand or shell fragments that were rolled around in the warm…