Isle of Whithorn Bay
Also within
Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Caledonian Structures of the Southern Uplands | Favourable | — | 2016-01-14 |
Climate exposure
This is about exposure to a nationwide pressure this habitat type carries — not a verdict on this site's own management.
Coastal habitats are exposed to sea-level rise and storm erosion. Where hard sea defences sit behind them, there's nowhere landward to retreat to — a squeeze that keeps compressing the habitat no matter how well it's managed.
Geology & landscape
Geological Period: Silurian
Landscape processes: Coastal
Description
ISLE OF WHITHORN BAY This site lies within the village of Isle of Whithorn, forming the northern shore of the bay. This coastal section provides excellent exposures of the ‘Hawick Rocks’, of probable Silurian age, consisting of alternating impure sandstones (greywackes) and mudstones. The structural features displayed here are of particular interest and demonstrate very clearly some of the characteristic effects of repeated compression during the Caledonian mountain building episode. These structures belong to the first of a series of generations that can be attributed to the Caledonian Orogeny. At this locality six major first generation folds occur; the hinges of these folds vary considerably in their orientation (plunge), through a total range of 120° about the vertical. This unusual feature is an important characteristic of the first generation folds in the ‘Hawick Rocks’ of this area and is best displayed at this locality. Another feature of interest here is the existence of large-scale folds which pre-date the first generation Caledonian structures described above. These probably formed by slumping of the unconsolidated sediments on the sloping sea-bed, perhaps triggered by earthquake shocks. At the northern end of this section thick beds display unusually clear graded bedding with coarse-grained bottoms, displaying flute casts and load structures and well marked tops with cross-laminated silts and cleaved mudstones. This site provides a valuable illustration of some important aspects of the Caledonian structures of the ‘Hawick Rocks’.