| Bridport Sand Formation | |
|---|---|
| Stratigraphic range: | |
 Cliffs of Bridport Sand between Bridport and Burton Bradstock | |
| Type | Geological formation |
| Unit of | Lias Group |
| Sub-units | Down Cliff Clay Member |
| Underlies | Inferior Oolite Group |
| Overlies | Beacon Limestone Formation or Whitby Mudstone Formation |
| Area | Wessex Basin, Worcester Basin |
| Thickness | Approx. 120 m |
| Lithology | |
| Primary | Sand, Silt Sandstone |
| Other | Clay |
| Location | |
| Country | England |
| Type section | |
| Named for | Bridport |
The Bridport Sand Formation is a sandstone geological formation in central and southern England, noted for forming distinctive cliffs on the Jurassic Coast World Heritage Site.[1][2] Bridport Sand is of Toarcian (Early Jurassic) age and is found in the Worcester and Wessex Basins.[3][4]
The sandstone is very-fine grained to fine-grained and contains regular narrow bands that are calcite-cemented and more resistant to weathering, giving it a characteristic banded appearance at outcrop, such as in the cliffs between West Bay and Burton Bradstock in Dorset.[5] It is named for Bridport and has previously been known as the Midford Sand(s), Cotteswold Sands, Yeovil Sands and Upper Lias Sand(s).[3] It forms a locally important aquifer, particularly around Yeovil.[4] It forms one of the reservoir units in the Wytch Farm oilfield in Dorset.[6]
- ^ "Burton Bradstock rock fall, Dorset". British Geological Society. Retrieved 2 August 2024.
- ^ "Where is Broadchurch filmed? Your guide to the stunning filming locations used in series 3". 10 April 2017. Retrieved 2 August 2024.
- ^ a b "Bridport Sand Formation". BGS Lexicon of Named Rock Units. British Geological Survey. Retrieved 3 June 2016.
- ^ a b "Baseline Report Series: 11. The Bridport Sands of Dorset and Somerset" (PDF). British Geological Survey. Retrieved 3 June 2016.
- ^ Kantorowicz J.D.; Bryant I.D. & Dawans J.M. (1987). "Controls on the geometry and distribution of carbonate cements in Jurassic sandstones: Bridport Sands, southern England and Viking Group, Troll Field, Norway". In Marshall J.D. (ed.). Diagenesis of Sedimentary Sequences. Special Publications. Vol. 36. Geological Society. pp. 103–118. ISBN 9780632019397.
- ^ Morris K.A. & Shepperd C.M. (1982). "The role of clay minerals in influencing porosity and permeability characteristics in the Bridport Sands of Wytch Farm, Dorset" (PDF). Clay Minerals. 17 (1): 41–54. Bibcode:1982ClMin..17...41M. doi:10.1180/claymin.1982.017.1.05. S2CID 131256911.