Beacon Limestone Formation
| Beacon Limestone Formation | |
|---|---|
| Stratigraphic range: Upper Pliensbachian–Toarcian Spinatum-lowermost Thouarsense ~ | |
Cliff exposure at Thorncombe Beacon | |
| Type | Geological formation |
| Unit of | Lias Group |
| Sub-units | Marlstone Rock, Barrington & Eype Mouth Limestone Members |
| Underlies | Bridport Sand Formation |
| Overlies | Dyrham Formation |
| Thickness | Up to 5 metres (16 ft) Averaging <1.5 metres (4.9 ft) |
| Lithology | |
| Primary | Limestone |
| Location | |
| Coordinates | 50°54′N 2°48′W / 50.9°N 2.8°W |
| Approximate paleocoordinates | 38°24′N 7°24′E / 38.4°N 7.4°E |
| Region | Somerset, Dorset |
| Country | England |
| Extent | Wessex Basin |
| Type section | |
| Named for | Thorncombe Beacon |
| Location | Cliff exposure beneath Thorncombe Beacon |
The Beacon Limestone Formation, historically known as the Junction Bed, is a formation of the early Jurassic age (Pliensbachian–Toarcian). It lies above the Dyrham Formation and below the Bridport Sand Formation. It forms part of the Lias Group. It is found within the Wessex Basin and parts of Somerset, in England. It is well known for the Strawberry Bank Lagerstätte, which contains the 3-dimensionally preserved remains of vertebrates, including marine crocodyliformes, ichthyosaurs and fish, as well as insect compression fossils.